Radar Warning Receivers

© Brooke Clarke 2001 - 2024

Spy Satellites
Modules instead of packaged diodes
Crystal Video -
    Police Traffic Radar Warning Receivers
            Radar Sentry
            Driver Alert
            X & K Band
            Protector Model 8502 (on Ultrasonic web page)
            Radatron Related Patents
            Reverse Engineering
        Valentine 1
        Police Traffic Speed Radar
             Early Radar Patents
        Doppler Modules
            HB 100
            CDM324 24 GHz
            HP 35200A Doppler Radar Module
            General Microwave
            LD2410 24 GHz FMCW
    Aperiodic non tuned wide band receivers
Test Equipment
    What Is It?
APR-25, APR-26
AGM-45 Shrike Missile
AGM-88 High-Speed Anti-Radiation Missile (HARM)
Multi-band Filters
Polar Frequency Discriminators =  Instantaneous Frequency Measuring
W.W. II Glide Bomb
Radar Countermeasures
    M-206 Flare, Aircraft, Countermeasure
    MJU-32A/B Infrared Decoy pyrotechnic Flare
    Brick RR97/AL
    Half Brick P99 770
    M-1, RR-170AL
    Table of Chaff Cartridges
    Chaff, Flare, Launcher Patents
Radar Man
Radar Cross-Section
    Panoramic (Radio Corp or Labs)
    Microscan Receiver
    Cavity Backed Spiral Antennas       
        Vought Aeronautics Antenna Cavity Backed Spiral 218-27510-1 01-54-05080 #CCL362
        AEL Model: ASO111AA Cavity Backed Spiral Antenna
RADAR Guided Missile
LASER Guided Missile
    Line Of Sight Beam Riding
    Russian Anti-Tank Missiles
Laser Target Designator
Laser Warning Receiver

Background and General Information

The Secret History of Silicon Valley (56 minutes) Google Tech Talks, Dec 18 2007 by  Steve Blank is a very interesting overview of Electronic Warfare and how Stanford professor Terman helped develop the west coast infrastructure.  Highly recommended.  The cost in human lives is has a noticable impact on Steve.
Hidden in Plain Sight (1:02:45) at the Computer Museum,   by Steve Blank, Nov 20, 2008  - a very similar talk
The PDF version is as it appeared originally and contains all the illustrations, some of which may be missing or distorted in the html version.
Moon Bounce Elint - PDF - a  CIA paper was SECRET NO FOREIGN,  declassified 2 July 96 - why the Stanford 150 foot dish is one of the best for Moon Bounce ELINT
QUALITY ELINT - PDF - a Feb 1968 CIA paper was SECRET NO FOREIGN,  declassified 2 July 96 - looking at antenna patterns along with actual power levels.
An Elint Vigil, Unmanned - PDF - a  CIA paper was SECRET NO FOREIGN,  declassified 2 July 96 - about the SA-2 SAM system (one of the systems the Limiter Detector was developed) a proposed automatic system (was it deployed?).
Communist Defense Against Aerial Surveillance in Southeast Asia - a  CIA paper was SECRET NO FOREIGN,  declassified 2 July 96 - all illistrations at end of paper
THE OXCART STORY - a  CIA paper was SECRET,  declassified 2 July 96 - about the A-12, aka SR-71
SCIENTIFIC AND TECHNICAL INTELLIGENCE ANALYSIS - a  CIA paper was SECRET,  declassified 2 July 96 - includes mention of SA-2 & SA-6
ELINT a Scientific Intelligence System - PDF - 12 page overview formerly SECRET declassified 22 SEPT 93
The U.S. Hunt for Axis Agent Radios - PDF - Official Use Only declassified 18 SEPT 95 -

The mechanical shutter based APR-25 Radar Warning Receiver was modeled after an early Police Radar Warning Receiver.  So the stories about pilots jury rigging automotive police radar detectors into aircraft may be true.

Carrier based aircraft operating near Vietnam were supposed to turn a manual switch on their Radar Warning Receiver (RWR) to short out the receiver before they left the plane.  They were also not supposed to activate any of their radar's while on deck.  If both of these rules were broken the result would be that the RWR with the switch in the receive position would have it's front end burned out.  The pilot would not know this until he was attacked with no warning from the RWR.  Hence the need for a Limiter-Detector that would be immune from this problem.

The soviet block surface to air weapons were the SA-x missiles and the ZU-23 gun.
When a gun is mounted on a truck it may be called a Technical (Wiki) or Gun Truck (Wiki) if it has some armor or Improvised fighting vehicle (Wiki).

ZU-233 gun

SA-2 Guideline (Wiki: S-75 Dvina)

This was a game changer system that was/is capable of shooting down aircraft flying at over 60,000 feet.  Developed in 1957, shot down a RB-57D (Wiki) over China in 1959 (but they claimed a fighter shot it down).  The first public shoot down was the U-2 of Francis Powers in 1960 (Wiki).

The Spoon Rest early warning radar (Wiki: P-12) operates at VHF.  Note search radars typically operate at low frequencies while tracking/guidance radar's operate at short microwave frequencies.  In 1999 it played a part in shooting down an F-117 (Wiki).  

The Fan Song Fire control & tracking radar (Wiki) operates in what's now called E (2 - 3 GHz), F (3 - 4 GHz)  and G (4 - 6 GHz) bands.

The Radar Warning Receivers and Anti-Radiation Missiles (Wiki), like the Shrike (Wiki, see below) or HARM (see below) were developed to cope with this threat.  This also had a major impact leading to the development of nap-of-the Earth (Wiki) aircraft like the F-111 (Wiki), the A-12 (Wiki) designed from the ground up to have radar stealth (Wiki) capabilities and the start of spy satellites (Wiki: Corona) which were controlled from the Blue Cube (Wiki: Onizuka AF Base) in Sunnyvale, CA.

Spy Satellites

I moved this to the China Lake patents page because the Navy was the father of GPS.


This idea is to use raw diode chips instead of diodes mounted in packages because at microwave frequencies the package parasitics (capacitance and inductance) greatly degrade performance.

At the time I was working at Aertech Microwave and we had just started to make microwave modules.  These were patterned after the HP comb generator and PIN diode switch modules that were cylinders about 1/4" in diameter with glass to metal seals in each end.  The HP design sealed the outer sleeve to the module using a welding process that left the end rough.   To get a good joint HP had a recess that was the mating surface for microwave contact.  This was a difficult thing to mate without adding an extra part and so was more expensive than our way of doing it.

I designed our module so that the mating surface was proud of the rest of the module on each end and used a solder process to seal the module. Rather than use an iron to solder we used a Seven Associates single turn inductive heater with the module held in vertical position so you could see the end under a microscope. A solder preform was placed in the groove designed for this purpose and the heater start button pressed.  In a few seconds the solder sealed the module.  The module would then be leak tested using Helium.  Helium is the smallest molecule available for leak testing, Hydrogen is a diatomic gas and has a module that's almost twice as big as Helium. Helium leaks out of balloons much easier than hydrogen, that's why Mylar helium balloons stay aloft much longer than rubber ones.

R&K 260 Probe StationRucker & Kolls and Micromanulipator were the common analytical probe stations that we used a lot.  These have a level horseshoe ring that moves up and down relative to the chuck.  A stereo zoom microscope and an illuminator would complete the station, plus the probes and test equipment.  The micrometer head sets the down height of the horseshoe.  The black knobs on either side raise or lower the horseshoe.  You can see a double sided socket for a plug-in PCB below the horseshoe and there were (are?) companies that would make up probe cards with the tips where you wanted them so you could use either a plug-in card or individual probes mounted on magnetic mounts, each with it's own positioner.  The knurled knobs in the front are the X-Y stage adjustments.  The black knob at the very front is for stage rotation.

We had a number of different modules in our product line including switches, comb generators, limiters and detectors.  A need came up for a combined limiter detector for a classified military program related to Vietnam.  This was for a Quick Reaction Contract (QRC).  These contracts typically carried a government priority rating of DX-A7 or DX-A2).  This meant that we could get our orders delivered before any civilian got his parts and it also meant that the program was watched very closely.

The common RWR at this time was called a "Crystal Video" microwave receiver because it had no RF amplification ahead of the detector and no mixers or Local Oscillators.  An early patent for a Microwave Filter and Detector filed in 1958 and granted 1960 is US 2954468.   You can see that the "filter" grew into a multi band device.

2954468 Microwave filter and detector, George L
                  Matthaei, Northrop Grumman (TRW), 1960-09-27
2954468 Microwave filter and detector, George L Matthaei, Northrop Grumman (TRW), 1960-09-27, -
This design uses a packaged diode (40), similar to the 1N21 so it can only work over a narrow bandwidth.
PS the back (tunnel) diode detectors made at Aertech have low impedance, unlike the high impedance crystal diodes, and so
naturally work over wide RF and video bandwidths.

This Detector (no limiter) has a meandered ceramic matching section. I made up a special housing to hold our separate limiter and detector (LD) in a long tube.  On one end was the microwave input SMA(m) connector and on the other end was the connector for the detector output.

I took this prototype up to the Applied Technology Inc. building on a hill in the Stanford Industrial Park.  It had a great view of the Palo Alto bay area.  Inside there was a room with walls formed by chain link fencing that went all the way to the ceiling.  The gate was open and there were men inside carrying snub nose 38 revolvers.

We tested the prototype by applying radar level power levels (accounting for the path loss across a carrier deck) then checked to see of the detector was fried.  It passed.

Limiter-Detecton in a single package.  I bent the leads to get the module to stay upside down on the scanner.  The two black dots to the left are the shunt limiter diodes, then a 1/4 wave ceramic transformer with a Schottky diode mounted at the right end, then a ceramic capacitor.  I next designed a way to package a combined LD in a single longer module and add a housing at the back to hold the factory select bias resistor and blocking capacitor, DC bias terminal and Video output terminal and have the mounting holes and RF connector be in the same place as the original detector.  This was a form, fit and function replacement that included both Limiter and Detector functions..

  This is a reject unit without the rear (right end) cover installed.  The back end housing was made from a piece of square Aluminum stock with a single round cavity (easy to make with a milling machine or screw machine). The printed circuit board (PCB) that went into the housing was circular in shape with a diameter that matched a punch that was already in our machine shop.  The PCB could be made up in advance with a range of the common resistor values used for setting the detector bias and once the operators had determined the correct bias the correct box would be mated to the limiter detector.

The square box contains the bias circuit and positions the DC input and video output connectors in the same location with respect to the mounting holes as the original ATI detector.  The back of the box was bored in a milling machine with a single cylindrical hole.  The PCB was punched using a Rotex so it would be circular and fit the milled hole.
Rotex hole punch

The ALR-xx systems that used these LDs covered a very wide frequency range.  This was handled by using a triplexer (or quadraplexer) to split the input frequency band into narrower bands.  The exact frequencies were classified.  We built the LDs in various bands to match the requirements for each system.

Switched Limiter Det
            Prototype Another version was the Switched Limiter Detector where the limiter DC return was brought out on a connector.  That way you could apply a bias to the limiter diodes turning them on as PIN switches.  This allows the detection of a CW signal.  This is a prototype unit.  An earlier version applied the limiter diode bias from the back end of the module, but that did not work because there was cross talk between the diode drive signal and the detector output.

The modules were tuned in a clean room using various test setups.  Early on we used the Systron Donner small sweep oscillator that had a box full of signal generator heads and switched between them to get a wide band sweep.  The setup included either an HP Scalar Network Analyzer (SNA) or shortly later the 8410 Vector Network Analyzer (VNA).  There were some simple things that could be done to determine how to improve the VSWR by the use of the VNA that were not possible with the SNA.

A good VSWR that was obtained by good matching was far superior to a good VSWR that was obtained by loss.  This made our LDs more sensitive and at the same time they had the limiter to protect from carrier zapping.

The Wild Weasel (Wiki) project is documented in a short movie produced by the Association of Old Crows called "First In, Last Out" that chronicles the early days of the Wild Weasel program.

Crystal Video & Aperiodic receivers

A big advantage of the crystal video receiver is it's simplicity (no local oscillator, no mixer, no IF amp) which also means lower cost than a hetrodyne type receiver.  The down side is that it is not as sensitive.  But for some applications sensitivity is not the key parameter.

All the devices in this paragraph are functionally crystal video receivers, that's to say they are Crystal Radios (Wiki).  Also see my Crystal Radio web page.

A Crystal Video receiver consists of an antenna, detector and video output.  It covers a wide input band and there's no tuning required.  The crystal video detectors on this page were built for specific (often classified) microwave frequency bands (that corresponded with various Surface to Air Missiles or guns).  These typically include a multiband filter (tri-plexer, Quadra-plexer) with a detector optimized for each filter output (see the AM-6536/ALR-54 for an example).

TechLib - Area 50 - The Bug Duster - has two modes: Normal where the antenna feeds a diode so only works for modulated signals, Pseudo-Sinitsa mode that can detect CW carriers.  The 1N5711 is a guard ring Schottky diode and so has much more capacitance than a similar diode without the guard ring.   Changing to a lower capacitance diode should allow operation at higher frequencies.
Crypto Museum - Sinitsa Синица Body-worn intercept receiver - 30 MHz to 1 GHz.  There appears to be a way to detect that one of these receivers is nearby based on the block diagram. (or maybe by sending a CW signal and looking for harmonics?)

3939476 Passive ranging tail warning device, George W. Leopard, Kirby Hair, App: 1959-05-19, Top Secret, Pub: 1976-02-17, - "There are at present three systems in use for warning a pilot of other aircraft in vicinity. They are passive, transponder, and tail warning.
The passive system consists of a receiver which detects signals from the radar transmitter in another aircraft and causes an alarm to be actuated. (i.e. RWR)
The transponder system requires a cooperating transponder to be located in the unknown aircraft which is interrogated by the pilot in the aircraft being protected.
The radar tail warning system employs radar echoes and indicates position and range of other aircraft located in a cone off the tail of the protected aircraft."
- patented system uses delta time between direct pulse from other aircraft and ground reflection (along with known altitude of self) to determine range to other aircraft.

Police Traffic Radar Warning Receivers

The unit I used when driving the 427 Cobra was the Valentine 1 Radar Detector.  The V1 was designed by a member of the Association of Old Crows.  A very sophisticated unit compared to the first generation detectors shown below.

The military Radar Warning Receiver components I worked on were for detecting pulse modulated RADAR signals so the input had modulation.  A closely related crystal video receiver was the Fuzz Buster (Wiki) for detecting the CW signal from a police speed RADAR.  It used a couple of W.W.II surplus microwave diodes (1N23?) in a waveguide (Wiki).  One end of the waveguide was the horn antenna.  Just behind the antenna the first diode was modulated by a square wave signal at an audio frequency (1 kHz?).  The audio frequency will not propagate in the wave guide so the second detector diode only responded to the change in strength of the RADAR signal.  A narrow band audio amplifier followed the detector diode.  Note a high Q narrow band audio amplifier followed by a meter is the HP 415 meter.  Although made for VSWR (Wiki) measurements, it's also great for doing lab work on something like a Fuzz Buster.  This is because the narrower the bandwidth the weaker a signal can be detected.

An improvement on using a square wave, like in the Fuz Buster would be to use a pseudorandom (Wiki: PR) on/off modulation and a correlation detector.  This is also called a Lock-In Amplifier (Wiki).  I worked with an engineer from England who used this technique to measure the step response of a steam powered electrical generating plant.  It would be impossible to make a direct measurement since changing the input steam pressure from zero to full blast all at once would destroy the turbine.  So he used a piston on the input steam line to make a very small change to the input pressure.  The piston was modulated with a very long pseudorandom code and a correlator sensed the output.  Analog Devices makes Synchronous Detectors for doing this and AFAICR some of these also have a PR source.  I did not see the part I remembered, maybe it was the ADA2200 or AD630 ?  These can see signals 100dB below the noise level.

The common Boy Scout crystal radio is very similar and uses a tuned tank circuit to select the desired station.

I have a Wi-Fi detector that is a crystal video receiver with an LED bar graph display.  It consists of a patch antenna, a bandpass filter, an RF amplifier and a detector followed by an analog circuit driving a LED bargraph display.

Tunnel (really back diodes) make excellent microwave crystal video detectors because the diode impedance is near 50 Ohms so not only provides very good input microwave frequency matching but also provides a very wide bandwidth output signal source from near 50 Ohms so great for seeing the true shape of narrow pulses.  The common crystal microwave detector that harks back to the 1N23 point contact diode (Wiki) has a high output impedance and so is not good for wide bandwidth signals, like RADAR pulses.

Also see my Bushnell Velocity RADAR Gun.


Radatron was the pioneer company making police radar warning receivers.  They were rather crude, but worked and were the basis of the military RWRs that this page is about.  This may be the first police radar detector.

All the current Radar Sentry and Driver Alert units on eBay look identical to me.  They have a single wire to clip the unit onto a sun visor and are powered by a couple of AA size Mercury batteries.

The first units were called Radar Sentry and Driver Alert (what's the difference?  Let me know).

 Radar Sentry

This photo I received of a Radar Sentry from Pat L.,kc2rnn. shows a sheet metal sun visor clip.  Maybe that's a newer version?

Fig 1 Radar Sentry, with Sheet metal sun visor clip.
Radatron Radar Sentry sheetmetal visor clip
Fig 2 back of different unit
Note wire sun visor clip, 1N2x series W.W.II vintage diodes.
Note dielectric rod antenna socket at 45 degrees.
Radatron Radar Sentry sheetmetal visor clip
Fig 3 Inside of battery cover shows:
* Mallory ZM9 Mercury AA size batteries,
* Removable Dielectric Rod antenna.
Radatron Radar Sentry sheetmetal visor clip
Fig 4 the sheet metal sun visor clip looks like it does not belong.
Radatron Radar Sentry sheetmetal visor clip
Fig 5 Behind the bump in the rear plastic cover there are
a couple of 1N2x diodes on a slot antenna for S-Band.
To the right is the working end of the dielectric rod antenna for X-Band.
Note dielectric rod antenna socket at 0 degrees.
Radatron Radar Sentry sheetmetal visor clip

 My Radar Sentry

Fig 10
Radatron Radar Sentry sheetmetal visor clip
Fig 11 Battery compartment on bottom
Blister for S-band, Dielectric Rod for X-band.
Radatron Radar Sentry sheetmetal visor clip
Fig 12
Radatron Radar Sentry sheetmetal visor clip
Fig 13
Radatron Radar Sentry sheetmetal visor clip
Fig 14
Radatron Radar Sentry sheetmetal visor clip
Fig 15
Radatron Radar Sentry sheetmetal visor clip

Driver Alert

X & K Band

This is a newer unit that covers a higher frequency band (Ku) than the Radar Sentry or Driver Alert which cover S and X band.
I'm guessing the yellow light/button lights up when a radar is detected and stays lit until it's pressed to silence the alarm.
The red LED is probably a power is connected pilot lamp.  It would be a bad thing if the cigarette lighter plug came loose and you didn't notice.
Unlike FuzzBuster, the X K model has a plastic cover on the horn antenna.
Fig 1
Radatron X K
                      Police Radar Warning Receiver
Fig 2
Radatron X K
                      Police Radar Warning Receiver
Fig 3
Radatron X K
                      Police Radar Warning Receiver
Fig 4 To open:
Remove 4 each 1/4 hex head screws from rear panel
Remove knob, washer, nut from front panel
Radatron X K
                      Police Radar Warning Receiver
Fig 5
Radatron X K
                      Police Radar Warning Receiver
Fig 6
 2 each cartridge diodes mounted so that their penetration
into the waveguide and be adjusted (Tweaked).
Radatron X K
                      Police Radar Warning Receiver
Fig 7 Projects Unlimited X10W12 module has wires:

Radatron X K
                      Police Radar Warning Receiver

Radatron & related Patents

                      Detector for modulated and unmodulated signals,
                      Hubert H Patterson, George H Webber, AEC,

2901613 Detector for modulated and unmodulated signals, Hubert H Patterson, George H Webber, AEC, 1959-08-25, 329/370; 327/50; 455/337; 455/280 - for 200 to 10,000 MHz. "...three separate components: a broadband antenna, a crystal detector mount, and a high-gain amplifier with provision for either a speaker or earphones."

This is the heart of a crystal video receiver.  Why did the AEC want one in 1957? Let me know.
This patent calls a number of prior art patents for receivers for CW and/or pulse signals, but not microwave.

                      Microwave signal checker for continuous wave
                      radiations, Vernon H Siegel, Radatron R&D
                      Corp, App: 1962-08-03
                      Microwave signal checker for continuous wave
                      radiations, Vernon H Siegel, Radatron R&D
                      Corp, App: 1962-08-03
3094663 Microwave signal checker for continuous wave radiations, Vernon H Siegel, Radatron R&D Corp, App: 1962-08-03, Pub: 1963-06-18, 455/324; 330/10; 342/20; 343/767; 455/130; 455/226.1; 455/325; 455/347; 375/338 - Includes removable dielectric rod antenna, see US7889149.

Fig 1 & 2: Note two W.W.II type diodes mounted on rear wall. Much lower cost than the machined part needed for 2901613 above, but using the idea from it.

Fig 13 & 14 removable dielectric rod antenna.

The Radar Sentry uses two of the Mallory ZM9, Ray-O-Vac M 15 1.35 V Mercury batteries.

2648002 Dielectric antenna, James E Eaton, Navy, 1953-08-04
                      Microwave signal checker for continuous wave
                      radiations, Vernon H Siegel, Radatron R&D
                      Corp, App: 1962-08-03 3094663
                      Microwave signal checker for continuous wave
                      radiations, Vernon H Siegel, Radatron R&D
                      Corp, App: 1962-08-03 3094663
                      Microwave signal checker for continuous wave
                      radiations, Vernon H Siegel, Radatron R&D
                      Corp, App: 1962-08-03
                      Counter-detection system, Vernon H Siegel,
                      Radatron R&D Corp, 1966-06-21

3257659 Counter-detection system, Vernon H Siegel, Radatron R&D Corp, 1966-06-21, 342/20; 342/13 -

Fig 1: a Radar Detector.

Fig 2: Radar Detector at left returns a signal to the police radar (at right) that contains the modulation of the RWR chopper so the police radar can detect that it's being detected.

D194976 Housing for an electro-magnetic wave detector or similar device, William L. Waytena, Radatron R&D Corp,
The design patents does not show a sun visor clip, but otherwise looks like the
Radar Sentry or Driver Alert.

                      Electrical tachometer with saturable core
                      transformer having multi-section windings, Clement
                      R Arrison, Radatron R&D Corp, 1967-07-04

3329892 Electrical tachometer with saturable core transformer having multi-section windings, Clement R ArrisonRadatron R&D Corp, 1967-07-04, 324/169; 324/76.73 -

March 1962 Popular Science ad
March 1962 Popular Science ad

The March '62 ad mentions 1000 hour Mercury battery.
Dual Band means S and X.  But what signal in S-band was there?


When connected to 13.6 VDC nothing happens until the sensitivity knob is turned CW and at some point the light and a tone are heard.  So maybe this is a working unit?

There are two diodes in the waveguide casting.  The diode near the horn antenna (Wiki) is modulated with a square wave and that introduces AM modulation on the CW Doppler Radar (Wiki) signal.  Note that 10.525 GHz is not one of the ISM Bands (Wiki) but rather is allocated for radar use (Frequency Assignments SHF).

The second diode acts as a conventional crystal detector to recover the AM modulation.  There are two fundamentally different ways to demodulate this signal.  The crude way would be to just amplify the detector AC output and use a threshold detector or slightly better add an audio band pass filter.  But a far better way would be to use Lock-in amplifier (Wiki) technology which may have been too complex

Dale Smith is credited as the inventor of the FuzzBuster.  Note it's a huge improvement on the Radatron units in that it has a decent antenna.  Meaning the detection range for the FuzzBuster is much better than the first generation Radatron and probably the second generation Radatron since most people will lose the dielectric rod antenna since it's easy to remove.

FuzzBuster pioneered the use of a Full Wave Bridge Rectifier in series with the DC power cable.  This way the installer does not need to be concerned with the DC polarity thus eliminating problems with prior art detectors if the power supply polarity was reversed probably burning out the receiver.


Fig 1
Fig 2
Fig 3 The Allen screws lock down the diode position.  They
are adjusted by moving up/down using the rods.
Fig 4 The 4 diodes in the lower right corner make the input polarity
a non issue.  For example if a trucker cuts off the Cig plug he can
connect either wire to + or -.  This may be the first use of a bridge
on a DC input device?
Fig 5 14-pin DIP IC marked:
What is it? Let me know
I've been told it's equivalent to the NTE912

Reverse Engineering


The NTE912 "The NTE912 consists of five general–purpose silicon NPN transistors on a common monolithic substrate in a 14–Lead DIP type package. Two of the transistors are internally connected to form a differentially–connected pair. The transistors of the NTE912 are well suited to a wide variety of applications in low power systems in the DC through VHF range. They may be used as discrete transistors in conventional circuits. However, in addition, they provide the very significant inherent integrated circuit advantages of close electrical and thermal matching."
Pinout table, Notch at top center of table.  Another name for this IC may be CA3086.
It's use is described in App Note 5296, even though the app note is for the CA3018.

Q1 C
Q5 C
Q1 B
Q5 E
Q1/Q2 E
Q5 B
Q2 B
Q4 C
Q2 C
Q4 E
Q3 B
Q4 B
Q3 E
Q3 C
NTE912 pinout

Microwave Diodes

Note the Radatron (see above) uses 1N21 type cartridge diodes but the FuzzBuster is using a much smaller diode.  The brass rods that trap the diodes are 0.0875" dia.  The smaller diodes will have smaller parasitics and will work better at higher frequencies.

The diode near the horn is the modulator and the other the detector.
Diode mode (1.0 mA test current, Fluke 87V DMM)

Black to casting
0.565 V
0.431 V
Red to casting
1.966 V

This implies two different diode types are used.  Maybe a PIN and some type of Detector?
When the FuzzBuster is powered up the AC voltage on the modulator diode is 1.13 VAC and the frequency is about 800 Hz (Fluke 87V DMM).

Valentine 1

This is probably the most sophisticated police radar detector on the market.  See my Cars web page for more.  Mike Valentine makes the Valentine 1 radar detector (factory, my cars page).  Rather than use the old fashioned crystal video detection method he uses a hetrodyne type receiver (Wiki) and processes the Intermediate Frequency (Wiki) in a way similar to a spectrum analyzer.  That's to say the receiver can recognize multiple simultaneous signals and so warn the driver of a number of parameters: is the radar gun in front, at the side or behind you (based on multiple antennas), what frequency band is the radar (based on the design of the LO and IF frequencies), and how many radars (based on counting the peaks in the spectrum analyzer display).   This is the ultimate in police radar detectors.


Labeled the "Super Fox", rear label "Super Hetrodyne Radar Receiver".

Fig 1
                        FoxPolice Radar Detector
Fig 2
                        FoxPolice Radar Detector
Fig 3
                        FoxPolice Radar Detector
Fig 4
                        FoxPolice Radar Detector

Patents assigned to FOX Technology Inc.

D249777 Radar
                      detector, Donald L. Roettele, William E. Yohpe,
                      Fox Electronics,1978-10-03
D249777 Radar detector, Donald L. Roettele, William E. Yohpe, Fox Electronics,1978-10-03, -
A single band receiver, hence only one dielectric rod antenna.
D255336 Radar
                      detector, Donald L. Roettele, William E. Yohpe,
                      Fox Electronics, 1980-06-10
D255336 Radar detector, Donald L. Roettele, William E. Yohpe, Fox Electronics, 1980-06-10, -
Dual band requires two dielectric rod antennas - they look easy to break off.
4280223 Radar
                      detector, Donald L. Roettele, William E. Yohpe,
                      Fox Electronics, 1981-07-21
4280223 Radar detector, Donald L. Roettele, William E. Yohpe, Fox Electronics, 1981-07-21, -

This is the same method of detection as the Fuzz Buster, i.e. a diode modulates the incoming CW signal and another diode detects the now modulated signal.
4318103 Compact
                      radar detector and range extender, Donald L.
                      Roettele, William E. Yohpe, Fox Electronics,
4318103 Compact radar detector and range extender, Donald L. Roettele, William E. Yohpe, Fox Electronics, 1982-03-02, -
"A plano-convex dielectric lens extends across the aperture and cavity and introduces a microwave phase delay decreasing from the center of the cavity towards the tapered wall portion of the horn antenna to compensate for the deficiencies in the compromised design of the antenna and for significantly increasing the sensitivity and gain of the detector."

This has the look and feel of a Fuzzbuster (shown as Fig 1, marketed by Electrollert Corporation) except it has an improved antenna.

4733100 Automatic on/off circuit with time delay, Abdul K. Nusairat, Kurt L. Farmer, Fox Electronics, 1988-03-22, - follows ignition with time delays.

Police Traffic Speed Radar

The first popular police speed CW Doppler (Wiki) radars operated at 10.525 GHz.  This frequency is used for Doppler motion detection modules like for door openers.  The Fuzzbuster was a crystal video receiver that consisted of a horn antenna followed by a wave-guide with a couple of W.W.II detector diodes.  The first diode was driven with a square wave that added modulation to the incoming signal and the second diode detected the modulated signal.  An AC coupled amplifier made the detected signal large enough to trip an alarm.

Even though these first generation police RWRs were not very sensitive they worked because of the RADAR range equation (Wiki), that's to say the power level at the RWR is inversely dependent on the range squared but the power available to the receiver in the radar gun is inversely dependent on the range to the fourth power, so the RWR is working with a much stronger signal that the radar gun.

Early Radar Patents

Also see Electronic Altimeters, Radio Direction Finding, Range Finders, Radiosonde: James A. Van Allen Proximity Fuze & Cosmic Ray Patents,

2415095 Radio
                        measurement of distances and velocities, Russell
                        H Varian, William W Hansen, Stanford, App:
                        1938-01-17, (W.W. II: SECRET), Pub: 1947-02-04

2415095 Radio measurement of distances and velocities, Russell H Varian, William W Hansen, Stanford, App: 1938-01-17, (W.W. II: SECRET), Pub: 1947-02-04, 342/109; 342/137 - Which RADAR is this?  Let me know.
used the Klystron tube (Wiki) "invented in 1937 the the Varian Brothers.
2242249 Electrical converter,
                                  Sigurd F Varian, William W Hansen,
                                  Stanford, App:1938-06-18

2242249 Electrical converter, Sigurd F Varian, William W Hansen, Stanford, App:1938-06-18, Pub: 1941-05-20, 315/5.44; 315/5.24; 315/30; 315/39; 331/81; 313/147; 315/5.46; 331/79; 333/231 -

1 GHz operation Klystron
2242275 Electrical translating
                                  system and method, Russell H Varian,
                                  Stanford, 1941-05-20

2242275 Electrical translating system and method, Russell H Varian, Stanford, 1941-05-20, 315/5.31; 313/148; 313/297; 313/337; 313/348; 315/5.48; 330/45; 331/79; 331/83; 333/230 -

The following patents are cited as prior art by Police Doppler Radar speed measuring patents.

2422064 Ground speed indicator (Drift Indicator) , Earl I Anderson, Barco Allen, RCA, 1947-6-10, - Aircraft
2477567 Means for detecting presence and movement of bodies, Eastern Ind Inc, Oct 7, 1944, Aug 2, 1949, - 342/69, 246/30, 342/109, 340/936, 342/114, 340/935, 246/182.00A, 340/552, 342/128, 340/933
2479568 Doppler radar system, William W Hansen, Sperry Corp, App: 1943-08-19, Pub: 1949-08-23, - UHF, involves Doppler processing
2540076 Radio cycle summation measuring apparatus, Oscar H Dicke, App: 1944-09-28, Pub: 1951-02-06, - for surveying distance as accurate as frequency accuracy. motor drives chain of decimal pointers to null Doppler.  also see radio altimeters
2535274 Moving target indicator, Robert H Dicke (Wiki, Pendulums), Sec of War, App: 1945-04-24, - "Doppler effect"

                        Ultrahigh-frequency antenna apparatus, William W
                        Hansen (Wiki), Sperry Corp, 1952-07-08
2602895 Ultrahigh-frequency antenna apparatus, William W Hansen (Wiki), Sperry Corp, 1952-07-08, -
Directly related patents:
2435615 Object detecting and locating system, Russell H Varian, William W Hansen, John R Woodyard, Stanford, App: 1941-09-30
2500178 Ultra high frequency antenna structure
2468751 Object detecting and locating system

This appears to be separate antennas for height finding (left) and azimuth (right).  See: 2415095 above.

Naval gun director radar? (Wiki), Mk 37?

2629865 Radio echo apparatus for detecting and measuring the speed of moving objects, Barker John L, Eastern Ind Inc, Jun 13, 1946, Feb 24, 1953, 342/104, 342/165, 246/182.00A, 340/936, 324/76.39, 246/30
2859435 Speed measuring system, Jr John H Auer, Hugh C Kendall, General Railway Signal, 1958-11-04 - measures the speed of a train.
2927319 Short range radar system, William E Bradley, Philco, App: 1957-01-16, - possible because of the new capability of generating 20 uS pulses.
3024443 Traffic speed monitor, Barker John L, Midlock Bernard J, Lab For Electronics Inc, Dec 2, 1958, Mar 6, 1962, 340/936, 340/441, 235/132.00E, 327/77, 235/99.00A, 324/161, 377/9
3118139 Speed measuring apparatus - on car, i.e. a Doppler speedometer
3187329 Apparatus for vehicular speed measurements, Bernard J Midlock, Laboratory For Electronics, App: 1960-09-30 - mounted in what looks like a boat light, waveguide, transistors, 12 VDC power,
3241138 Radar speed meter, Ernest A Zadig, App: 1964-01-28, - to measure the speed of a car.
3703722 Motion detection system with split-ring monostatic doppler detection, David N Gershberg, Alex Y Lee, E Systems, 1972-11-21, - similar to the Rat Race Coupler (Wiki) Where did they use this?  Let me know.
also see Intrusion Alarm Patents - ME-400 -
3990081 Doppler radar device, Serge Guennou, US Philips Corp, 1976-01-20, - locating a Schottky diode in waveguide so that the power to the diode is optimum for Doppler mixing. - Doppler-Fizean effect: Hippolyte Fizeau (Wiki) was involved in the discovery of the Doppler effect.
4157550 Microwave detecting device with microstrip feed line, Martin J. Reid, Robert W. Terry, Alpha Ind, 1979-06-05 - a waveguide detector that works at both 10.525 & 24.124 GHz.
4581769 Radar warning receiver, Richard L. Grimsley, Michael D. Valentine (Cincinnati Microwave, Inc.), Apr 8, 1986 455/226.1, 340/902, 324/76.27, 342/20
5146226 Motor vehicle police radar detector for detecting multiple radar sources, Clarence R. Groth, Stephen R. Scholl, Michael D. Valentine (Valentine Research, Inc.), Sep 8, 1992, 342/20 -


3438031 Doppler radar having digital speed indicator,
RE29401 Method and apparatus for digitally measuring speed
3689921 Method and apparatus for digitally determining the speed of a moving object
3936824 Method and apparatus for digitally measuring speed


4052722 Traffic radar and apparatus therefor

M.P.H. Ind

4214243 Harmonic detector for traffic radar, - inhibit for moving radar (i.e. in moving police car).

Doppler Modules

At Aertech I worked on a proposal that included testing a Hittite GaAs IC that was a complete FMCW Doppler radar.  AFAICR it was for use in artillery shells and allowed setting the fuze for the distance above ground.  Nothing came of the proposal.

See Ref 35, Ref 36 & Ref 37 or a review of some Doppler modules.

I seem to remember a number of companies working on Doppler Modules since there were many high volume applications.  Automatic door openers was the highest volume, but alarm systems, vehicle crash avoidance systems were popular until the lawyers nixed that idea.  Aertech was going to make some hardware for a microwave aircraft collision avoidance system, but no bid because of the liability being so high.

The ME-400 I labeled as an Indoor Doppler Intrusion Sensor, but I'm rethinking that.  In order to get a Doppler signal there needs to be a mixing of the Tx and Rx signals that will produce a usable output level.  I doubt a single active device can do that.  For example the HP 35200A has a very poor mixer, but did get enough signal so sort of work.

The GSQ-160 Detecting-Transmitting Set, Electromagnetic - Senses a change in the antenna impedance.

RE25100 Object Detectors, R.S. Chapin, 1961-12-19, 367/93; 342/28; 192/142R - UHF or acoustic
2826753 Object detectors, Reynold S Chapin, 1958-03-11, 367/93; 342/28; 342/114; 367/94; 367/909; 49/25 - cited by 46 patents,  now: RE25100
In RCA patent 2333688 Distance measuring system - the plate current of a tube driving/driven by and antenna is a function of distance.

Note some modules have IF outputs and others have an On/Off type output, like a PIR (Wiki) outdoor light switch.

Antenna Test Lab - Low Cost Microwave Radar Modules For 3, 10, and 24 GHz -
Microwave Solutions, UK - offers a number of modules

These are different than the proximity fuzes developed during W.W.II.  See: China Lake patents.

HB 100

This may be the most common Doppler module.

Frequency: 10.525 GHz
Input: 5V <= 40 mA
Range: >20 meters (65')
Note the "QA sticker"is over the DRO.  There is a slot in the PCB next to the DRO.
There are four patch antennas adjacent to the electrical connection terminals.
The "IF" output is at audio, so I ordered a small "my amp" battery powered audio amp/speaker.
The can should face away from the target.  You can see the four antennas in Fig 3 on the PCB.

Fig 1
HB 100 10
                        GHz Doppler Module
Fig 2
HB 100 10
                        GHz Doppler Module
Fig 3 Two Tx antennas, two Rx antennas.
HB 100 10
                        GHz Doppler Module


I ordered a couple and they came as a single panel.  This unit does not have an IF output, only an On/OFF signal.  Intended to replace a PIR.
Frequency: ? GHz
Input: 4 to 28 VDC
Range: >5 ~ 7 meters (16' ~ 23')
GitHub: RCWL-0516 - 3.2 GHz, U1: RCWL-9196, The component side of the board should face the target.

EleCrow: RCWL-0516 Microwave Radar Sensor Switch Module Body Induction Module 4-28V 100mA -


3.3V Output
Normal: 0v, motion: 3.3V
4 to 28 VDC
LDR 10-20k Rl
U_LDR > 0.7V=On
Fig 1
RCWL-0516 3.2 GHz Doppler Module
Fig 2
RCWL-0516 3.2 GHz Doppler Module

See Ref 37.
 RCWL-0516 - 2.6 mA @ 5V, stock: 3 seconds on time, 100nF for 30 sec on time.
The IC is a custom version of the BISS001 PIR Controller (BISS001pdf).
The RF transistor is a BFR520 (BFR520.pdf) [marked 32W if made in China].
Building a USB powered PIR/Radar adaptor for LED strings -
Microwave doppler sensor lamp with perplexingly simple circuitry - eBay: LED Microwave Radar Motion Light Bulb
Inside another doppler radar microwave LED lamp - IC: EG4002C

CDM324 24 GHz Doppler Module

Frequency: 24GHz
Input: 5.5 VDC <= 40 mA
Range: 15meters (50')

IC Station: CDM324 24GHz Microwave Human Body Motion Sensor Module Radar Induction Switch Sensor - reverse engineering analysis

Fig 1
CDM 24
                        GHz Doppler module
Fig 2 Four Tx Antennas, Four Rx Antennas
CDM 24
                        GHz Doppler module


This is a packaged module.  The module has three terminals, ground, DC in and output.
The green PCB contains an LM317 to drop the input to the voltage required by the module and the two ICs.  It also has a relay and a terminal block with 4 contacts (input DC and output relay terminals.  In addition a green LED and a light sensor.  So this is aimed at controlling room lights.

Frequency: 5.8 GHz
Input: 12 to 24 VDC <= 0.5W
Range: 1 to 10 meters

Fig 1
                        5.8 GHz micrwoave switch
Fig 2
                        5.8 GHz micrwoave switch


2523455 Object locating system, William A Stewart, Philco Ford, App: 1944-05-30, W.W.II, Pub: 1950-09-26, -

2751589 Folded slot antennae, Cary Rex Henry John, National Research Development Corp UK, 1956-06-19, -

3394373 Combined oscillator and folded slot antenna for fuze useful in small projectiles, Stephen L Makrancy, Avco, 1968-07-23, -

3703722 Motion detection system with split-ring monostatic doppler detection, David N Gershberg, Alex Y Lee, E Systems, 1972-11-21, -

3845461 Intrusion detection system, D Foreman, Honneywell, 1974-10-29, -

                        Doppler radar module employing coupled
                        rectangular waveguides, John W. Davis, Radar
                        Control Systems Inc, 1977-08-16

4042934 Doppler radar module employing coupled rectangular waveguides, John W. Davis, Radar Control Systems Inc, 1977-08-16, - Very mechanical

                        Microwave motion-detection apparatus employing a
                        gunn oscillator in a self-detecting mode, Erno
                        B. Lutz, SOLFAN Systems, 1978-09-26

                        Gunn Diode Doppler module
4117464 Microwave motion-detection apparatus employing a Gunn (Wiki) oscillator in a self-detecting mode, Erno B. Lutz, SOLFAN Systems, 1978-09-26

The Gunplexer (Wiki)  is based on this hardware module.

Appears to be die cast, so low cost if the volume was high.

                        Transmit/receive microwave circuit, Yoichi
                        Kaneko, Kenji Sekine, Eiichi Hase, Akira Endo,
                        Hitachi, 1981-03-31

4259743 Transmit/receive microwave circuit, Yoichi Kaneko, Kenji Sekine, Eiichi Hase, Akira Endo, Hitachi, 1981-03-31 - Doppler speedometer

Monolithic circuit rather than parts on substrate.

                        Integrated oscillator and microstrip antenna
                        system, Vincent A. Hirsch, Ball Corp,

4736454 Integrated oscillator and microstrip antenna system, Vincent A. Hirsch, Ball Corp, 1988-04-05, -
                        Short-range radar transceiver employing a FET
                        oscillator, Cheng P. Wen, Richard T. Hennegan,
                        Hughes, 1990-06-05
                        Short-range radar transceiver employing a FET
                        oscillator, Cheng P. Wen, Richard T. Hennegan,
                        Hughes, 1990-06-05 4931799 Short-range radar transceiver employing a FET oscillator, Cheng P. Wen, Richard T. Hennegan, Hughes, 1990-06-05, - Duroid substrate, Gunn diode, power divider (not circulator) . FMCW so can detect range, not simple Doppler.

parts on substrate

                        Monolithic microwave transmitter/receiver,
                        Burhan Bayraktaroglu, Natalino Camilleri, TI,

EP0296838 Monolithic microwave transmitter/receiver, Burhan Bayraktaroglu, Natalino Camilleri, TI, 1996-03-27 - IMPATT diode (Wiki),

                        Relating to motion detection units, John
                        Konstandelos, Pyronix, 1999-11-02

5977874 Relating to motion detection units, John Konstandelos, Pyronix, 1999-11-02

EP3091605 Planar antenna microwave module, Hytronik Electronics, 2016-11-09

HP 35200A Doppler Radar Module

 In 1971 HP came out with the 35200A Doppler Radar module.  HP Measure Dec. 1970 - I remember we got one at Aertech for reverse engineering and were amazed that it had a design defect.  Fred called me to the microscope to see the bad design.  He was surprised that HP would make such a mistake.

HP Doppler Radar
                  module 35200A
The Gunn Diode (Wiki) and it's associated dielectric resonator (Wiki) form at 10.525 GHz oscillator with about 50 mW (+17 dBm) output.
It drives a circulator (Wiki) which passes signals in a clockwise direction.  Oscillator -> Antenna -> Band Pass Filter -> Mixer.

Note the the leakage from the oscillator to the Band Pass Filter will be down by 20 dB, or only 0.5 mW (-3 dBm) to the mixer.

There's a small amount of loss through the band pass filter making it a little worse.  That means the mixer does not have enough power to work and this product was a failure.

PS the HB 100 Doppler module that sells for under $3 on eBay uses a Wilkinson power divider (Wiki) to feed the same amount of power (about 13 dBm) to both the Tx antenna and the mixer.  That extra 10 dB of power (i.e. 10X) makes all the difference between not working and working.
Fig 1
HP 35200A Doppler
                    Radar Module
This is a very heavy device.  Note that the mixer pin has a shorting clip.  That means this pin is susceptible to electrostatic discharge (ESD).  Two more reasons why it did not become commercially viable.  The serial number is 00261.  Maybe less than 1,000 were ever made?

General Microwave

Stumbled on these General Microwave patents while learning about their radiation detectors.
5134411 Near range obstacle detection and ranging aid, Zdenek Adler, General Microwave, 1992-07-28, 342/130; 342/70; 342/128 -
Cites 9 prior are patents mostly concerned with FM-CW radar.
Cited by 51 patents.
5359331 Monostatic radar system having a one-port impedance matching device, Zdenek Adler, General Microwave,1994-10-25, -
5495252 Near range obstacle detection and ranging aid, Zdenek Adler, General Microwave, 1996-02-27, -

YouTube: 24GHz Radar Presence Detector that Works (LD2410), 13:18, 25 Sep 2022 - has firmware bugs, draws a lot of power so not suitable for battery operation.  Two modes of operation: use the on board uC which can be programmed (but with bugs) or process the sensor data yourself.
eBay search:  "LD2410"  many hits, starting price $5.20 for the PCB module. - but only the sensor board, none include the base PCB.
multiple sensors reviewed at: Home Assistant: mmWave Wars: one sensor (module) to rule them all -
The Seeed studio 24 GHz sensor not liked because of extreme sensitivity.  They also make a 60 GHz FMCW Human Resting Breathing and Heartbeat Module.
The Tuya Smart Human Presence Sensor uses the LD2410 module sells for about $30 in eBay. search term "Human Presence Sensor mmWave Radar" (5VDC @ 1 Amp)
OmniPreSense OPS243-C has WiFi and Bluetooth.

Aperiodic non tuned wide band receivers

The aperiodic and Sinitsa receivers are just crystal audio/video receivers and so belong on this RWR web page that's mainly about radar crystal video receivers.

The Bug Duster by Wenzel has a Sinitsa (Crypto Museum) mode of operation.  Some possible improvements: 

During W.W. II the aperiodic receiver was invented (see patent #2513384 below).  The SSR-201 (Wireless for the Warrior Vol 4) will receive any frequency between 50 kHz and 60 MHz without tuning, i.e. it's a wide open front end.  Also see the free on line book The History of the Radio Intelligence Division Before and During World War II. For example one of these was at the Japanese interment camp at Thule Lake, California (Wiki) and caught the man who had built a transmitter used to talk to other inmates who had regular AM radios.  They used radio transmissions to coordinate a escape attempt.

Below information based on inputs from Brian KN4R:
CIA Reading Room: D.F. Equipment - F.C.C. and F.B.I..pdf  -
* Finch model F-115-A: vehicle mounted, rotatable loop on roof (probably hetrodyne receiver)
* Fada Aperiodic receiver - suitcase size
* Kann Mfg. Co. series K Aperiodic - AC powered, relay to turn on recorder (see YouTube below).

YouTube: WWII Spy Locator Receiver - Aperiodic - Aperiodic Receiver, Type K4 Serial No. 70
Crypto Museum: SSR-201 - The SSR-201 "Watch-Dog"
AperiodicReceiver: Designed and Built by the FCC's Radio Intelliegnce Division During WWII -  the circuit diagram of the SSR-201 seems to indicate that it's essentially a crystal video type receiver.  The antenna drives a 1G4 tube operated as a grid leak detector (rectifier/crystal).  Followed by DC amplification that includes some audio frequencies.

Antique Wireless Museum: Patrolling the Ether in WW2 - Radio Intelligence for the War Effort, @33:25 Patrolling the Ether  - Series K aperiodic receiver, 50 kc to 60 Mc , all at once!, @43:08 "Patrolling the Ether" 1944 video
QST Oct 1944: Hams in the RID - Recording on Memorox magnetic paper discs -
The above two references mention magnetic paper disc recording using a "Memorox" machine, but I have not found the company. (see: Magnetic Recording/Memovox).
Let Me Know about Memorox.
Typo in October 1944 Issue of QST
Page 23:
Below - Transmissions being recorded on Memorox discs.  Each drawer beneath the amplifier includes a turntable and a magnetic recording head which embosses on paper based discs one hour and five minutes of playing time per side.  The operator here is transcribing signals which have been  previously recorded.
should be
Below - Transmissions being recorded on Memovox discs.  Each drawer beneath the amplifier includes a turntable and an electromagnetic recording head which embosses on paper based discs one hour and five minutes of playing time per side.  The operator here is transcribing signals which have been  previously recorded.

While the recording head is based on an electromagnet, it is misleading so say "magnetic" recording head since that would imply magnetic recording.
The recording technology is embossing plastic.

Note on page 19 (bottom left caption) got it correct: Memovox.
See: Magnetic Recording \ Memovox.

Test Equipment

Sweep Generators

In the beginning Aertech used Alfred Electronics BWO sweep generators, these literally could be used for boat anchors.  They were rack panel width and a couple of feet tall.  Later the HP 690 series sweepers with the plug-in BWO and snap in plastic frequency scale were used.  It was possible to put a number (3?) of plug-ins in one rack and the master in another in order to sweep more than one standard band (standard bands were AFAICR, L = 1 to 2, S = 2 to 4, C = 4 to 8, X = 8 to 12.4, K = 12.4 to 18, Ku = 18 to 26 GHz). Then the Kruse Stork 5000 solid state sweeper came out and it too had a combiner for multiband sweeps.  Then the HP 8350 sweepers came out with a single plug-in for multi-band sweeps and later multi octave band plug-ins.  These had poor phase noise, but for most microwave components work worked well.  You could tie two together for mixer work.  Then there were the synthesized sweep generators with excellent phase noise that were required for precision mixer work.

HP 415E SWR Meter

This is really a very narrow band AC voltmeter centered on 1 kHz.  Maybe a few Hz bandwidth.  When working with weak microwave signals you can 100% AM modulate the RF (either using the internal 1 kHz modulation feature of the sig gen or an external PIN diode modulator) then feed the output from a detector to the 415 meter.  Originally these were used for making slotted line VSWR measurements, but can be used for other applications.

HP 3400 True RMS AC Voltmeter

This is the only meter that I was aware of that could make such a wide band true RMS measurement.  Used for making noise measurements in a number of applications.

Also see my Microwave Test Equipment and Military Test Equipment pages for scalar and network analyzers, noise figure meters, &Etc.


I owe John, WA4WDL, a huge debt of gratitude for making me aware of this.  This came up while learning about the FuzzBuster and the early history of RWRs.  Note that the APS-nn designation is normally used for Airborne Search & Detection Radars. So the first part of this will be looking into the idea that this is a Radar Warning Receiver.  This unit is listed as:
"Tail-Warning Radar System; manufactured by ITT; used in B-47B/E, B-52, B-57A,B&C (On/Off, Delay: On/Off, Noes/Both/Tail, Audio Gaini, Phones On/Off, Test Momentary/Off, Power On/Off), EB-66B, F-101A/C (On/Off, Delay In/Out, Audio Gain; Nose/Both/Tail), F-105D, "EF-101B" (Canada)".

Thanks to Jan for copies of the B-571a,b&c manual pages as well as F-101A manual pages.  The functionality looks the same for both.  RADAR and visual sensors in both the nose and tail.  Audio with PRF into the AIC-1 audio system.


Wanted images of any part of the APS-54.  Let me know.
The below images courtesy of John, WA4WDL.

Fig 1 AM-924/APS-54 Amplifier, Video
                  Amplifier, Video
Fig 2 AM-924/APS-54 Amplifier, Video
                  Amplifier, Video

Note there are two Antenna Jacks and
two PRF Lower Limit Selector switches.
It may be that this is the heart of the system.
The antennas may have video outputs instead of RF.
See the AM-6536/ALR-54 RF box which has
video outputs.

What is it?

This is looking into the idea that this is a Radar Warning Receiver, rather than just an Airborne Search & Detection Radar.

The B-47 Stratojet Association - B-47B - "The B-47B carried a K-4A bombing navigation system with a periscope sight in a modified nose, AN/APS-54 warning radar, and AN/APT-5A electronics countermeasures devices"
Vietnam Conflict Aviation Resource Center - Martin B-57 Canberra - "Avionics:   – APW-11 Bombing Air Radar Guidance System, SHORAN bombing system (Wiki), APS-54 Radar Warning Receiver
3154780 Automatic SHORAN bombing system, Donald W Burbcck, Elwood E Bolles, Jr William E Frady, William L Exner, James D Hogan, Alfred D Scarbrough, AF, 1964-10-27, -
Joe Baugher - Martin B-57B - "An APW-11 (Radio Museum: 2.8 GHz)Bombing Air Radar Guidance System was provided, helping the pilot to make accurate runs into the target. The Shoran (Wiki) bombing system was added for use by the bombardier/navigator. An APS-54 Radar Warning System was provided, which increased the angle of coverage astern of the aircraft and gave the crew some warning of AI illumination."
QRC - USAF Quick Reaction Capability Programs - QRC-3: J band (Wiki: 10 -20 GHz) antennas for AN/APS-54 radar warning receiver; Hallicrafters; QRC-5: J band antennas for AN/APS-54 radar warning receiver; Hallicrafters, 1953; QRC-11 Selective J band antenna for APS-54 radar warning receiver, Hallicrafters, 1954
The Free Library - First pereson . . . singular. - "There was an APS-54 warning receiver, which was fairly new, and an ALE-1 chaff dispenser, which was not fully tested and which I was not allowed to use."..Col Joseph B. Tyra, USAF (ret.)
Amazon - RF-101 Voodoo Units in Combat (Combat Aircraft Book 127), by Peter E. Davies, Jim Laurier -
"I would have liked to see some coverage of the AN/APS-54 radar warning receiver,  that was replaced by the APR-25/26. The APS-54 was used until 1966 or 1967. It could handle the Fire Can (CIA: 2.7 - 2.86 GHz) and the Fansong (Wiki: S-75, SA-2: Fan Song: 2 - 3 GHz or 4 - 6 GHz) . The radar waveform was fed to the intercom as an audio warning. The APS-54 had two red warning lights on the instrument panel marked "Nose" and "Tail". I spent more time fixing APS-54 problems than my assigned job. The APS-54 had one antenna under the nose radome, and another on the rear tip of the vertical stabilizer cap. The BNC connector from the rear antenna to the stabilizer bulkhead had a habit of pulling apart. Repair usually involved standing on a step ladder on top of a Coleman "Tug" (Wiki) to remove the cap and repair the connector. One of the not so "fun" repair jobs.

The AN/AHN2 audio recorder is mentioned. This was used to record the Radar audio from the APS-54 for debreif and training. This was a Wire recorder. The recording wire was in a cassette. Wire breakage was frequent. You had to unsnarl the mess and splice the wire, then anneal it with a Zippo lighter. Wire recorders were long obsolete at that time. This one was probably used because it was smaller than the available tape recorders."
Radio Nerds - APS List - APS-54* ECM Warning Receiver for B-47,52,57,EB-66, F-101,105 Cape-Farns AS-679,680/APS-54 Antenna Units, 2600-11,000 MC


There may have been a couple of lamps on the pilot's instrument panel marked "Nose" and "Tail" that would light up if the system detected a high PRF (Wiki) indicating the aircraft was being tracked.  Note that search radars have low PRFs so they can have long unambiguous ranges, but tracking radars need fast PRFs to quickly detect changes in direction.

Patent 3500401 (see below) may be applicable?

A Guess at the system:


Based on Police Radar Warning Receivers.

1966 vector receiver (the small CRT showed the relative bearing to the threat as the angle from center screen, and the distance from center screen was a relative distance to the threat, made by Itek used to detect: S/X/C-Band Radar Detection and Homing Set; manufactured by Itek; part of AN/ALQ-27; used in A-7E, U-8, U-21, OV-1D, B-52G, RA-5C, A-6E, F-4, F-14, F-100, F-105, C-123, C-130

APR-25 APR-25
Also see the ATI Universal Bench Test Kit for the APR-25 and APR-26 as used in the B-52.

3500401 Radar
                  detection device, Gerald O Miller, Denman R Elliott,
                  Navy (China Lake), App: 1968-07-15,

3500401 Radar detection device, Gerald O Miller, Denman R Elliott, Navy (China Lake), App: 1968-07-15, Pub: 1970-03-10, 342/20; 375/339 -

A crystal video receiver feeds video pulses to a blocking monostable multivibrator with a 200 micro second recovery time so that the highest output frequency is 5,000 Hz.  In front of the detector is a shutter which when closed protects the detector from being burned out by a close by radar (like on an aircraft carrier when another fighter plane pilot turns on his RADAR even though he is not supposed to do that).  This is the case that triggered my development of the limiter-detector.

APR-25? or APS-54?

Patent Citations:
3061795 Flip-flop varies frequency of blocking oscillator, Clarence G Byrd, William K Hagan, IT&T, App: 1958-01-22, Pub: 1962-10-30, - "This invention relates to circuits for indicating the presence of a radio signal, and more particularly to a circuit for indicating the presence of a pulsed radio signal, the indication being sustained for a period of time longer than an individual signal pulse." So a human can hear radar pulses.

3094663 see above Microwave signal checker for continuous wave radiations 

Cited by:

3660844 Radar
                    detector and identifier, Basil E Potter, Sierra
                    Research Corp, 1972-05-02 
 3660844 Radar
                    detector and identifier, Basil E Potter, Sierra
                    Research Corp, 1972-05-02 3660844 Radar detector and identifier, Basil E Potter, Sierra Research Corp, 1972-05-02, 342/20; 455/117; 342/13; 455/229; 375/339 -
4 horn antennas, each for a different frequency band
Also CW and PRF detection,  Output by a number of lights and a single channel of audio

Requires more than 200 or 500 pulses per second.

This may describe the APS-54.

3671964 Automatic
                    radar detection device, Andrew J Trochanowski,
                    Steven A Wicks, Navy

3671964 Automatic radar detection device, Andrew J Trochanowski, Steven A Wicks, Navy342/20 -
blank screen for low pulse rep rates, but alarm and unblank for high pulse rates.

4181910 Portable
                    radar-detecting receiver, Allan B. Hitterdal,
                    Northrop Grumman Sys, 1980-01-01
4181910 Portable
                    radar-detecting receiver, Allan B. Hitterdal,
                    Northrop Grumman Sys, 1980-01-01 4181910 Portable radar-detecting receiver, Allan B. Hitterdal, Northrop Grumman Sys, 1980-01-01, 342/20; 343/774 -

4181910 Portable
                    radar-detecting receiver, Allan B. Hitterdal,
                    Northrop Grumman Sys, 1980-01-01

4440987 Computer and peripheral interface circuit, , Tandy Corp, AST Research Inc, 1984-04-03, -
audio frequency port for modem <-> computer coms

5361069 Airborne
                    radar warning receiver, Robert A. Klimek, Jr., Elias
                    A. McCormac, III, Ronald R. Schambeau, AF, App:

5361069 Airborne radar warning receiver, Robert A. Klimek, Jr., Elias A. McCormac, III, Ronald R. Schambeau, AF, App: 1969-07-18, (Vietnam Era - SECRET), Pub: 1994-11-01,  342/20-

6977611 FM-CW
                    altimeter detector, Ronald T. Crabb, Northrop
                    Grumman Sys, App: 1985-03-04

6977611 FM-CW altimeter detector, Ronald T. Crabb, Northrop Grumman Sys, App: 1985-03-04, (SECRET), Pub: 2005-12-20, 342/122 - detects the very weak FM-CW altimeter signal from aircraft well in front on plane on ground.  Maybe for IFF use?

7148835 Method and apparatus for identifying ownship threats, Jeffrey K. Bricker, Anthony J. Gounalis, James C. Rosswog, Stephen P. Wanchissen, Lockheed Martin, 2006-12-28, 342/20; 342/89; 342/195; 342/175; 342/13 - "A track indication may be provided that indicates at least one source is actively tracking the object based on the received signals and without adjusting the dwell arrangement of the scan strategy for the receiver."


crystal video Radar Warning Receiver made by Itek  Used to sense power-level changes in the L-band command guidance radars of the SAM i.e. a launch detector.
SAM launch warning system
SAM Launch Warning Set; manufactured by Itek; used with AN/APR-25; used in F-100, F-4, U-8, U-21


Homing and Warning ECM Receiver (improved AN/APR-25); manufactured by Itek; used in F-105, EF-4E, A-7, B-52, F-5E/F
IP-957/APR-36 - CRT display showing relative bearing to and type of threat by Applied Technology Inc (ATI) another view - Label -

"early A-10's used the IP-957/APR-36 azimuth indicator as part of the ALR-46 system and the indicator could display alphanumeric symbols as opposed to simple strobes."
- L.M.
YouTube: TD Wills: MilViz TacPack F-4E: AN/APR-36 RHAW System Demo -

IP957 APR36

ECM Signal
Can anyone define for me what the "BG06" SAM signal was and how the EWs "played" with it?  I'm a retired Lt. Col. who flew Ds as a Nav on CAR E-57 during LB II from Andersen.  B...  B,,,,,,

Re: ECM Signal
BG06 referred to the guidance channel for the SA-2 missile. The missile was tracked by the targeting radar and corrections to the missile were up linked to the missile via the BG06.

Since the BG06 antenna was "looking" back at the launch site, the only way to jam it was to be between the missile and the site. To do this, either you were below the missile doing support jamming or you were lucky and the missile missed you.

The radar warning receiver had a launch light to indicate the BG06 was active. My experience was that the light was inaccurate. I looked for the signal on my ECM receiver.

I an unaware of any way to play with it.



Radar Homing And Warning System; used in F-4G; replaced by AN/APR-47
YouTube: on F-4, no sound: MF 14 McDonnell Douglas F-4 Phantom II RPO demo flight test 2:48 -
F-4 Cockpit -


TM11-5841-283-12 Operation & Maint Manual, 150 pages,  is on line at ETM as PIN 053495.pdf
IP-1150 CRT eBay photo
YouTube: RCAF Library: CFSACO [V] 079 APR 39 XEI Demo -
AS-2890/APR-39(V), NSN: 5985-01-026-3927, Mfr: 33439 - is small blade type with SMA-f connector.


C-9326 Detecting set Control
IP-1150 Radar Signal Indicator
CM-440 Comparator
R-1838 Radar Receiver
AS-2892 (left) & AS-2891 (right) Sprial Antennas

AGM-45 Shrike Missile (Wiki)

Made by Texas Instruments.  There were a number of different seeker heads that could be installed, each for a different target (different frequency band).  I designed and oversaw the production of these Shrike missile detectors.  We made a set of 4 matched detectors for one of the heads.  The one shown is band IX (Wiki).  After properly torquing the SMA nut on the RF (bottom) end a tube with a flange was slide down and the O-ring seated on the tube ID.  The flange was bolted to the guidance section to support the detector in the high vibration environment found on an aircraft wing.  A computerized test system was used to measure hundreds of detectors at a time and output the serial numbers of the matched sets.  We could match much better than the spec using this system and it improved our yield.  (Another version of this test method was later used by ST Microwave to match detectors for a satellite program to extremely tight tolerances.)

Since the frequency band was determined by which guidance section was installed on the missile, the target needed to be known before take off.This problem was solved by the HARM missile.

An ammunition reloading press was used to seat some of the SMA connector pins by meas of a custom die.
4336739 Bullet seating die, Kenneth L. Alexander, Ammunition Accessories, 1982-06-29, -

The Shrike has the bang-bang (Wiki) steering vanes located at the center of mass of the missile.  This also causes the AIM-7 Sparrow missile (Wiki) to move sideways rather than to rotate.  Bang-bang control was also used on most W.W. II vintage torpedoes.

Warfare History Network: Wild Weasels and the AGM-45 Shrike Missile -
Wiki: Anti-radiation missile (ARM)
Also see my China Lake Patents: Shrike web page.

3683385 Direction finding antenna system, U.S. Navy
China Lake, CA,
Aug 8, 1972, 342/447, 343/895

The four detectors are 17, 17', 18 & 18'
3712228 Target marker warhead
China Lake, CA,  Jan 23, 1973
replaces the warhead with a marker
making it easier for others to bomb.
AGM-45 Shrike
                    anti-radiation missile patent 3683385 3712228 Target marker warhead China Lake, CA, Jan
                  23, 1973
In the YouTube video "The origins of ARM. Defense suppression and the AGM-45 Shrike antiradar missile" see Ref 14@6:50 they mention "Dip Angles" & "Line Up Your Needles".  I think the instrument is an ADI with the needles wired to a Shrike interface.  One needle for Left-Right and one for Up-Down.  The plane/missile needs to be pointing at the antenna that is to be the target.
Shrike ADI
What is this instrument?
Let me know.
There's many Shrike patents on the China Lake web page.

YouTube: janssen70: AGM-45 Shrike -

AGM-88 High-Speed Anti-Radiation Missile (HARM) (Wiki)

AN/ASQ-213 Harm Targeting System (Wiki, FAS) - F-15 block 50/52

Made by Texas Instruments.  Instead of using detectors tuned to specific threat frequency ranges the HARM has a wide band mixer that can be electronically tuned to the desired frequency.  It's a Superheterodyne receiver (Wiki) not a crystal video receiver.

This is the system where we used the HP 8566B spectrum analyzer to directly measure the spurious mixer products very quickly.  This system was in an access controlled room and had a number of security features.  The test time was reduced dramatically compared to manual testing.  The HARM could be tuned to any desired frequency so one missile could be used for whatever target came up.  Unlike the Shrike AGM-45 above where the seeker head determined the frequency of the radar target.
7 Aug 2022: The Drive: Does Ukraine Now Have AGM-88 High-Speed Anti-Radiation Missiles? (Updated) -
8 Aug 2022: Anti-Radiation Missiles Sent To Ukraine, U.S. Confirms - "...we've included a number of anti-radiation missiles that can be fired off of Ukrainian aircraft."
Air Power Australia: Texas Instruments (Raytheon) AGM-88 HARM -
"The AGM-88 can detect, attack and destroy a target with minimum aircrew input. The proportional guidance system that hones in on enemy radar emissions has a fixed antenna and seeker head in the missile nose. A smokeless, solid-propellant, dual-thrust rocket motor propels the missile." Ref 22.

Explanation of HARM on soviet block aircraft v. on the F-16, see Ref 29.


Replaced by the ALR-67 (Wiki). YouTube: ALR-67 F-18s Threat Warning System 1975, AN/ALR-69 (RWR) F-16 1970s, AN/APR-39A AH-64, 1:22 -

2-18 GHz Radar Warning Receiver; manufactured by Litton; used in F-8, F-14, A-4, RA-5C, A-6, EA-6B, A-7, F-100, F-4, F/A-18, CF-104 (Canada)
I think this is the one that we made all the Limeter Detectors for?
Control - Close Up - Label - 3 buttons for enabling or bypassing the lo, med and high frequency bands, also 3 buttons for Built-In-Test of the three bands and these double as AAA, AAA/AI or AI selectors?


Digital Warning Receiver; manufactured by Litton; used in B-52H, A-7D, A-10, C-130, F-104, F-105G, F-111, F-4, F-5E/F, RU-21H, OV-1, OV-10, HH-53


long-range homing receiver


Until I found this unit on eBay I didn't know the Limiter Detectors we made were used in the ALR-54, but they are.
Radar Warning Receiver for "LAMPS I" system; manufactured by Itek; used in SH-2D/F, SH-3G/H
The AM-6536 uses a number of Aertech Limiter Detectors.
Sikorsky S-70B Seahawk - "Light Airborne Multipurpose System (LAMPS)"

I found the AM-6536/ALR-54 on eBay.  From the photos it looks like the box where the air frame coax cable from one antenna goes to a single TNCm input connector on the AM-6536.  Inside there's the band separation filter and I think this unit has 4 Limiter Detectors.  There's 5 video amplifier boards and some other board with 5 channels, maybe threshold and slope adjustments.  Some reverse engineering will be interesting.  This unit has had a hammer taken to it and it's been stored outside for some number of decades, but I expect it still may be in almost working condition.

Uses the A9X141, A9X142, A9X143 and A9X144 Limiter Detectors.  The overall AM-6536 box has a contract date of 1972.
Dimensions: 6.0 x 6.75 x 3.25 inches  Box made by machining a billet of aluminum that size to remove the cavity inside.  Four of the Video PCBs are fed by the four Limiter Detectors and one video PCB (XA5) gets it's input from the external TNC-male coax connector and since the coax on the inside of that connector has no shield for about 1 inch and it feeds a video amp I'd say it was a fairly low frequency video signal, not RF, not microwave. What was it? let me know

This box was part of the very first LAMPS and has been sitting outside with a cover removed for many decades.  A couple of the transistors on one of the Video PCBs have had their leads rust away allowing the transistor body to be missing.  The conformal coating could not get between the bottom of the transistor and the plastic spacing disk.  The rest of the board where the coating is in tact looks good.  No op amps, no ICs, just discrete parts.  Not sure what the white growth on the aluminum is, but suspect it's related to a salt water atmosphere.

Need to put together a time line for Aertech.  If you know key dates in Aertech's history please let me know.


Used on the F-111
Antenna: AS-2943/ALR-62


0.5-18 GHz Multiband ECM Receiver (improved AN/ALR-59); manufactured by Litton; used in E-2C


(also called the LR-100), a lightweight radar signal receiver designed in-house by Litton Amecom using COTS (commercial-off-the-shelf) components. It can serve as a radar warning receiver (RWR) and also provides precision emitter location and identification (ESM/ELINT) as an electronic support measures (ESM) system.

AN/AAR-60 MILDS (Missile Launch Detection System) (Wiki)

Is Ultraviolet light based.
also see IR/FLTS Patents

Multi-band Filters

All of the Limiter-Detectors I worked on ended up attached to a multi-band filter, typically called a tri-plexer or quad-plexer.
3215934 System for quantizing intelligence according to ratio of outputs of adjacent band-pass filters, Roy P Sallen, GTE Sylvania, 1965-11-02, -

Polar Frequency Discriminators =  Instantaneous Frequency Measuring

This microwave component is composed of a combination of power spliters and couplers and contains 4 detectors.  One pair of detectors provides an X value and the other pair provides a Y value for a vector.  The magnitude of the vector is proportional to the amplitude of the incoming signal and the phase angle is proportional to the frequency of the input signal.  In order to get higher frequency resolution you can combine a number of these using delay lines that are increasingly longer so that the frequency is read using a gas meter approach.  In this way you can make an instantaneous frequency measuring (IFM) receiver.  Note that this receiver can determine the frequency of an incoming signal on only one pulse.   We made a number of different models of this device.  they have a frequency range that's no more than an octave, else there would be a frequency ambiguity.
Wide Bnad Systems - makes these
WJ App Note: High Probability of Intercept Receivers in an EW Environment -

W.W. II Glide Bomb

Not really RWR, but this is the closest web page.  Also see China Lake Patents\Air to Ground Missiles

Wiki article on Bat (guided bomb).  Patents:
Class 244 Aeronautics and Astronautics
    3.2 Missile Stabilization or Trajectory Control

2764698 Control System, Filing date: Nov 23, 1942 - optical system to control glide bomb
2680578 Glide Bomb, Filing date: Feb 17, 1945 - TV guided
3128061 Automatic self-guidance System for Movable Objects, Filing date: Aug 11, 1945 Issue data Apr 7 1964 -
uses 4 quadrent optical system
1352960 WIND-WHEEL ELECTRIC GENERATOR - for farm use
1387850 SYSTEM OF RADIODIRECTIVE CONTROL - "...a boat, air craft, vehicle, or revolving lighthouse..."
1388932 Arial Torpedo - photocell guidance for attacking a ship
1447646 Selenium Cell or Bridge, C.W. Cherry - 4 quadrants - also see 594 Photronic cell
1747664 Apparatus for Automatically Training Guns, etc. on Moving Objects - 4 quad optical sensor
2070178 AIRPLANE NAVIGATING APPARATUS - uses IR so works in fog as well as daylight
2165800 DIRECTION CONTROL DEVICE - radio remote control
2300742 MEASURING AND CONTROL APPARATUS - prevents hunting
2377589 AUTOMATIC AIMING CONTROL - for a gun, uses 4 telescopes and photocells
2403387 RADIANT ENERGY RESPONSIVE DIRECTIONAL CONTROL - quadrant photocell bomb steering
2404942 STEERING DEVICE (RCA) 1940 - a beam with 4 quadrents is aimed at a ground target and the bomb is steered by the beam.
2417112 ELECTRICAL CONTROL SYSTEM, Kettering (GM) Filing date: Jul 3, 1943 - heat seeking aerial bomb - also see Kittering Bug
2421085 TARGET SEEKING AERIAL BOMB, (Bendix), Filing date: Jul 12, 1943 - works with reflected IR
2424193 SELF-STEERING DEVICE - 4 photocells
2425558 Direction Control Device, - radio control, very heavy and complex
2431510 Photocell Multiplier Device, (Farnsworth Res), Sep 29, 1944 - photo-multiplier tube with 4 quadrants
2457393 Apparatus for Causation and Prevention of Collisions, G. Muffly, - anti aircraft missile, 4 photocells


When I joined (about 1963) Aertech was at 250 Polaris in Mountain View.
196? Aertech moves to 815 Stewart in Sunnyvale (or 825 then 815?)
1968 Aertech at 825 Stewart in Sunnyvale
1984 TRW buys Aertech and even though the FSCM number stays 21847 the name changes to TRW Microwave.
__?__ Deguigne Dr. was another Aertech Building on the corner of Thompson Place.  Across Thompson was AMD.  At the end of Thompson was a heliport, but it was not used.
1987 FEI buys 21847 and the name becomes FEI Microwave
1992 (?) most people are laid off and part of Aertech moves to ST Microwave.
EPA Region 9 Super Fund sites - 825  Note that it's very difficult to tell what building is causing pollution since the ground water moves it.  The only way is to have test wells on at least 4 sides of a building and compare the upstream contamination with the down stream, if they are the same then it's not your building.  Driving around the block of Stewart you can count dozens of test wells.

Radar Countermeasures

Flares are a counter measure against heat seeking missiles, like the Sidewinder (See China Lake Patents). Chaff (UK: Rope) is a countermeasure against radar.
There are electronic countermeasure equipment.

2440253 Pulse radar interference producer, Sven H M Dodington, Standard Telephone and Cables, App: 1944-07-04, SECRET, Pub: 1948-04-27, 342/15 331/51 331/144 327/100 -the oldest patent in class 342/15. - cited by 25 patents.
3019433 Radar countermeasure, Stanley B White, 1962-01-30, 342/15 - invented Link Trainer stuff.
3118638 Decoy for guided missiles, Fred H Rohr, 1964-01-21, 244/3.16; 102/374; 102/348 - radio/radar & IR

Flares (Wiki)

Chaff dispensers typically are also used for flares (Wiki).  They are a defense against infrared homing missiles like the Sidewinder developed by China Lake Naval Weapons.
See YouTube for examples of the F-18 launching flares.  This may be what the F-18 intended to do prior to the crash involving a KC-130 tanker.
AP - 2 US warplanes crash off Japan; 1 crew dead, 5 missing, December 6, 2018 -
ProPublica: Faulty Equipment, Lapsed Training, Repeated Warnings: How a Preventable Disaster Killed Six Marines - Video: Adrift- How the Marine Corps Failed Squadron 242 12:11

Also see China Lake Patents Ref 48, page 30 Onboard Thermal Jammer (ALQ-144 & L-166-11E) and page 46 Pyrotechnic flares
China Lake Patents Ref 51.  GENESIS of INFRARED DECOY FLARES The early years from 1950 into the 1970s

M-206 Flare, Aircraft, Countermeasure

This has what appears to be a form and fit equivalent of the M-1, Chaff, Countermeasure
1" square body 8" long.
From China Lake Patents Ref 51: page 48.

M-206 Aircraft Decoy Flare: This is an Army flare, which nominally is 1-inch by 1- inch by 8-inches in size. It is used by both fixed and rotary-wing aircraft.

Fig 1
M-206 Flare,
                  Aircraft, Countermeasure
Fig 2
M-206 Flare,
                  Aircraft, Countermeasure
The M-206 Flare has been fired, the tube is empty.  It has fired impulser (primer).  The impulser is electrically triggered rather than triggered by a firing pin.

The M-1 Chaff stick has not been fired, it contains the payload, but is missing the impulser (primer), so is ready to be used.

They are sitting on top of a couple of RR97/AL Chaff Bricks.
Fig 3 Impulser removed from M-206 flare.
Note held in by O-Ring.
Body dia: 0.495"
Body overall Length (excluding blown paper): 0.519
Flange thickness: 0.045"
Flange dia: 0.620"
Center contact recessed: 0.068"
M-206 Flare,
                  Aircraft, Countermeasure
Fig 4 Marked:

M-206 Flare,
                  Aircraft, Countermeasure

Impulser is electrically fired.

MJU-32A/B Infrared Decoy pyrotechnic Flare

Initially I posted this paragraph on the 40mm grenade web page because the shape of the MJU-32 looked like a 40MM round.  Also see the AN-M8 Flare Pistol.
But the igniter has the look and feel of those used on aircraft Chaff and Flare cartridges so this belongs here. 

Flare, Decoy
1370-01-592-1440  LA49

The body OD is 36mm (1.4") and overall length is 148mm (5.8").
The flange at the rear is 1.66mm thick and 37.8mm dia (1.488").
But instead of a small arms primer socket there's what appears to be a recess similar to that used with Chaff and Flare cartridges used in countermeasures.

From China Lake Patents Ref 51: page 68.

MJU-32/B Aircraft Decoy Flare: This MTV extruded flare is an improvement of the MJU-8A/B flare. It also is 1.43 inches in diameter by 5.81 inches long. The lacing of the spaghetti into the longitudinal holes of the grain is a very labor-intensive procedure. To reduce the labor cost, the holes were changed into a “T” shaped slot. Spaghetti no longer is required in this design. The concept of the “T” slot is that it would undergo fissure burning and there would no longer be a need for an igniter material in the slot. After many experiments with the shape of the slot, the final “T” shaped slot was chosen as the optimum balance between ignition speed and performance. Mr. Jeff Mulinix of NSWC Crane is the inventor of the “T” slot. This flare dates from 1995.


It appears that flares/chaff with nomenclature starting with MJU- can be used in either the ALE-39 (Citizendium) or ALE-47 (Wiki, Citizendium)  The ALE-47 Counter Measures Dispensing System (CMDSS) is a replacement for the ALE-39 CMDS (FAS).  The magazines that hold the round MJU-32 may be interchangeable with the magazines that hold the square M-206 Flare or M-1 Chaff sticks.  The former is a 1.4" diameter round package and the later is a 1" square package.  But the photos I've seen show a 5 x 6 array for a total of 30 cartridges.  They are all square or all round.

The ALE-39 made use of an intervalometer (Wiki) to dispense the flares.

H1603H Flare with safe-and-arm ignition system, Dennis D. Deckard, Stanley J. Herold, Donald E. Lagrange, Dennis L. Mitchell, David J. Mulinix, Navy, 1996-11-05, -

6679174 Flare igniter with a slurry groove, David J. Mulinix, Navy, 2004-01-20, -
                  Methods and apparatuses for active protection from
                  aerial threats, Northrop Grumman, 2019-10-03, -
This is an enhancement of the ALE-47 that launches rockets instead of chaff or flares.  At first I thought it was the ALE-47, but that's not the case.

20190301839 Methods and apparatuses for active protection from aerial threats, Northrop Grumman, 2019-10-03, -

Fig 2A existing 5x6 ALR-47 magazine holding 30 round cartridges.

Fig 2B is the Eject Vehicle (EV) rocket which is the same size as the existing ALR-47 round cartridge.

The AN/AAR-47 Missile Approach Warning System (Wiki) can trigger the ALE-39 or ALE-47 to launch IR countermeasure flares.  Note the AAR-47 works by detecting the UV signature of the approaching missile.

Fig 1
MJU-32A/B Decoy
                  pyrotechnic Flare
Fig 2
MJU-32A/B Decoy
                  pyrotechnic Flare

Global Security has a page for the MJU-32B Infrared Decoy Flare. "The MJU-32/B Infrared Decoy Flare devices are magnesium-teflon based and produce the same fire ball result as the Mk46 Mod 1c infrared (ir) decoy flares but incorporate a safer igniter design that requires an external ignition source."

The MK46 MOD 1C Decoy Flare is being replaced by the MJU-32/B through attrition.
From Navy Study Material 14313A:

These decoy flares are conventional pyrotechnic Magnesium/Teflon/Viton (MTV) flares that are utilized to decoy IR heat-seeking missiles. These flares are launched from the AN/ALE-39 Countermeasure Dispensing System and AN/ALE-47 Countermeasure Dispensing Set.

The MJU-32A/B and MJU-38A/B are form, fit, and function replacements for the MJU32/B and MJU-38/B. Improvements were made to ignition reliability. These decoy flares consist of a cylindrical aluminum case approximately 5.8 inches long and 1.4 inches in diameter (Figure 4-13).

The base end of the one piece flare case is flanged to a maximum diameter of 1.495 inches to fit the counterbore in the chamber of the dispenser block. The end of the flare case opposite the flanged base is closed with an injected molded polycarbonate end cap attached by a 360 degree crimp. The MJU-32A/B and MJU-38A/B have a (Black) plastic cartridge retainer threaded and sealed into the base of the flare case.

These decoy flares consist of two major elements: the pyrotechnic composition (or flare grain) and the igniter assembly. In the MJU-32/B and MJU-38/B, the complete length of the grain is wrapped with adhesive backed aluminum foil that extends over part of the igniter.

In the MJU-32A/B and MJU-38A/B, the adhesive backed aluminum foil is one-inch wide and covers the gap between the grain and igniter assembly. The igniter assembly contains a plastic body, two ignition pellets, and bore sensing sliders. A silicone rubber pad is located between the end of the flare grain and end cap to provide for variations in longitudinal dimensions of the parts with time. It also provides protection for the internal parts by damping vibration and shock forces. This device requires the CCU-136A/A impulse cartridge for functioning.
MJU-32A/B Infrared
                  Decoy pyrotechnic Flare

Chaff (Wiki)

A RADAR countermeasure developed during W.W.II was then called Window by the British, but Chaff (Wiki) by the U.S.  This consisted of thin strips of Aluminum foil cut to be a half wavelength long.  The trouble was that the strands tended to stick together.  The solution was to use small diameter glass fibers with a metallic coating.  These do not stick together and you can get a lot more of them in the same dispenser volume.
German words that may be related are Düppel or Kunstfadenstraengen.
By 1957 tactical aircraft had Radar Warning Receivers and Chaff (Ref 2). 


In W.W.II a long strip of chaff was called rope.  This was used to confuse long range search radar sets that operated in the HF or VHF frequency range where a 1/2 wavelength is much longer than required for a microwave radar.  This was on eBay with title: VTG Genuine WORLD WAR II CHAFF to Confuse Radar 70 Years Ago - WWII - It appears to be many feet long.
3" x 3" x 5/8" - Does not look like any common dimensions with the RR-97/AL Chaff Brick.
Tape dimensions (see Fig 4).
Plain leader tape thickness: 0.009"
Plain tape wrap radial thickness: 0.110"
Plain Tape ID: 2.80"
Foil tape is in two layers total thickness: 0.001"
Foil Tape OD: 2.775"
Foil Tape ID: 1.422"

Roll Length Calculator:
Plain Tape: 2.8 Meters long, 12.2 Turns.
Foil Tape: 113 Meters long, 676 Turns.

Fig 1 Three wraps of paper to form a streamer.
Chaff Rope
Fig 2
Chaff Rope
Fig 3
Chaff Rope
Fig 4

Chaff Rope

Chaff Brick RR97/AL

This thick paper package (5" x 3" x 2") seems to be designed to tear apart when in windy conditions, like being ejected from an aircraft.  There is a trigger string (see Fig 4 and Fig 5) which I suspect trips a mouse trap (Wiki) mechanism that spreads the contents of the aluminum box.  If you know about these let me know.

Note 3"x5" comes about from the used of the Calculagraph to keep track of the hours worked, i.e. a factory time clock.  The card size was 3x5.

The thing that's strange is that these contain aluminum boxes which could damage someone after falling out of the sky.   All the other chaff products I've seen would be harmless to anyone on the ground, but not this one.  Why?  Let me know.

Fig 1 Marked:
RR97/AL (standard nomenclature for chaff container)
190565 (maybe 19 May 1965)
7S7M ?
AF33/657/12145 (AF contract number?)
Fig 2
Fig 3
Fig 4
Fig 5 stamped: 63 C3030

Half Brick P99 770

The eBay seller claimed this was Korean war vintage, i.e. the SA-2 (Wiki) was in use so the Fan Song (Wiki) might be the indented radar which operated between 2 and 8 GHz.

Outside dimensions: 5" long x 3" wide x 7/8" thick.
There are seven different lengths of chaff.
See:  Omni Calculator: Dipole

half wave dipole

Chaff P99 770

Chaff P99 770 The internal pack width (chaff length) are left to right:
Top Row: 7/8", 1-3/8", 1-1/16" & 1-1/4"; total: 4.5625"
Bottom Row: 2-1/8", 1-1/2" & 1"; total: 4.625"

M-1, RR-170AL Chaff Countermeasure

This is a stick type chaff cartridge maybe introduced around 1977.
NSN 5865-01-048-2137
p/n: 9311402
RR-170/AL used on: F-4, F-5, F-15, F-16, A-7, A-10
M-1 used on:Army helicopters
made by Armtec.

1" square body 8-1/8" long.
Fig 1
M-1, RR-170AL
Fig 2
M-1, RR-170AL

Table of Chaff Cartridges

"Countermeasures Chaff Container" may be the correct way to refer to this brick.  Found this information using that search term:
Global Sec
dia x len
Chaff In.
Freq GHz
Easterline NSN

2.5 - 10.5
1958 from Ref-1, 16 oz, foil,


2.5 - 10.5 1958 from Ref-1, Fiber, 3 oz



0.3 - 0.6



2 - 18

5865-00-929-6095 ALE-29A
Mk 46, MJU-8B
1.25x5.8 CCU-136/A
2 - 18


Cyl 1.25x5.8 CCU-41/B
8 - 18
5865-00-160-3964 ALE-29A

1.4" x 6"
1.25x5.8 CCU-136/A

6 - 18 H, I & J bands




A-10, B-l, F-15, F-16, C-5, C-17, C-130, and C-141



2 - 18
1370-01-037-8414 M-130


2 - 18

2 - 18 starting 1990, uses Navy 1x2 stick


NAVAIR 11-120-20 NSWC Crane Draft 1999 Airborne


replaces paper box with plastic box


8 - 18 A-10, F-15, F-16
M206 1x1x8

Ref 1. Chaff Countermeasures and Air Defense RADAR Design, SRI, April 1959, dtic 354894.pdf,
Ref 2. The Air Force in Southeast Asia: Tactics and Techniques of Electronic Warfare, B.C. Nalty, Aug 1977, AFD-110323-034.pdf -

Chaff Dispensers

These bricks do work in the D-21/ALE-27 (Wiki).  These were used in aircraft where the AN/ALR-46 was used, so about equal vintage. 
Overall 39" long x 7" high x 6.5" wide.  Each of the two magazines has about 36" internally available for expendables.  So for a 2" thick package like the RR-97/AL each row can hold about 18 bricks or 36 bricks total.

Fig 1 Handles fold up to make it easy to carry.
Left end is solid.
Right end has holes shown for pusher.  Exit port on bottom.
Fig 2 The two rusty screws at bottom center
of each hole are the package rippers.
There are sheet metal center strips on each side
(2 shown below) between the gear tracks to hold the
expendables slightly away from the tracks.
Fig 3 Trolley to push packages to exit port.
Fig 4 RR-97/AL shown sitting on trolley.
The narrow tie shown pointing up so that
ripper can tear package open.
Fig 5 A ripper for each of the two magazines.
Fig 6
Fig 7

eBay Fig 1
Any electrical interface? No.  This is the Dispenser D-21 which is a part of the ALE-27 system.

eBay Fig 2
The illustration matches the look and feel of the RR-97/AL.

eBay Fig 3
Chaff Dispenser Magazine and Feeder
Mfgs. p/n: 30-1050-1    s/n: 5468
Stock No. 5895-012-7468EA (NSN)
Type:  D-21/ALE 27
Cont. No. OC-65-2  AF36(600) 19515  (1965 Contract date)
Weight:  23.25 lbs.
Proterty of U.S. Gov't.
Electronics & Systems Inc.
Glen Head, N.Y.
Stamp on black paint:  ASS'Y F.T. Feb 11 1965 (data of Fungus Treatment)

eBay Fig 4

The ALE-24 may be the first generation system?
Lundy Electronics & Systems is listed in the 21 October 1989 issue of Electronic Warfare Directory on page 49 showing the ALE-24, ALE-29 (RR-129/RR-144 cartridges, Mk 46/Mk 47 IR flares), ALE-32, ALE-43 (Chaff cutter), ALE-44 (RR-129/Mk 46 flare).

An upgrade of the ALE-39 & ALE-40 dispenser.  The ALE-47 (BAE Systems) may be the a more modern dispenser.
1985 - 1986 the ALE-40 had a problem with inadvertent releases and that was fixed in a 1987 modification.


This would be the first of the ALE Chaff countermeasures sets.  The eBay seller guessed it was from a B-52.
After taking off the rear cover (single Dzus fastener Wiki)) there is a data plate.  Maybe this was to hide what it was.  In the UK they treated Window with a lot of secrecy.

Data Plate:
Control, Countermeasures Chaff Dispenser
Type: C-1280/ALE-1
Govt spec: MIL-D-25180
Volts DC: 24-29
Amps: 6
Contract No.: AF 33(600) 29810
USAF Stock No.: 1660-036 290 571
Mfrs Part No,: G36X6012
Mfrs Serial No.: AF-55-3079
Webster-Chicago Inc., Chicago, Ill., US Property

Webster-Chicago had many patents related to: phonograph players, wire recorders & tape recorders, but none that I could find related to Chaff Dispensers.

Smithsonian National Air and Space Museum: Intervalometer, Countermeasures Chaff Dispenser, TD-93, AN/ALE-1
Data Plate:
Intervalometer, Countermeasures
Mfr's Part No.: RD15100
Type: TD-93/ALE-1
Mfr's Serial No.: AF 54-4491 (?)
Volts DC: 28
Order No.: AF 28063
Stock No.: AF 1660-03/5/4036
Amps: 12
Ryan Industries, Inc. Detroit, Michigan, U.S. Property
                  Intervalometer, Countermeasures
Photo from Smithsonian National Air and Space Museum

Has three 14 socket connectors that look very much like J102.  They are marked:
D Output D-1/ALE-1 or D-2/ALE-2 Output C (for the left two connectors)
A-6 Output B



3 mail pins
Panel Connector: Amphenol 14S-7, 7/8 male thread
Cable Connector: TBD
+28 VDC Input
28 VDC Panel Lights 3ea parallel GE 327


14 sockets
L 20-27 N

Switched DC to Dispenser
Intervalometer Switch
Blue Intervalometer Switch
Red Intervalometer Switch
Green Intervalometer Switch
Green Intervalometer Switch
Blue Intervalometer Switch
Red Intervalometer Switch
Green Signal Lamp & Counter




Controls& Indicators



Continuous: Positions: 1, 2, 3, 4, 5 & 6 - What do the numbers mean?
Intervalometer Positions: A, B, C, D, E & F - What do the letters mean?
A total of 12 Positions

Signal Lamp & Chaff Reserve

Every time a chaff package is ejected the Signal lamp flashes and the Reserve counter decrements by the number of packages ejected (not clear since meaning of Switch is not clear).

Fig 1
Fig 2
Fig 3 Data plate under rear cover.
Fig 4 Down Veeder-Root Counter.

Hackaday: MILSPEC Teardown: C-1282 Chaff Controller - Includes a short video where the lights and counter are triggered.

Boeing's B-47 Stratojet by Alwyn T. Lloyd - pg 237 shows ALE-1
B-52 Stratofortress vs SA-2 "Guideline" SAM: Vietnam 1972–73 yy Peter E. Davies - pg 18 B-52G shows the ALE-1.
World electronic warfare aircraft by Martin Streetly - pg 117 lists
AN/ALE-1:  B-47, B-52 and B-66.
AN/ALE-2: F-100, RB-57 and T-33

The History of US Electronic Warfare: "The renaissance years, 1946 to 1964" by Alfred Price - pg 70: "The ALE-1 was an improved version of the A-6, with a more powerful motor and a more effective system of rollers to ..."

Chaff, Flare, Launcher Patents

2476302 Self-propelled projectile for distributing material, Morris R Jeppson, Army, 1949-07-19
2489337 Aerial reflecting signal target, Sperling Jacob George, US Sec War, 1949-11-29 - allows radar tracking of weather ballons
2832507 Dispensing apparatus, John W Beatty, App: 1953-06-05, Pub: 1958-04-29, 221/112; 221/185; 221/244; 221/253 -
2856185 Dispensing mechanism for packaged window material, Fred L Whipple (Wiki, Ref 31), USAF, App: 1952-01-16, Pub: 1958-10-14, 221/73; 206/820; 221/32; 225/99 - removes tape from cardboard bricks
2859896 Chaff dispenser Francis M Johnson, USAF, App: 1956-07-20, Pub: 1958-11-11 221/112; 221/253; 221/244 - mechanism for dispensing bricks
2881425 Method of producing radio wave reflector cords of varied length, Charles A Gregory, USN, 1959-04-07, 342/12 -  metal coating on tissue, cellulose, nylon, or other light weight non-conducting material
2898588 Attack deviation device, Connelly L Graham, Northrop Grumman Corp, 1959-08-04,
342/8; 342/9; 273/360 - radar reflector towed behind aircraft
Metal coating of glass fibers at high speeds, John B Eisen, Nachtman John Simon, Bjorksten Johan, Lawrence A Roe, Bjorksten Res Lab Inc, Oct 6, 1959, 65/446, 65/475, 65/468, 118/DIG.220, 264/DIG.190, 65/453
2951410 Tape cutter, Harvey J Brown, Lundy Electronics & Systems, 1960-09-06, 83/304; 83/344; 83/582; 83/595; 83/342; 83/345; 83/591 - ALE-43
2954948 Chaff dispensing system, Francis M Johnson, USAF, App: 1956-04-10, Pub: 1960-10-04 244/136; 221/7; 221/243; 221/15; 221/277 - "..holds a stack of boxes or packages of chaff which are to be dispensed." - may jam when gravity points other than to bottom of box (see 4650092 for improved box dispenser)
2957417 Missile decoy, Daniel D Musgrave, (not assigned), 1960-10-25, 244/3.16; 342/9 - bomber launched defensive missile
3023703 Chaff dispensing device, Beatty John William, 1962-03-06 - based on a 2-3/4" rocket (Wiki)
3027047 Chaff tape cutter, Francis M Johnson, USAF, App: 1956-04-27, Pub: 1962-03-27, 221/30; 83/355; 83/357; 83/923; 102/505; 221/25; 221/73; 342/12 -
3095814 Dispensing apparatus, Tor W Jansen, William B Walker, Navy, 1963-07-02
Fiber winding and fabricating method and machine, Drummond Warren Wendell, Bjorksten Res Lab Inc, Aug 20, 1959, Feb 11, 1964, 156/181, 156/433, 156/166, 28/290, 156/425, 28/289
3126544 W.H. Greatbatch Jr, (not assigned) March 24, 1964, 342/9; 342/12 - lists prior art countermeasure systems - forward fired target missile
3137231 Chaff dispenser system, Francis M Johnson, USAF, App: 1956-06-08, Pub: 1964-06-16 102/351; 342/12; 102/505 - pod with rockets that can be fired ahead of aircraft.
3143965 Chaff dispenser, Pointe Andre E La, Navy, 1964-08-11 - used with meteorological rocket for tracking upper air wind currents.
3150848 Method of decoying a missile from its intended target, Samuel E Lager, 1964-09-29, - IR seeker decoy "mixture of a pyrophoric and an oxidizer together with a suitable inhibiter (vapor depressant) such ,as a polyglycol. "
3221875 Package comprising radar chaff, Elmer G Paquette, USAF, 1965-12-07 342/12; 102/357; 57/13; 102/505 - Bundle of metal coated glass fibers
3263563 Flare ignition device, Harvey J Brown, Lundy Electronics & Systems, 1966-08-02, 89/1.51; 102/342 - expendable package looks like 5x3x2".

3473472 Photoflash
                  cartridge, Billy R Bliss, Clarence W Gilliam, John E
                  Laswell, US Navy, 1969-10-21

3473472 Photoflash cartridge, Billy R Bliss, Clarence W Gilliam, John E Laswell, US Navy, 1969-10-21, 102/346 -

3494163 Automatic coiling apparatus, Edward M Wight, Tracor Aerospace Inc, 1970-02-10, 72/129; 72/196; 242/535.3; 72/146; 242/413.2 -
3500409 Means for packaging and dispensing chaff, Burns A Cash, USAF, 1970-03-10, 342/12; 102/386; 102/357 - cap is caught by air and pulls chaff out of weighted container.
3557698 Photoflash bomb, David Hart, Henry J Eppig, Garry Weingarten, US Army, App: 1953-01-28, (20 year delay) Pub: 1971-01-26, 102/336; 102/382 -
3566852 Spring-type end-weighted rope reel chaff dispenser, Ramon I Padron, USAF, 1971-03-02, 124/6; 124/7; 221/92 -
3648350 Method of forming coil packages of metal foil strips, Patrick E Cassidy, Philip S Lowell, Tracor Aerospace Inc, 1972-03-14, 29/423; 156/155; 156/191; 428/906 - 
3708563 Magazine for aerial dispenser and method of making same, P Sells, 1973-01-02, 264/46.5; 89/1.816; 264/46.7; 264/255; 89/1.59; 264/46.6; 264/46.9; 264/277 - maybe the start of the 5x3x2" box?
3715754 Tethered chaff strand countermeasure with trailing end kite, J Parry, USAF, 1973-02-06, 342/12 -  
3721196 Chaff dispensing system, E Willis, L Musser, J Seagraves, 1973-03-20
3730098 Apparatus for quick-blossoming chaff ejection, W Edwards, US Secretary of Navy, 1973-05-01
3797394 Chaff dispenser, method of dispersing chaff, J Thurston, G Adams, 1974-03-19
3910189 Deployment of conductors into the atmosphere, Roger W Whidden, Frank R Leonard, Sidney Rosenthal, Richard O Fitzpatrick, USAF, 1975-10-07, 102/351; 102/377; 342/12; 102/504 -
3965472 Off-resonant chaff system for a large target viewed by low frequency radar, James Nickolas Constant, 1976-06-22, -
4063485 Decoy launcher system, Huges, GD, 1977-12-20, - anti ship multiple launcher
4404912 Chaff cartridge for aircraft defense, Paul Sindermann, Diehl Stiftung and Co, 1983-09-20
4167009 Re-entry chaff, Walter Schwartz, McDonnell Douglas Corp, 1979-09-04 - long range ballistic missile

4171669 Decoy
                  flare, Navy, 1979-10-23

4171669 Decoy flare, Navy, 1979-10-23, 102/357; 102/342; 102/350 - "A decoy flare cartridge for use in an aircraft photoflash cartridge rack", electrical ignition,

"The expelled hydrocarbon compounds are then ignited to form an infrared source for decoying a hostile infrared seeking missile away from the tailpipe of the decoy-carrying aircraft."

Aerial cameras like the KA-45, KA-56, KS-87 (National Museum) can be used at night when a Photoflash cartridge is used to make a flash.  The M-112 (1 pound) or M-123 (4.3 piound) were common.  The LA-307A Ejector, NSN: 6760-00-015-1927 holds 10 of the M123 cartridges.  They appear to be much larger than today's flare/chaff cartridges.

Installation and Maintenance of Aerial Photographic Equipment, AF 95-3, 1964 (pdf) 449 pages - pg252:
Two types of cartridges are available. These are the M-112 and the M–123. The M-112 is ejected from the A-5 (50 cartridges) or A–6 (52 cartridges) cartridge ejector while the M–123 is ejected from the B-4 ejector (20 cartridges) [LA-307 holds 10 cartridges]. Selection of either cartridge is made by actuation of the MODE switch on the sensor control panel to NIGHT A or NIGHT B. The previous action will also switch the cameras and the photographic control unit to the night mode. The photographic control unit then routes the shutter trip pulses to the cartridge ejectors in the flare pod. The pulses are also used to operate the cartridge remaining counter and the count limit counter on the film cartridge exposure panel. When a predetermined number of cartridges has been expended, the cameras will automatically shut down. The clam-shell doors on the flare pod open and close automatically when the select buttons on the sensor control panel are actuated. The door position is monitored by a door-closed warning light on the door position indicator panel. For emergency opening, the EMERG OPEN switch on the same panel is actuated to apply pneu matic pressure to the door mechanism. Provision has also been made on this aircraft so that the entire flare pod can be jettisoned in case of an emergency.

Table 7-2 Characteristics of the M-112 and M-123A1 Cartridges

Total Weight
16.4 oz
4.3 lbs
Outer case weight
4.4 oz
1.3 lbs
Flash powder weight
7 oz
1.7 lbs
Muzzle velocity
130 f/s
70 f/s
Peak candlepower
110 million
265 million
1.2 million
6 million
Time to peak
3 mS
4 mS
Duration of flash
30 mS
40 mS
Fuze delay available and A/C used: RB-47E, RB-57A, RB-66, RF-84F

Some of the early nighttime aerial photography was done using strobe lights the high energy drive was used for the Fat Man atomic bomb.  See my web pages: Egerton, GR Strobotac, Sonar & Krytron
Also see: 
Harold "Doc" Edgerton - Nighttime Photography -
Wiki: Photoflash bomb -

Aerial photographic reconnaissance, AF 55-6, 1955, (pdf), 153 pages -
                            photographic reconnaissance, AF 55-6, 1955
Electrically triggered primer, not like small arms with firing pin.
The M-112 and/or T-89 photoflash cartridges look like precursors
to the modern round flare/chaff cartridges.

Evaluation of the XM-143 Photoflash Cartridge (DTIC_ADA030773), May 1951 - plastic: 1.48" dia x 6.20" long, Aluminum: 1.57" dia x 7.81" long.  Evaluated on the L20 blimp (Wiki) and AO-1 Fokker (Wiki).

Patent Citations (11)
Publication   numberPriority date  Publication date  Assignee  Title
US3150848A *  1961-06-28  1964-09-29  Samuel E Lager  Method of decoying a missile from its intended target - pufs of IR radiation from burning
US3243270A *  1960-06-01  1966-03-29  Continental Oil Co  Preparation of gelled liquids
US3439612A *  1966-11-14  1969-04-22  United Aircraft Corp  Hybrid flare -  hybrid rocket motors as the source of radiant energy
US3473472A *  1964-08-13  1969-10-21Us Navy  Photoflash cartridge
US3612857A *  1970-03-16  1971-10-12  Dave P Beatty  Location marker for producing luminous display
US3712224A *  1971-06-21  1973-01-23  Us Navy  Decoy flare with traveling ignition charge
US3736874A *  1970-05-28  1973-06-05  Us Navy  Chemiluminescent expulsion device
US3808940A *  1964-12-24  1974-05-07  Gen Dynamics Corp  Portable decoy launcher system and rounds therefor
US3841219A *  1964-08-12  1974-10-15  Gen Dynamics Corp  Decoy rounds for counter measures system
US3964393A *  1974-06-21  1976-06-22  The United States Of America As   Represented By The Secretary Of The NavyIgniter
DE2509539A1 *  1975-03-05  1976-12-23  Dynamit Nobel Ag  Single or multiple component ejector for artificial cloud - has generating materials ejected by compression for mixing to form cloud after ejection

Cited By (17)
Publication number  Priority date  Publication date  Assignee  Title
US4292208A *  1974-05-03  1981-09-29  Alloy Surfaces Company, Inc.  Diffusion coating combinations
US4349612A *  1978-11-24  1982-09-14  Alloy Surfaces Company, Inc.  Metal web
US4444111A *  1978-09-30  1984-04-24  Nico-Pyrotechnik Hanns-Juergen Diederichs Kg  Crowd control projectile and method of ejecting same
US4498392A *  1981-06-03  1985-02-12  Etienne Lacroix - Tous Artifices  Infrared decoy launching device to be deployed rapidly with a double safety device
US4646643A *  1984-08-03  1987-03-03  Proll Molding Co., Inc.  Cartridge assembly for a projectable load
US5092244A *  1984-07-11  1992-03-03  American Cyanamid Company  Radar- and infrared-detectable structural simulation decoy
US5129323A *  1991-05-24  1992-07-14  American Cyanamid Company  Radar-and infrared detectable structural simulation decoy
US5343794A *  1979-04-04  1994-09-06  The United States Of America As Represented By   The Secretary Of The NavyInfrared decoy method using polydimethylsiloxane fuel
US5565645A *  1995-04-24  1996-10-15  Thiokol Corporation  High-intensity infrared decoy flare
US5602362A *  1981-12-11   1997-02-11  Lacroix Soc E  Electromagnetic decoy with delayed ejection
US5619009A *  1995-01-31  1997-04-08  Princhim S.A.  Smoke bomb case
US6324955B1  1992-04-20  2001-12-04  Raytheon Company  Explosive countermeasure device
US20040011235A1 *  2000-12-13  2004-01-22  Callaway James Dominic  Infra-red emitting decoy flare
US6686866B1  2002-09-26  2004-02-03  The United States Of America As Represented By The Secretary Of The Navy  Two-piece radar-absorbing end cap assembly
US20050029394A1 *  2003-07-22  2005-02-10  Ackleson James E.  Conformal airliner defense (CAD) system
US7343861B1  2005-05-31  2008-03-18  The United States Of America As Represented By The Secretary Of The Navy  Device and method for producing an infrared emission at a given wavelength
US10001351B2 *  2014-03-03  2018-06-19  Etienne Lacroix Tous Artifices S.A.  Decoy cartridge for aircraft

4313379 Voltage-coded multiple payload cartridge, David W. Wallace, Tracor Aerospace Inc, 1982-02-02, 102/217 - uses Zener diode to allow polarity control of expendables
4371874 Chaff dipole elements and method of packaging, Richard L. Bloom, App: 1973-10-05, Pub: (10 Year Delay) 1983-02-01, 342/12 - use Al, Cu, Zn & Tin to get different fall rates
4597332 Chaff dispenser for atmospheric re-entry, Leonard M. Hoffman, John B. Kimball, App: 1964-12-03, (22 Year Delay)Pub: 1986-07-01, 102/505; 102/351 - for missile reentry
4646643 Cartridge assembly for a projectable load, Joseph M. Goldenberg, Proll Molding Co, 1987-03-03, - "Unitary cartridge of plastic material for discharging a pyrotechnic mixture, smoke flare, chaff round, and the like is disclosed."  Works with a "replaceable impulse cartridge".

4650092 Device for the ejection of boxes through the exit of a container and box adapted for use in such a device, Nils A. T. , Andersson, Bo S. Lindgren, U.S. Phillips Corp, 1987-03-17, 221/222; 221/226; 221/231; 414/797.7 - non jamming version of 2954948box dispenser. 
4763127 Fiber under foil chaff coil, Bradley T. Sallee, Armtec Countermeasures Co, Tracor Aerospace, 1988-08-09
6231002 System and method for defending a vehicle, Boeing Co, (Rockwell), 2001-05-15 - to protect the B-1 from missile attack using a hard body (“Killer Volleyball” or “KV”) that's powered by multiple rockets. - overview of prior art systems to protect aircraft from surface launched missiles.
6980152 Externally cued aircraft warning and defense, Textron Sys,
7363861 Pyrotechnic systems and associated methods, Neal W. Brune, Andrew R. Dawson, George H. Wessels, Kevin M. Ford, Armtec Defense Products Co, 2008-04-29, 102/342; 102/336; 102/341 -
7814820 Method and apparatus for manufacturing wad-less ammunition, Jay Menefee, Polywad Inc, 2010-10-19 - related to launching systems.
8612179 Systems and methods for operational verification of a missile approach warning system, DRS Sustainment Sys, 2013-12-17, source: 345 nm UV + IR laser- for triggering AAR-47 and AAR-57 MAWS.
20030137442 Anti-radar space-filling and/or multilevel chaff dispersers, Carles Baliarda, 2005-04-05, - uses fractal patterns

Radar Man: Ed Lovick (Wiki: A12)

2599944 Absorbent body for electromagnetic waves, Winfield W Salisbury, Navy, Filed : 1943-05-11, Pub: 1952-06-10 - book (Aircraft Ref 9) mentions Aquadag (Wiki)
also see Aircraft Ref 9 & Ref 13 
While learning about the U2 got the book: "Spyplane: The U-2 History Declassified", Norman Polmar, 2001 - and the prior owner was Ed Lovick who had added newspaper clippings and post-it notes related to stealth.
Amazon: Radar Man: A Personal History of Stealth 2010 by Ed Lovick.

Radar Cross-Section

RCS (Wiki) is a measure of how much energy comes back to a radar from some object at some frequency and involves polar diagrams in azimuth and elevation.
1960 Powers shot down by the SA-2 (Wiki).
Hewlett Packard introduced the 8410 Vector Network Analyzer in 1967.  So I studied AN77-1 also in 1967 and later AN95 on Scattering Parameters.
There was a government service that would allow me, at work, to search for white papers on various topics and so I searched for "Scattering Parameters".
What came back were a large number of papers on Radar Cross Section, but none about microwave testing.

In Russia during the cold war Petr Ufimtsev (Wiki) wrote a paper "Method of Edge Waves in the Physical Theory of Diffraction".  An English version is available online as AD733203.pdf, 7 Sep 1971.  Some important concepts are Geometrical Optics (Wiki, refraction, refraction, light is a ray, &Etc), Physical Optics (Wiki, light is a wave, Wiki: Dffraction).  The paper is all about diffraction and ways to calculate it.  This formed the basis of designing aircraft (and later ships &Etc) that have very low RCS. from Aircraft Ref 9
YouTube: The Evolution Of Stealth Technology -
Also see my Aircraft web page.

NDRC Div 14, Vol 1, RADAR: Summary Report and HARP Project, 1946 - Declassified from SECRET Sep 26, 1960. - HARP might mean High Absorption Radar Paint. 


Panoramic (Radio Corp or Labs or Products)

1917268 Multiple frequency receiving system, Carlos B Mirick, National Electric, App: 1930-04-11, 455/145; 342/443; 455/157.2; 324/76.41; 346/33B - motorized tuning

This is the start of panoramic receivers, pan adapters and spectrum analyzers.
Navy-Radio: Receiving Panoramic Adaptor (Panadaptor) Info -

RBU-1 0.4

RBV-1 0.4


RBW-2M 5.25




RCX 0.45-0.47

0.54 - 29 Mhz




A Panoramic adapter was an accessory to a receiver.  The early tube receivers had IF frequencies around 200 or 455 kHz and so the pan adapters used those IF frequencies as their input.  Later receivers used two IF frequencies.  The FM radio IF of 10.7 MHz was used on AM radios followed by the classic 455 kHz IF.  This allowed pan adapters with an input of 10.7 MHz to see a much wider spectrum than the early units which were limited to the IF bandwidth of the host radio.

To get even wider bandwidth pan adapters the IF was doubled (10.7 * 2 = 21.4 MHz).  The CEI TEMPEST receivers have 21.4 MHz outputs and the Spectrum Monitor uses 21.4 MHz inputs.

To get even wider bandwidth in pan adapters a new IF frequency of 300 plus 21.4 MHz = 321.4 MHz is used on some equipment.  Various components of the HP 70000 Modular Measurement System (MMS) make use of 21.4 and 321.4 MHz signals.

The Agilent E4404B 9 kHz to 6.7 GHz Spectrum Analyzer has a 21.4 MHz Aux IF output and has AM or FM demodulation of the tuned frequency.

There are a number of Optical Spectrum Analyzers that are functionally the same as these except they work at wavelengths of light.

The analog series of Spectrum Analyzers has a linkage between sweep speed and Resolution Bandwidth (see patent 2661419 below).  This coupling was broken with the development of DSP (Wiki) based Spectrum Analyzers where a very wide IF is digitized into In-phase and Quadature (I-and-Q) channels and digitally processed to determine the Resolution Bandwidth.  The HP 4395A is this type of Spectrum Analyzer and has a extremely fast sweep speed compared to analog SAs.  Another key difference is analog SAs use some from of Peak Detection, but the DSP type SA can compute the RMS magnitude of the signal and so can display noise as SQRT(RMS) directly.

Navy RBY-1
                  Spectrum Scope over Hallicrafters SX-28 receiver
(Wiki: Radio Spectrum Scope source for image at left).
Navy RBY-1 Spectrum Scope over
Hallicrafters SX-28  receiver (Wiki)

Panoramic Radio Products IP-173C/U

Photos courtesy of eBay seller: pcobra93
This is just the indicator. 
There's another box the same size that's the power supply.

                  Panoramic Display

Name Plate lists patents:
2279151 See below
2381940 See below
2502295 Double range panoramic radio receiver, Wallace Marcel, Panoramic Radio Corp, App: 1943-08-25, W.W. II, Pub : 1950-03-28, -
2704806 Panoramic devices, Wallace Marcel, App: 1946-04-19, Pub: 1955-03-22, -
2367907 Panoramic radio receiving system, Wallace Marcel, App: 1941-11-21, Pub: 1945-01-23, -
2465500 See below
2590809 Variable selectivity panoramic system, Wallace Marcel, 1952-03-25, -
2704808 Receiver indicators, Wallace Marcel, 1955-03-22, -
2378604 See below
2502294 Double sweep panoramic radio receiver, Wallace Marcel, App: 1943-08-19 Pub: 1950-03-28, -
2661419 Wide band spectrum analyzer, Ben H Tongue, Marcel Wallace, 1953-12-01, - classic relationship between scan rate and resolution bandwidth quantified for the first time for an analog spectrum analyzer?
                  Panoramic Display
                          IP-173C/U Panoramic Display PRP
                          IP-173C/U Panoramic Display

2273914 Radio navigation system, Wallace Marcel, Panoramic Radio Corp, 1942-02-24, 342/462; 310/350; 310/318; 361/298.1  -
2279151 Panoramic radio receiving system, Wallace Marcel, Panoramic Radio Corp, April 7, 1042, 342/455; 346/37; 334/20; 334/33; 455/148 - tubes, motors, CRT - the beginning of spectrum analysis. Cited by 29 patents -
2312203 Radio beacon and panoramic reception system, Wallace Marcel, Panoramic Labs, 1943-02-23, 342/414; 343/726; 455/145; 327/113; 327/131  - aircraft DF, tubes, CRT
2378604 Radio altimeter and panoramic reception system, Wallace Marcel, Panoramic Labs,App: 1940-09-21, (SECRET during W.W.II) Pub: 1945-06-19, 342/462; 346/37; 334/5; 334/80; 340/977; 342/455; 455/73; 455/145 - Radio beacons where Tx frequency is coded as the altitude of the Beacon Tx.
2381940 Method and apparatus for simultaneous aural and panoramic radio reception, Wallace Marcel, Horace G Miller, Panoramic Labs, App: 1941-07-17 (SECRET during W.W. II), Pub: 1945-08-14, 455/146; 346/37; 89/41.07; 455/200.1; 455/195.1 - Wobulator (Wiki mechanical vibrator to change capacitance (frequency). Fig 8 "synchronous vibrating condenser"
2445562 Panoramic receiving system, Cawein Madison, Robert W Sanders, Farnsworth Research Corp, App: 1943-02-25, Pub: 1948-07-20, 455/146; 455/147; 455/148 -
2465500 Multiband fixed frequency calibration panoramic radio receiver, Wallace Marcel, Horace G Miller, Panoramic Radio Corp, Priority: 1941-07-17 (SECRET during W.W.II), Pub: 1949-03-29, 455/146; 455/147; 324/76.26 -
2498954 Panoramic receiver with means for modifying signal pulses applied to indicators, Joseph I Heller,
Panoramic Radio Corp, 1950-02-28, 455/147 -
2760081 Sweep circuits for panoramic devices, William I L Wu, Panoramic Radio Products, 1956-08-21, -
2820961 Navigational system,
Wallace Marcel, Panoramic Radio Products, 1958-01-21, - PPI display in aircraft based on VOR (Wiki)
2831146 Panoramic system, William I L Wu, Schlessel Bernard,
Panoramic Radio Products, 1958-04-15, - 
2840701 Spectrum analyzers, Hurvitz Hyman,
Panoramic Radio Products, 1958-06-24, - 
2886796 Proximity indicator,
Wallace Marcel, Panoramic Radio Products, 1959-05-12, - aircraft Tx a signal (200 kHz @ sea level, 220 kHz @ 40,000') nearby aircraft can be detected.  Very early anti-collision system.
2892944 Signal generator, William I L Wu,
Panoramic Radio Products, 1959-06-30, - crystal controlled synthizer
2970469 Panoramic heterodyne synchronous component analyzer, Edward F Feldman,
Panoramic Radio Products, 1961-02-07, - vibration analysis of rotating machinery
2971152 Harmonic spectrum analyzer, Ranky Bela,
Panoramic Radio Products, 1961-02-07, - sort of a tracking generator except working at harmonic frequencies.
2983870 Multiple band spectrum analyzer, Wallace Marcel, Panoramic Radio Products, 1961-05-09, -
2979714 Radar recorders,
Wallace Marcel, Panoramic Radio Products,1961-04-11, - for recording PPI displays which have fast phosphors
2998568 Time frequency analyzer, Schlessel Bernard,
Panoramic Radio Products, 1961-08-29, - Sonogram (Wiki) or Modulation Domain (Keysight)
3047823 Tunable piezo-electric crystal,
Ranky Bela, Panoramic Radio Products, 1962-07-31, - for use in IF filter


1917268 Multiple frequency receiving system, Carlos B Mirick, National Elec Supply, 1933-07-11, 455/145; 342/443; 455/157.2; 324/76.41; 346/33B - Neon lamp lights on dial at position indicating frequency and sweeps by motor. Camera records dial and clock face.
2084760 System for radio spectrography, Harold H Beverage (Wiki), RCA, 1937-06-22,
455/148; 332/150; 324/76.14; 324/76.41; 324/76.19; 332/167 - for checking for over modulation of TV signals by looking at the sidebands
2150553 Multiwave band superheterodyne receiver, Winfield R Koch, RCA, 1939-03-14, 455/191.1; 334/59 -
Band switch changes IF center freq along with RF input band
550 - 1500
1500 - 4500
4500 - 13500

2513384 Aperiodic radio receiver, Hoffert William
                  J, Veatch James P, FCC Radio Intelligence Division
                  (RID), Feb 14, 194
2513384 Aperiodic radio receiver, Hoffert William J, Veatch James P, FCC Radio Intelligence Division (RID), Feb 14, 1947, 375/339 - since no wide band (500 kHz - 80 MHz) RF amplifiers existed then they used an RF detector on the input followed by audio amplification. - This is in reality a crystal video receiver since the input tube is acting as a "grid leak detector" (Wiki).  This circuit both rectifies the incoming RF and amplifies the detected audio/video signal.

The BFO operates at audio frequencies, turned On/Off by switch SW1.
1464322 Radio receiving method and apparatus - tuned
1593837 Radio signaling system - tuned RF amp then detector
1615636 Signaling system - infrasound made so it can be heard with LO (see PSR-1)
2127525 Radio receiving system - superheterodyne radio
2383126 Spaced wave keying - teletype mark and space signals each has it's own channel
2400133 Double modulation radio receiver - VHF receiver suitable for CW

2522551 Radar warning system, Williams Everard M, Oct 26, 1945, Sep 19, 1950, 342/20, 327/37, 327/20
                A method to make it easier to differentiate high pulse repetition rate signals (tracking radar) from slower rate search radar signals using vacuum tubes.
2586894 Radio receiver, Everard M Williams, Jr  Benjamin R Gardner, Sec of War, App: 1944-10-05 (SECRET?), Pub: 1952-02-26,
455/132; 455/145; 250/214R; 455/146 - "combination of a broad-band panoramic receiver used in combination with a narrow-band receiver that comprises both an oral or listening unit and a panoramic unit which are used together for analyzing signals."

2602883 Early warning detector, Edgar Koontz Clarence, Page Irving H, (Sec of the Army), Nov 17, 1942, Jul 8, 1952,
, 324/76.39, 375/224, 342/20, 327/20
                A variable inductor is in the input circuit that includes a RADAR antenna and is followed by a number of vacuum tubes.
                By calibrating in input tuning dial the input frequency can be determined and by means of the audio tone the pulse repetition rate.
                Can detect CW signals by using a switch in front of the crystal video detector (the method used in Fuzz Busters).
2642534 Multiple standard inversion frequency measuring system, Alfred K Robinson, William J Hoffert, 1953-06-16,
324/76.41 - to accuratly measure frequency of VHF signals (same inventor as Aperiodic receiver, see 2513384 above)
2658994 Panoramic frequency indicator, William H Huggins, Paul I Richards, Sec of War, App: 1945-12-10, Pub: 1953-11-10, 455/145 -
3465253 Pulsed and continuous wave electromagnetic signal detectors, Rittenbach Otto E (US Army), Feb 9, 1967, Sep 2, 1969,
                455/281, 342/20, 342/203, 455/337
                Two paths one for pulsed and one for CW signals.
3061795 Flip-flop varies frequency of blocking oscillator
3094663 Microwave signal checker for continuous wave radiations, Siegel Vernon H, Radatron Res & Dev Corp, Aug 3, 1962, Jun 18, 1963,
455/324, 455/226.1, 375/338, 455/130, 342/20, 343/767, 330/10, 455/347, 455/325
                Handheld device to detect CW radars like used for door openers and traffic lights.  (also see: RF-204)

3408574 Portable radar warning receiver, Oliver G Currlin, Charles J Schmidt (Maxson Electronics Corp), Oct 29, 1968, 343/703, 324/95, 342/20
                battery powered flashlight sized housing, log amp, uses what may be X-band waveguide
3500401 See above
3550008 Radio frequency carrier wave signal detector, James A Bright, Dec 22, 1970, 375/339, 455/351, 342/20, 455/334, D10/104.1
                X-Band police radar detector using 1N23 diode and solid state circuit.

3671964 Automatic radar detection device, Trochanowski Andrew J, Wicks Steven A (US Navy China Lake), Jun 20, 1972, 342/20
                Shipboard RWR for fast PRF (tracking radar).

3765336 Chaff bullet, Kulsik R, Us Navy, Oct 16, 1973, 102/505, 342/12 - many referring patents
4176468 Cockpit display simulator for electronic countermeasure training, William B. Marty, Jr. , CUBIC Corp, 1979-12-04

Portable radar-detecting receiver, Allan B. Hitterdal, Northrop Corporation, Jan 1, 1980, 342/20, 343/774 -
                wave guide input to crystal video receiver acts as a 9 GHz high pass filter

Microscan Receiver

Found this as Chapter 8 Microscan Receivers in Ref 1.

2954465 Signal translation apparatus utilizing dispersive networks and the like, e.g. for panoramic reception, amplitude-controlling frequency response, signal frequency gating,frequency-time domain conversion, etc., Warren D White, Cutler Hammer, 1960-09-27, 455/146; 327/113; 327/114; 333/166; 455/147; 324/76.27; 370/517 -

"This invention relates broadly to signal translation devices employing sweep frequency heterodyne circuits, and particularly to such circuits which are capable of receiving a number of different frequencies simultaneously and yet give adequate resolution therebetween. In one aspect, the invention is directed to radio monitoring receivers of the panoramic type capable of continuous coverage of a wide signal band, and yet displaying signals within that band separately according to their frequency. In another aspect, the invention is directed to circuits analogous to filters, in which the frequency response can be amplitude-controlled in the time domain. A monitoring receiver of special characteristics in which both aspects of the invention are combined in also provided. Many features of the invention, although particularly useful in connection with the foregoing, are capable of other applications."

1960 was before the widespread use of Digital Signal Processing (DSP) chips.  They came 10 years later (Wiki).

Cavity Backed Spiral Antennas

The lowest frequency occurs when the outside diameter of the spiral is a wavelength.
Also see patents at: CEI \ Orion Non-Linear Junction Evaluator

Vought Aeronautics Antenna Cavity Backed Spiral 218-27510-1 01-54-05080 #CCL362

This was sold at a very low price as "not working".  You can see black burn marks on it, so probably totally smoked or it's just silver oxide?

Manufactured for
Vought Aeronautics Division
Electronic Resources Inc. L.A. Calif
Antenna, Cavity Backed Spiral
Part No. 218-27510-1.  Type No. 01-54-05080
N00383-69-A-4201???S  Ser. No. CCL362

Max working antenna diameter: 2.25" = 57.15mm
half wave = circumference = PI * D = 179.5 mm
Full wavelength: 2 * Half = 359 mm
300m / 359 mm = 0.84 GHz
The upper frequency may be limited by the Type-N connector at 12 GHz.
A 14:1 bandwidth.

Fig 1
                    Aeronautics Antenna Cavity Backed Spiral 218-27510-1
Fig 2
                    Aeronautics Antenna Cavity Backed Spiral 218-27510-1
Fig 3
                    Aeronautics Antenna Cavity Backed Spiral 218-27510-1

AEL Model: ASO111AA Cavity Backed Spiral Antenna

When this came I was surprised by how small it was, hence the photos on a 10 Dollar bill.

Fig 1
AEL Model:
                  ASO111AA Cavity Backed Spiral Antenna
1-5/8" max spiral diameter. = 41.25mm
half wave = circumference = PI * D =129.6 mm
full wavelength = 259.2 mm
300 meters / 259.2 mm = 1.16 Ghz.

The upper frequency limit may be limited by the SMA
connector to 18 GHz.

A 15.5:1 bandwidth.
Fig 2
AEL Model:
                  ASO111AA Cavity Backed Spiral Antenna

2863145 Spiral slot
                  antenna, Edwin M Turner, Air Force, 1958-12-02

2863145 Spiral slot antenna, Edwin M Turner, Air Force, 1958-12-02, 343/767; 343/895; 343/732; 343/908 -
30 MHz to 15 GHz, Flush mounting for high speed aircraft. 
3131394 Spiral
                  antenna with spiral reflecting cavity, Myron S
                  Wheeler, Navy, App: 1962-01-22

3131394 Spiral antenna with spiral reflecting cavity, Myron S Wheeler, Navy, App: 1962-01-22, 343/895; 343/914 -
3381371 Method of
                  constructing lightweight antenna, Earl D Russell,
                  Lockheed Sanders, App: 1965-09-27

3381371 Method of constructing lightweight antenna, Earl D Russell, Lockheed Sanders, App: 1965-09-27, 29/600; 264/46.6; 264/272.11; 343/912; 427/125; 29/846; 264/46.9; 343/895; 427/58 -
3717877 Cavity
                  backed spiral antenna, A Hanninen, S Scanlon, Lockheed
                  Sanders, App: 1970-02-27

3717877 Cavity backed spiral antenna, A Hanninen, S Scanlon, Lockheed Sanders, App: 1970-02-27, 343/872; 343/895 -

5815122 Slot spiral antenna with integrated balun and feed, Michael W. Nurnberger, John L. Volakis, University of Michigan, 1998-09-29, - cites 23;
Also see: CEI \ Orion Non-Linear Junction Evaluator


Information Friend or Foe (Wiki: IFF). In war time the IFF sets are programmed so that they only transmit when a secret code is received so that they do not become beacons telling the enemy where they are.  An exception happened during the Cuban Missile Crisis and Vietnam, see: Lockheed EC-121 Warning Star - College Eye - QRC-248 IFF systems that worked with Russian IFF equipment (Ref 2)

This receive then transmit system uses a local oscillator that is offset 30 Mhz from the Tx and Rx frequencies which are 60 MHz apart.  This is done in the same frequency pair used for aircraft transponders (Wiki).  Uplink to aircraft is 1030 MHz and downlink from aircraft is 1090 MHz with the LO at 1060 MHz. 

See the APX-6 airborne IFF Transponder.

The Aeronautical Radio Navigation Service (ARNS) operates in the 960 - 1215 Mhz band.  In the U.S. the FAA manages the 960 - 1164 MHz portion of that band.  ADS-B (Wiki) operates these same two frequencies but there's an optional aircraft output at 978 Mhz available for general aviation aircraft flying in the U.S.  Plane tracking web sites, like FlightRadar24 make use of ADS-B signals.  They do this by placing a hardware box that contains a 1090 downlink receiver and a GPS receiver both connected to the internet and the headquarters facility in Germany that feeds to web service.

3945006 Radio frequency coding system, Claud E. Cleeton, Navy, App: 1952-04-04, SECRET, Pub: 1976-03-16, 342/45 - Claud worked on other IFF stuff.


I have a radar CRT which may be for the APG-40 RADAR that was used on the F-94C Starfire jet (Wiki).
This is just a place holder if I can find it.
It's maybe a 4" long persistence (yellow) CRT mounted in a black crinkle finished tube maybe a foot and a half long.  A woven metal shield dovers the cable that's maybe a couple of feet long with a large multi pin connector.

RADAR Guided Missile

While learning about the Spery Rand Electromagnetic Radiation Monitor I came across this patent for a "beam riding" type missile guidance system.  It would make sense that they would develop this since many of their radars and test systems involve high power microwave transmitters.

3230348 Missile guidance system, Jr Edmund B Hammond, Sperry Rand, App: 1951-09-01, Pub: 1966-01-18, -

4665401 Millimeter wave length guidance system, John T. Garrard, Jack E. Gregg, Robert S. Roeder, Sperry Corp, 1987-05-12, - 13 citations, 61 cites,

LASER Guided Missile

The guidance rear end of a Russian anti-tank missile showed up out of the Ukraine war and is on order.  Probably in the 9M117 Bastion family (Wiki).  100mm dia. (Ref. 23, Wiki: "...the target has to be tracked by laser sight all the time, and the system can not be reliably used on the move.")   From eBay seller AlehandrosOV.

Line Of Sight Beam Riding (LOSBR) 9M117

Since I'm not sure of the make/model of this missile tail section I'm calling it the LOSBR (Wiki)
The overall diameter if the fins were folded is 93mm, so calling it a 100mm diameter which supports the idea this is the 9M117.  NATO AT-10  (Global Security: AT-10)
Cat-UXO.com - AT-10 (9M117 Bastion) Missile - It is similar to the PRG-7 in that it uses a small explosive to launch out of the barrel then a rocket powers it.
Also see the Russian PTAB-2.5KO Cluster bomb from the same Ukrainian source.  Also packaged using thin aluminum sheets to reinforce the shipping box.

YouTube: KA-52 (Wiki) has countermeasures for infra-red and laser guided missiles, it appears to lack radar jamming


The tabs on the fold out wings face the rear and I'm guessing they fit inside the booster charge so when the booster falls away the wings pop out.  Also when the booster falls away the Arming plunger pops back arming the rocket.  There are two slip fit electrical contacts at about 4 and 6 O'clock in Fig 3 that probably have something to do with spinning up the gyro prior to firing.

Ref 24 Army-guide: Designation: 9K116-1 Bastion/AT-10 has a description.  Note the top photo shows the booster charge attached and it has the look and feel of the rear of an tank gun round.  This anti-tank missile is used on many variants of the T-55 tank (Wiki).  There is a 1.5 second delay from the fire command until the booster charge goes off to allow the gyro to spin up.  The pendulum is probably read just prior to firing to normalize the gyro.

Ref 25 The complex of controlled tank weapons 9K116-1 Bastion - 9K116 introduced in 1981, works with rifled tank barrels, rocket uses two oblique nozzles,"The wings, opened with the help of a special device, are placed at an angle to the longitudinal axis of the rocket and provide rotation during flight.".  This seems odd.  I would think a left-right-up-down reference frame would be used like the other LOSBR missiles.

Fig 1 Many Ukraine Stamps
Russian Line Of Sight
                  Beam Riding (LOSBR) Missile
Fig 2 There might be a gyroscope inside.
Russian Line Of Sight
                  Beam Riding (LOSBR) Missile
Fig 3 Tail end has small light and larger photo sensor.
The large diameter window is covered with a thin plastic film.
Also a plunger just above the large window.  Probably activated when the boost charge separates, i.e. On switch.
Note: no rocket nozzle at tail.
Russian Line Of Sight
                  Beam Riding (LOSBR) Missile
Fig 4 Pendulum rotates 360 deg.
There is an up-down-left-right reference frame.
Gyro? does not move.
Russian Line Of Sight
                  Beam Riding (LOSBR) Missile
Fig 5 Disassembly required 3" long security bits
Harbor Freight Item 68460 + some customization with
Russian Line Of Sight
                  Beam Riding (LOSBR) Missile
Fig 6 The pendulum and gyro is all one assembly, see Fig 8 below.
Many wires on the back of the On switch.
Russian Line Of Sight
                  Beam Riding (LOSBR) Missile
Fig 7 Four electrical terminals so maybe the IR sensor is a Position Sensitive Device (Wiki).
There may be a removable retaining ring?
Russian Line Of Sight
                  Beam Riding (LOSBR) Missile
Fig 8 Gyroscope & Pendulum in same assembly.
Russian Line Of Sight
                  Beam Riding (LOSBR) Missile


Early anti-tank missiles, like the Bazooka were not guided.  There are many ways that Command guidance (Wiki) of a missile can be done.  Anti-tank guided missile (Wiki)

Manual Command to Line Of Sight (Wiki: MCLOS) - The AZON is an example where an operator uses remote controls.  The problem is it takes a lot of skill and concentration and the missile needs to go slow enough for the operator to follow.  One of the problems with AZON and the immediate follow on systems was that it was almost impossible for the operator to see the falling bomb.  That was solved by putting a bright pyrotechnic flare on the back of the bomb in what looks like a one quart or 1 gallon paint can.

Semi-automatic command to line of sight  SACLOS (Wiki) In SACLOS, the operator must continually point a sighting device at the target while the missile is in flight. Electronics in the sighting device and/or the missile then guide it to the target. The most common form of guidance against ground targets such as tanks and bunkers.

Line Of Sight Beam Riding (Wiki: LOSBR) "... is a technique of directing a missile to its target by means of radar or a laser beam. The name refers to the way the missile flies down the guidance beam, which is aimed at the target. It is one of the simplest guidance systems and was widely used on early missile systems, however it had a number of disadvantages and is now found typically only in short-range roles." In modern use, laser beam riding is generally limited to short-range missiles, both anti-air and anti-tank. Examples include:
US: ADATS (Wiki, Designation-systems) vehicle mounted SAM, anti-tank - 152mm "...the missile is much more expensive than other anti-armour missiles. Therefore it is de facto used by Canada as a pure air-defense weapon."  "..The US Army found ADATS unsatisfactory..."
UK: Starstreak (Wiki) - MANPADS - 130mm
Sweeden: RBS 70 (Wiki) - MANPADS - 106mm dia
Brazil: MSS-1.2 (Wiki) - anti-tank -? dia
Russian: 9K121 Vikhr (Wiki) - AGM - 130mm
Russian: 9M119 Svir (Wiki) - vehicle fired anti-tank - 125mm
Russian: 9M133 Kornet (Wiki) - tripod/vehicle launched - 152mm dia.
Ukrainian: Skif - Stuhna-P  (Wiki) - tripod fired anti-tank - 130/150mm


Evolution of anti-tank guided missiles.

3366346 Remote missile command system, William B
                  Mcknight, Lonnie N Mcclusky, Nickolas J Mangus, Army,
                  1968-01-30, - TOW missile
3366346 Remote missile command system, William B Mcknight, Lonnie N Mcclusky, Nickolas J Mangus, Army, 1968-01-30, - TOW missile uses modulated IR beacon at missile tail.
A pair of wires (90) connects missile to controller.

Requires tracking until missile hits target, not fire and forget.

3698816 Laser guidance system, Milton Lutchansky, Bell Labs, 1972-10-17, -
3868883 Guidance system, James M Tucker,
                  McDonnell Douglas, 1975-03-04, - TOW
3868883 Guidance system, James M Tucker, McDonnell Douglas, 1975-03-04, - TOW (Wiki)

Thruster elements (100) are on the side of the missile.  The wire is on the back.
Light from the lights (50) pass through chopper wheel (54) and chopper black (56).

Requires tracking until missile hits target, not fire and forget.
4014482 Missile director, Andrew T. Esker, John
                  L. Manche, Robert M. Siler, McDonnell Douglas,
4014482 Missile director, Andrew T. Esker, John L. Manche, Robert M. Siler, McDonnell Douglas, 1977-03-29, -beam rider, controller uses low power and a zoom lens
Comment: patent 3868883 does not work over water.

This patent removes the requirement for the wires, but works in a manner very similar to TOW.

4247059 Light emitting diode beacons for command guidance missile track links, Jimmy R. Duke, Walter E. Miller, Jr., Dorwin L. Kilbourn, Nicholas J. Mangus, Jr., Robert L. Sitton, Walter F. Fountain, Army, 1981-01-27, -replaces light bulbs in TOW missile with LEDs.

4383662 Ideal trajectory shaping for anti-armor missiles via gimbal angle controller autopilot, Robert E. Alongi, Robert E. Yates, John P. Leonard, Army, App: 1978-03-13, Vietnam, Pub: 1983-05-17, -

4432511 Beam-rider guidance using two overlapping reticle discs, Kay C. Tong, Northrop Grumman, 1984-02-21, -uses two rotating discs modulating a single beam.

5280167 Very high angular resolution laser beam rider detector having a gated image intensifier and a video camera, Jacques Dubois, Minister of National Defence of Canada, 1994-01-18, - a laser warning receiver (LWR)

5259568 Command optics, Max Amon, Andre E. Masson, Rheinmetall Air Defence, 1993-11-09, - beam rider missile laser zoom (not on missile)

5427328 Laser beam rider guidance utilizing beam quadrature detection, Kay C. Tong, Richard F. Binns, Northrop Grumman, 1995-06-27, -single beam

10274288 Missile for use in a laser beam riding missile guidance system, Paddy Mallon, George MCCONNELL, Thales, 2019-04-30, - maybe Starstreak (Wiki) SACLOS - works as MANPAD as well as anti-tank beam rider.

RU2582308C1/en Method of firing missiles controlled by laser beam, and optical sight of missile guidance system,

Russian Anti-Tank Missiles

2023 January:  With hundreds of Russian tanks destroyed by small anti-tank missiles what are the prospects for the the German Leopard 2, UK and US Abrams M1A2 tanks?
If the seeker in a Semi-Automatic Command Line Of Sight (Wiki: SACLOS) system is a thermal IR type, then thermal IR countermeasures can defeat it.
There are also options for either a wire or radio link between the operator and missile.
Also there are fully automatic (Wiki: fire and forget, FaF) systems.

The 9M123 Khrizantema looks like a formidable weapon system.

(Wiki link)
Drakon na
Taifun na
MCLOS (Wiki)
3M6 Shmel AT-1
Wire (Wiki: SACLOS)
3M11 Falanga
9M17 Fleyta
AT-2 1964
9M14 Malyutka AT-3 1961
9M111 Fagot AT-4 1962
9M112 Kobra AT-8 1956
9M113 Konkurs AT-5 1974
9K114 Shturm AT-6 1979
9K115 Metis AT-13 1992
Thermal Optics
9K116-1 Bastion AT-10 1981
LOSBR (Wiki)
9K118 Sheksna AT-12 1981
9M119 Svir AT-11 1984
9M120 Ataka AT-9 1985
9K121 Vikhr AT-16 1985
9M123 Khrizantema AT-15 2005 FaF
Laser or RADAR
ACLOS (Wiki)
9M133 Kornet AT-14 1998
9M133M Kornet-M na
Hermes-A na
cruise: radio cmd
Terminal: semi-active laser

Laser Target Designator (Wiki)

So far the patents are about aligning the visible and IR beams.  Not the beam modulation, although a patent mentioned the gap between a double pulse as being important.  Laser designators and laser imagers are intertwined.

3698812 Multi-function telescope, Harry Nelson, Hughes (Raytheon), 1972-10-17, -
3992629 Telescope cluster, Arthur S. Chapman, Hughes (Raytheon), 1976-11-16, -
4091412 Target designation system, David J. Salonimer, Army, App: 1972-12-29, Vietnam, Pub: 1978-05-23, - "This invention is in the field of ground target designators for airborne vehicles." " This invention is a target designation system employing laser illumination of said target and an imaging detector for displaying an area including said target, with the laser illumination relfected from said target being visible on said detector."
3274608 Seismic profiler
3305633 Laser optical system, Navy, 1966-09-20, - sea floor, drum recorder
3380358 Range gated imaging system, GE, 1697-02-21, - IR pulsed laser & image orthicon tube.
3527949 Low energy,interference-free,pulsed signal transmitting and receiving device
3689156 Range gated image systems using pulsed illuminators
3696248 Laser tracking method and apparatus, Robert A Cunningham, John T Winkler, Martin Marietta, App: 1972-10-03, - Fig 3 CW Tracker uses UDT SPOT Four quadrant photo detector, Fig 4 Pulsed laser tracker w/RF Tx, Gimbal w/RF Rx, Fig 5 pulse laser control, Fig 6 normalizer.
3778007 Rod television-guided drone to perform reconnaissance and ordnance delivery, S Kearney, W Richardson, Navy, 1973-12-11, - TV & Laser
3813553 Laser transciever, Sidney Grossman, Army, 1974-05-28 - modification of a SLR camera to send and decode modulated laser beam. (for use by spies?)

Cited by:
4174177 False target warning system, Navy, 1979-11-13
4269121 Semi-active optical fuzing, Navy, 1981-05-26
4497065 Target recognition system enhanced by active signature measurements, Westinghouse
4530600 Variable attenuator for optical transceiver, Northrop,
4638508 Portable FLIR beacon, Navy,
4737028 Target loop active boresighting device, Army
4786966 Head mounted video display and remote camera system, Varo
4884137 Head mounted video display and remote camera system, Varo
4947044 Method and apparatus for covertly viewing a target using infrared radiation, Boeing,
4970589 Head mounted video display and remote camera system, Varo
5005213 Head mounted video display and remote camera system, Varo
5200827 Head mounted video display and remote camera system, Varo
5291263 Laser range finder using a nonlinear crystal, Korea AIoSaT,
5329347 Multifunction coaxial objective system for a rangefinder, Varo,
5485012 Method and apparatus for blind optical augmentation, Army,
5786889 Method of monitoring coalignment of a sighting or surveillance sensor suite, Pilkington,
5898484 Hand-held distance-measurement device with an enhanced viewfinder, Harris
5933224 Hand-held distance-measurement apparatus and system, Hines
WO1999043016 Multi-function observation, ranging, and sighting device, Litton,
20030193980 Device and method for invisible road illumination and imaging using preliminary pulses, Oleg Matveev,
6650277 Target designation system, Navy,
20030230705 Active night vision system for vehicles employing anti-blinding scheme, Ford,
20040031922 Active night vision system for vehicles employing anti-blinding scheme, Ford,
6762710 Target designation system, Navy,
20050001756 Target designation system, Wilkinson James
20050134440 Method and system for detecting objects external to a vehicle,
2006086527 Radiation homing tag, BAE Systems, Intelligent Technolgies
2008071866 Method and device for detecting an object that can retroreflect light, Compagnie Industrielle
2010080189 Absolute time encoded semi-active laser designation, Raytheon
20100261145 A system and a method for transmission of information, Saab Ab
20100327105 Optical system for a missile, and method for imaging an object, Diehl Bgt Defence
WO2012000216 Binoculars with laser supplementary lighting, 西安华科光电有限公司,
8224189 Retro-directive target for free-space optical communication and method of producing the same, Sunlight Photonics
FR3007161 Method for Implementing a Simulation Test of a Real Situation Comprising a Generation of Different Vitrual Contexts, Cassidian
20140374533 Harmonic shuttered seeker, Rosemount Aerospace
EP2843355 Semi-active laser seeker synchronization, Rosemount Aerospace
GB2526506 Covert marking apparatus, Qinetiq Ltd
EP2993889 Illumination apparatus, Nxp B.V.
FR3040848 Method and Sstem for Bistatic Imaging, Sagem Defense,

4349838 Laser target designator system, Jean P. Daniel, Thales, 1982-09-14, -
5007736 System for target designation by laser, Jean-Pierre Daniel, Jean-Pierre Fauchard, Thales (Thompson CSF), 1991-04-16, - cites 9 patents, cited by 14 patents,
5114227 Laser targeting system, William C. Cleveland, Jr., Loral Aerospace, 1992-05-19, -
4315609 Target locating and missile guidance system, James D. McLean, Frederick C. Alpers, George R. Lanning, Fred H. Camphausen, Navy, 1982-02-16, - precision target location (20 - 30' CEP)
4093153 Ground-controlled guided-missile system, Manuel L. Bardash, Carl P. Clasen, Robert M. Scudder, Lawrence H. Simon, Charles S. Sorkin, Raphael O. Yavne, Robert W. Ekis, Alfred I. Mintzer, Army, 1978-06-06, - four (N, S, E, W) phased array radars allow air defense system to attack many simultaneous targets.
4279036 Secure (laser) communication system, Charles E. Pfund, 1981-07-14, -
3217097 Tethered hovering platform for aerial surveillance, Fritz K Pauli, Rudolf H Schlidt, 1965-11-09, -
3715953 Aerial surveillance and fire-control system, W Allan, Army, 1973-02-13, - similar to 3217097
4267562 Method of autonomous target acquisition, Peter K. Raimondi, Army, 1981-05-12, - TV camera in illumination flare package (w/parachute) uses image recognition to track targets. Some image recognition article references
6666142 Switch key tool for use in changing switch knob settings on a laser guided bomb, John Gregory Pearce, Gregory V. Brodbeck, Dept of Navy, 2003-12-23, - "Each guided control unit or computer control group has a plurality of Pulse Repetition Frequency (PRF) Code Switch knobs which are used to Set the pulse repetition frequency for the Laser Guided Bomb." Switch 30: 5,6, or 7; next two switches: 1 to 8; Weapon Type Switch: 8, 7, 6, 5,4, Skip 2, Skip 1, STD LGB.
6926227 Extended range, light weight laser target designator, Donald S. Young, Victor A. Misek, Lockheed Martin, 2005-08-09, - double pulse
8139205 Optical payload with integrated laser rangefinder and target designator, Stephen V. McKaughan, Philip A. Rombult, Robert J. Campbell, JR., Teledyne Flir, 2012-02-16, - FLIR.com pod/ball system

6626396 Method and system for active laser imagery guidance of intercepting missiles, Arnon Secker, Rafael Advanced Defense Systems, 2003-09-30, - active terminal guidance
20060232761 Laser designator for sensor-fuzed munition and method of operation thereof, Richard McConville, David Delude, Textron Systems, 2008-10-14, -
20090228159 Dual fov imaging semi-active laser system, Edward Max FlowersLionel D. LiebmanGregory N. WhitfieldArthur S. Bornowski, Lockheed Martin, 2011-11-01, -

Laser Warning Receiver

5260563 Compact laser warning receiver, Reginald W. Hunter, Gerald D. Powell, Ronald E. Ham, Joseph Lenhardt, Thomas G. Ratliff, Tracor Inc, 1993-11-09, -
FR2741449A1/en DETECTOR OF DIFFUSED RADIATION, Paul William Walland, Plessey Overseas, 1997-05-23, -
Laser Warning Receiver by Jin Mei, 1996 (ADA315183_text.pdf)

Wavelength um
0.69, 1.06
1.54, 10.6
0.9, 10.6
Range km
5 ~ 20
Diverangence mrad
0.5 ~ 2
0.2 ~ 0.5
8m dia
Pk Pwr W
106 ~ 107
106 ~ 107 10
Pulse width ns
10 ~ 20
10 ~ 20 >=105
Rep Freq Hz
0.1 ~ 20
10 ~ 20 103 ~ 105
Pulse coded
PCM, Pattern, Polarization

Non Imaging
Simple Low False Alarm rate
Large Field of View Large Field of View
Low Cost High Angular res

Fabuli-Puluo Maikeersun
single tube det
lo false alarm rate
lo false alarm rate
no mech scan
Wavelength output
captures short pulse

hi angular resolution

no need for direct interception of beam,
single tube detectors,
fixed view monitor
Low angular res
high cost
No wavelength output
No wavelength output
Hi False Alarm rate
needs narrow band filters

Mech scanning
small FOV
Missis short pulses
Hi Cost
Small FOV

Difficult to machine,
needs narrow filters,
no Direction output

GBPPR - Battlefield Laser Warning Receiver -


Ref 1  Microwave Receivers with Electronic Warfare Applications, Tsui, 1992, ISBN: 0-89464-724-5 -
Ref 2 The Strategy of Electromagnetic Conflict (ADA065453.pdf) by Richard E. Fitts, Feb 1979, 286 pages, 156 MB, 119 figures -

1. electronic Warfare
2. The Primary Electromagnetic Threats
3. Basic Concepts of the Electromagnetic Conflict
4. Electronic Reconnaissance
5. Electronic Countermeasures
6. Electronic Counter-Countermeasures
7. Communications
8. Future Regions of the Electromagnetic Conflict
9. The Electromagnetic Conflict in Space
10. Further Study on the Electromagnetic Conflict
Appendix A to F
Ref 3. 12 Seconds of Silence: How a team of inventors, tinkers, and spies took down a Nazi superweapon, Jamie Holmes, 2020 -
Proximity Fuze (Wiki, China Lake Patents, Radiosonde),
V-1 Vengeance Weapon 1 (Wiki),
Merle Tuve (Wiki) - while working with DTM (Carnegie) or at the NRL (Wiki)  was involved in the HF propagation experiments over the Potomac River where they had frequently stop because a plane was taking off or landing at Bolling Field (Wiki)
2931897 See Radiosonde patents by Van Allen
3166015  See China Lake Patents
Oslo Report (Wiki),
R. V. Jones (Wiki),
Vannevar Bush (Wiki, see Alfred L. Loomis & Tuxedo Park)
Patents by Vannevar Bush
1048649 Profile-tracer - machine shop measuring tool
1342250 Transformer - wireless signaling, probably long wave
1389026 Radio receiving system, American Radio & Research - for receiving CW so contains a vibrator type LO.
1452064 Radio transmitter, American Radio & Research - Damped oscillation
1617178 Electrical apparatus, Raytheon, - HV rectifier Helium gas, carbon electrodes,
1617179 Electrical apparatus, Charles G Smith, Raytheon, - HV rectifier
1617180 Electrical apparatus, Raytheon, - HV rectifier
1617181 Electrical apparatus, Raytheon, - HV rectifier
1709427 Electrical condenser, Raytheon, - pancake (HV?) liquid filled
1756481 Thermionic tube, Powel Crosley Jr, - Multiple plate/phase tube rectifier/detector
1846307 Refrigeration, Cambridge Labs, - e hermetically sealed
1859580 Valve, Spencer Thermostat, - toilet ball float valve that's quiet
1870235 Thermostat, General Plate Co, - pipe inline installation, uses a sheet of material
1880014 Gaseous conduction device
1883251 Thermostat
1897236 Signaling System Raytheon, App: 1928-11-06 - mechanical scan TV (Wiki)
1908316 Rectifying apparatus
1912358 Apparatus for establishing an artificial datum, - for a sextant
1925300 Electron discharge device, Raytheon, rectifier efficient at 300V 0.1A
1939875 Cable - adds compressible material so that the differential expansion coefficients of lead and oil are no longer a problem.
1947249 Telephonic telegraphy, - modem to send TTY over phone line
1960694 Temperature Control Apparatus
2032253 Amplifying system, Raytheon, - AC on filaments and backed out using transformers
2076977 Lubricating system for vehicle wheel bearings
2127286 Apparatus for transferring heat
2134273 Electrical condenser
2157229 Apparatus for compressing gases, Research Corp, - "city by a member rotated by mechanical power. In my compressor the volume is constant but the gas is alternately heated and cooled, producing corresponding changes in the (p) value (p) being the pressure, and v the specific (volume), and this change in value is used directly to produce the transfer of gas from a region of relatively low pressure to a region of relatively high pressure." Aimed at liquefying ga.
2175376 Method of and apparatus for converting heat
2319206 Machine for rifling guns, Sec of War, - for a barrel that squeezes the projectile
2379862 Justifying typewriter
2397467 Apparatus for generating continuously variable mechanical operations
2461032 Thermal apparatus for compressing gases
2749869 Pressure bulb control mechanism for hydrofoil craft
2873912 Electronic comparator, Sec of Navy, - mechanical, photocells, Thyratrons (Wiki), 70mm wide punched paper tape, 
2983098 Gas lubricated free piston engines with supercharging arrangements
3005306 Free piston engine power unit
3034945 Process of forming a sheet from glass fragments and plastic
3141437 Constant lift system for craft
3145660 Free piston hydraulic pump
3146765 Free piston engine
3183907 Device for inhalation aerosol
3199460  Hydraulic pump or motor
3211105 Hydraulic pump or motor
3211106 Hydraulic pump or motor
3211107 Hydraulic pump or motor
3270699 Hydrofoil craft
3242870 Hydraulic pump or motor
3457722 Hot gas engines method and apparatus - Stirling cycle engines
3527049 Compound Stirling cycle engines
3675738 Engine sealing - Stirling high temp
4250953 Piston sealing, MIT - Stirling ceramic coated pistons for high temperatures
4389921 Expansible chamber apparatus and its operation, MIT - Stirling ceramic coated pistons for high temperatures
C-SPAN: World War II "Smart Weapons" by Jamie Holmes, 54:55 - Feb 9, 2021
Ref 4. Quora: How were B-52s expected to get through Soviet air defenses to their targets?

Ref 5. Quora: How were B-52s expected to get through Soviet air defenses to their targets? Steve Heckman - plus many comments
Ref 6. Warriors and Wizards: The Development and Defeat of Radio-Controlled Glide Bombs of the Third Reich, Martin J. Bollinger, 2011 - Use of wire recorder to capture the control signals. Howard Lorenzen (Patents)
2620470 Doppler traffic control system, Jr Roy L Rather, Howard O Lorenzen, 1952-12-02, - CW Doppler seems like a poor idea since it can not see stopped cars.
2763783 High frequency oscillator, Howard O Lorenzen, App: 1946-04-05, W.W.II, Pub: 1956-09-18, - for use with Lighthouse tube (YouTube: Radar History: Part II: The Lighthouse Tube) Rudolph Dehn (Patents), William Kornrumpf (Patents),
Ref 7. Steve Blank - Secret History -list of reference books and web pages (also see his other talks above).
Ref 8. The Story Behind the Secret History Part II. Getting B-52s through the Soviet Air Defense System
B-52: ALR-20, ALR-117

Ref 9. IMINT & Analysis- includes SAM sites
Ref 10. First In, Last Out: Stories by The Wild Weasels - The Society Of Wild Weasels (Book & Movie)
Ref 11. Threat Warning for Tactical Aircraft: A Technical History of the Evolution from Analog to Digital Systems - Bjorn M. Fjallstam
Ref 12. The Cold War and American Science: The Military-Industrial-Academic Complex at MIT and Stanford - Stuart W. Leslie
Ref 13. Red SAM: The SA-2 Guideline Anti-Aircraft Missile (New Vanguard) - Steven Zaloga
Ref 14. Instruments Of Darkness The History Of Electronic Warfare, 1939 1945 (on line)
Ref 15. National Intelligence Estimate, Number 11-3-17 Soviet Strategic Air and Missile Defenses 9 Nov 1967
Ref 16. Russian SAMs and ABMs
Ref 17. Patterns and Predictability: The Soviet Evaluation of Operation Linebacker II by Dana Drenkowski & Lester W. Grau -
Shrike Air to Ground Missiles (AGM) are mentioned.
"Operation Iraqi Freedom where precision strikes destroyed key targets but left so little collateral damage that “shock and awe” did neither."
Ref 18. The Hunter Killers: The Extraordinary Story of the First Wild Weasels, the Band of Maverick Aviators who Flew the Most Dangerous Missions of the Vietnam War, Dan Hampton,2015
Ref 19. War in the Forth Dimension; US Electronic Warfare, from the Vietnam War to the Present, Dr. Alfred Price, 2001 - Contains a lot of information that I did not know.  But mentions the RWR items on this web page.  "If the Fan Song ceased transmitting at that point the Shrike was deprived of homing signals and "went stupid".  While this is correct the problem was the bang-bang control system where the control fins (mounted at the center of mass) would be either translating the missile left or right and up or down.  When the target signal stopped the fins did not return to the no movement position, but instead stayed where the last command put them, so it really was "stupid".
National Electronics Museum - Library & Archives - exhibit relating to chaff, but nothing on line.
Ref 20. Flying Colors by Sarah Moore, 2015 - see YouTube: BookTrib Interview With Sarah Moore, Author of 'Flying Colors' - a biography of Victor Tatelman
Ref 21. Hangar Thirteen (B-17F); Library: Army Air Forces, Graphic Survey of Radio and Radar Equipment, 1 Feb 1945, 89 pgs
Ref 22. Ukrainian MiG-29 Fulcrums fire AGM-88 anti-radiation missiles at Russian positions - BSU-60 A/B Mfr: 96214 (D) YouTube, 0:22 -
Ref 23. A Brief Introduction to the Evolution of Soviet/Russian Anti-Tank Missiles (Photos) - In Chinese, but Google translate works.
Ref 24. Army-guide: Designation: 9K116-1 Bastion/AT-10 -
Ref 25. Topwar.ru: The complex of controlled tank weapons 9K116-1 Bastion -
Ref 26. Designation-Systems.Net:
Ref 27. How This Tiny Truck Took Down an Army, 21:19 - Wiki: Technicals, (Wiki: Battle of Fada) -
Ref 28. The Toyota War | Type 1 Technical (Toyota Land Cruiser 70 Series) Part 1, 35:14 - While not mentioned in Ref 27 & Ref 28, the PRG-7 played an important role.
Ref 29.
Ukraine's Air Defense-hunting missiles are about to get a LOT better, 4:59 - HARM Soviet block v. US aircraft
Ref 30.  see RDF Ref 19: RDF to RADAR | The secret electronic battle (1946)
Ref 31. 'Window' (Radar Chaff): WWII's Secret Weapon, 27:01 -
Ref 32. Millennium 7 * HistoryTech: This was an Unexpected Discovery, 12:14 - Pen Aids, 9M723K1 Iskander
Ref 33The Invisible War in Ukraine Being Fought Over Radio Waves: Using electromagnetic waves to flummox and follow smarter weapons has become a critical part of the cat-and-mouse game between Ukraine and Russia. The United States, China and others have taken note. 2023 Nov 19 -
Ref 34. Electronic Warfare: The Invisible Battlefield, 19:03 - SIGINT (Wiki) =  ELINT + COMINT
Ref 35. Radar Sensors / Switches: Comparison and Tests, 16:10, 2020 -
Ref 36. Radar Sensors from $3 to over $100: Which one is Best?, 14:30, 2023 - FMCW Wiki -
Ref 37. How microwave body detectors work. With RF section schematic, 30:17 - 


Wings Over Vietnam - Wild Weasels Documentary (46:47) -
"First In - Last Out" relates to the relative speed of the F-100 (Wiki) and F-105 (Wiki).
The function of the Shrike missile was to destroy the SA-2 RADAR antenna.  The site could also be destroyed using cluster bombs.
May 1968 - Introduction of AGM-78 Standard anti-radiation Missile (Wiki).
Wings Over Vietnam - Spookies, Spectres and Shadows Documentary - Gun Ships
Wings Over Vietnam - The Mission The (helicopter) Gunships -
Not What You Think: Why Russia is INCAPABLE of Air Superiority in Ukraine, 13:37, -
Ward Carroll:
Land-Based Navy Jammers Moved to NATO's Eastern Flank, 7:06 - Deep Intel on Russia's Air Ops Against Ukraine, 51:53 - with Justin Bronk

My Related web pages

An Instantaneous Direct-reading Radiogoniometer by Robert Watson-Watt, 1926
China Lake Patents
SkyScan Severe Thunderstorm Detector - displays rough range to lightening
Military Vehicles
Radio Direction Finders
Range Finders
Altimeters & Barometers
RPG-7 Rocket Propelled Grenade Launcher 
Infrared - Meon FLTS EU00001-02-FG Infrared & UV Test Set (related to AAR series equipment -


YouTube: Millennium 7 * HistoryTech: Videos - Playlists -
AFCEA -Armed Forces Communication and Electronics Association
APR-25-  F100 nose antenna - another shot of nose antenna
Association of Old Crows - was a member for a couple of dozen years
Boeing - Wild Weasel - F-4 Phantom
Desert Storm - The Electronic Battle - Part 2 - Part 3 - many of the systems were Vietnam vintage
Society of Wild Weasels -
Republic F-105G Thunderchief -
Necessity is the mother of invention, and the need to counter North Vietnam's SAMs brought forth the Wild Weasel. by John D. Cugini
Air Force - F-4G Wild Weasel -
Association of Old Crows - Gold Crows (SF, CA) - Operation Desert Storm: EW Lessons Learned -
McDonnell Douglas F-4G Wild Weasel -
F110F Wild Weasel - scale model ALR-25
FAS - F-4 Phantom II, F-4G Advanced Wild Weasel -
Air Force Association - Wild, Wild Weasel - Foal Eagle '97: Wild Weasels bring 'hurt to the bad guys'  -
Air Power Over Vietnam - North Vietnam's Air Defenses -
McDonnell EF-4C Phantom II -
AWST - Kosovo Signals EW Weaknesses -
WCS Info - Weapons Control Systems
Aircraft Survivability Newsletter -
Litton Amecom - Electronic Combat - The Applied Technology Inc. was bought by Litton and is now the Applied Technology division in San Jose
Designations Of U.S. Military Electronic And Communications Equipment - AN/ALR - Airborne Countermeasures Receivers by Andreas Parsch
Fi-103/V-1 "Buzz Bomb" During WWII electronic counter measures were used to reduce the damage caused by the V-1
[7.0] Anti-Radar Missiles by Greg Gobel
Historical Electronics Museum - some AOC type exhibits
Shipboard Radio Room 4 - an RWR system fitted on a ship AN/UPD 501 Radar D/F Receiver
F-4G Desert Storm - SSgt John Burke (front seat), SSgt Fran?? (rear seat) *** tail: WW 273, WW 231, WW 303, WW 265
Air Force and Navy Radar Warning Receiver Programs - Merging Navy ALR-67 and AF ALR-69 into joint ALR-74 did not work.  T-NSIAD-87-31: Published: Apr 28, 1987. Publicly Released: Apr 28, 1987.
Pasternack Radar Demonstration Kit - probably based on the MIT: Build a Small Radar System Capable of Sensing Range, Doppler, and Synthetic Aperture Radar Imaging
DEFCON 19: Build your own Radar - The same RADAR as the above link.
A History of U.S. Navy Periscope Detection Radar: Sensor Design and Development, Shannon, Moser, Rite-Solutions, N00178-04-D-4115, 31 Dec 2014. - info on German u-boat RWR equipment development in light of the changing frequencies of British surface search radars.
Robert Morris Page (Wiki; Patents) - Over The Horizon RADAR (Wiki) - Monopulse RADAR (Wiki) 2929056 - IFF (Wiki; patent No.:254109233119123296615)
SR-71 Pilot Interview Richard Graham Veteran Tales - started out in Wild Weasel (Wiki) - also SR-71 cockpit & engine
The Navigator (801 pages) Vol 7 No. 1 January 1961 "The Wizzard" pg 2 by Capt. William C. Luce, Capt. Robert B. Stewart, Keesler T.T.C Air Training Command -  the first 43 pages are all EW related.
Curious Droid: The Wild Weasels - When Electronic Warfare Became Real, 16:13 -
The War Zone: The Time A F-4G Wild Weasel's Anti-Radiation Missile Blew Apart A B-52's Tail: The freak friendly fire incident during Desert Storm that was almost fatal for a B-52 crew:
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Page created 6 Jan 2001.

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