Sonobuoy Based Outdoor Intrusion Detectors

Background

Sonobuoys

Sonobuoys (Wiki) have been around since about May 1941 when P. M. S. Blackett, head of the British Admiralty committee for antisubmarine measures, proposed the idea.  In June 1942, the AN/CRT-1 became the first operational sonobuoy which was launched from a ship in a convoy, and on July 25, 1942, the first successful launch of a sonobuoy from an aircraft was made from a U.S. Army B-18 bomber (Wiki). (from: Not Ready for Retirement: The Sonobuoy Approaches Age 65 by Holler, Roger, Horbach, Arthur, McEachern, James).

  They are nomenclatured SSQ-nn.  They are a part of anti-submarine warfare (Wiki).

"All sonobuoys currently in inventory are normally launched from standard A-size tubes via pneumatic, free fall, or a Cartridge Actuated Device (CAD).  Shipboard personnel may also launch them by hand or Over the Side (OTS). All are powered by either salt water activated magnesium or silver chloride, lithium chemistry, or thermal batteries and are designed to scuttle at some point after usable or selected life expires."  from Approved Navy Training System Plan, for the Consolidated Sonobuoys.  N88-NTSP-A-50-8910B/A SEPTEMBER 1998

There's a problem with airborne sonobuoy receivers being used with MAD.   MAD works best when the plane is flying at about 500 feet.  This is also true for the periscope detecting RADAR.  BUT . . . .
The sonobuoy receiver will have relativity short rang when the plane is at 500 feet.  Much higher would allow better sonobuoy coverage.  Not sure what's an optimum altitude for dropping sonobuoys.   The new Navy P-8 (Wiki) no longer uses MAD and flies much higher, both for more sonobuoy area coverage and for better fuel consumption than it gets when flying low.  The P-8 has the AN/APY-10 RADAR (Wiki) but as far as I can tell it doe not work as well at high altitudes because the ocean surface scatter gets poorer at higher altitudes.  The poorest result is looking straight down on the water.

CNU-239/E Shipping Tube 

This may be the standard shipping container for A size sonobuoys.  It's 45" long and an octagon 6-3/4" across the flats.  One end unscrews and when shipping the cap is tapped to the main body.  The weight depends on what model in inside.

Transport Canada SU 0850 makes provision for shipping experimental sonobuoys in this container. But there are limitations: (a) all the dangerous goods are contained within the aluminum body of the experimental sonobuoy described by drawings no. 200896, 200898, 200702, 200671, 200836 and 200837 deposited by Ultra Electronics Maritime Systems, a division of Ultra Electronics Canada Defense Inc. on Transport Canada's Transport Dangerous Goods Directorate file A 4069-0850; (b) the sonobuoy contains a single UN0454 Igniter having a net explosive quantity equal to or less than 0.15 g; (c) the sonobuoy contains a maximum of 2 cylinders of UN1013, Carbon dioxide, each having a capacity equal to or less than 0.120 L; (d) the sonobuoy contains a quantity equal to or less than 40 "C" size lithium batteries that meet the requirement of paragraph (1) of Special Provision 34 of Schedule 2 of the Transportation of Dangerous Goods Regulations; (e) the sonobuoy is packaged in the military performance specification plastic shipping container type CNU-239/E specified in the drawing 012-159-0009-00 deposited by Ultra Electronics Maritime Systems, a division of Ultra Electronics Canada Defence Inc. on Transport Canada's Transport Dangerous Goods Directorate file A 4069-0850;

A Size

Modern sonobuoys have an outside diameter of 4-7/8" (fit 4-15/16" launch tube commonly called 5 inch) and are 1 yard long (36").  The max weight is 39 pounds. 
This is a convenient size for one man to handle on a P-3 aircraft (Wiki).  The larger sizes are not easy to handle.  There are smaller sizes based on getting some integer number of them inside the A size outline.  3 each is called "F" and 2 each is called "G".  The other sizes are pretty much not used in volume.

Hydrophone

A hydrophone (Wiki) is the common sensor for sonobuoys and is typically deployed at 20 meters (65 feet: shallow) or 120 meters ( 328 feet: deep).  A sonobuoy might have 50 depth settings that can be set prior to ejecting it from an aircraft.  This is important because of what's called the thermocline (Wiki) which is where the temperature of the water changes rapidly.  This changes the speed of sound (Wiki).  This causes the sound to change direction just as light will be bent by a change in refractive index (Wiki).  And just like light there's conditions where the bending acts like a mirror and all the sound (or light) is reflected off the layer instead of just changing angles.  So if the hydrophone is on the wrong side of the thermocline it may not hear a sub that's on the other side.

Bathythermograph (Wiki: BT)

This is a device that measures the water temperature as a function of depth.  For example the SSQ-36 might first be dropped and the temperature profile recorded.  Then the ideal depth for the hydrophone determined and programmed into the sonobuoy.  Then the sonobuoys would be dropped.

The speed of sound in water depends on temperature so it slows down as the depth moves from the warm surface to deeper depths, but at some point the pressure caused by depth will cause it to speed up again.

Service Life

The service life can also be programmed prior to launch for 1, 3 or 8 hours.  After that time the sonobuoy will sink to the bottom.

Radio Transmitter

A VHF vertical whip antenna is used.  One feature of this type of antenna is that there's a null directly above the buoy so when an aircraft directly overflys the buoy there's a characteristic signal drop out.  This allows confirming the buoy location.  The 1 Watt transmitter is FM modulated and covers an audio bandwidth of 10 Hz to 20 kHz (about the same as a Hi-Fi system or entertainment FM radio).  Note that there is no provision to hear the 37 kHz ping made by Cockpit Voice Recorders or Flight Data Recorders.  The FAA and Navy need to coordinate this.

Sonobuoy Radio Channels

See the VHF part of the Frequency Assignment table for some common ways the spectrum is used.  For example, FM broadcast band is 88 to 108 MHz, 108 to 136 MHz is reserved for aircraft communications and navigation.  136 to 174 is called the High VHF band (the common "Scanner" band), the old analog TV channel 7 was 174 to 180 MHz.

1st Generation

It appears that the first generation sonobuoys only had 16 channels spaced 0.75 kHz apart between 162.25 and 173.50.  This was probably done using a single crystal in tube type electronics circuit.
Note:  The eBay listing for a sonobuoy receiver "R-156/ARR-16B Sonobuoy Receiver 62-72 MCs." is in error by leaving off the "1" in front of the frequency.

2nd Generation

At some point (When?)  the channel spacing was cut in half.  At that time to maintain channel number comparability with the old system, the new channels were added in between the old channels as shown in the table. (chan 1) 162.25 to 173.50 with spacing of 0.375 MHz.
The R-1170 ARR-52A sonobuoy receiver has 31 crystal controlled channels.

3rd Generation

At some point (When?) the total number of channels was increased to 100 (or 99?) by adding channels starting at 136.000 MHz (chan 32) and going to 161.125 (chan 99) with the same 0.375 MHz channel spacing.  Is there a channel 00?
So the band plan in frequency order is,  the new lower frequency channels from 136.000 to 161.125, skipping 161.500 and 161.875 (Why?), then the 2nd generation channels from 162.250 to 173.500 MHz.

USQ-46 (USQ, below)

The USQ-46 receiver has 3000 channels with a 6.25 kHz channel spacing.   
If the received frequency is below 162.000 MHz then the Freq_MHz = 145.525 + <chan#> * 0.00625,
if the frequency is equal or greater than 162.000 then Freq_MHz = 162.000 + <chan#> * 0.00625.
So there's a strong sonobuoy flavor to how the USQ-46 does channel assignment.
If you know about this, tell me.

Black Box

This is a beacon transmitter that just transmits a narrow pulse in the sonobuoy frequency range.  But, the signal requires a receiver with about a 150 kHz channel bandwidth.
Since the only information it sends is it's center frequency, probably one of a small list of possible frequencies and one of two possible duty cycles the process gain is extremely high. 

During the Vietnam era there were airplanes circling over areas where ground based sensors were placed to relay the VHF sensor signals to a ground station (Wiki).  This page was made because of the similarity of ground based intrusion sensors and sonobuoys.  They both work the same way and both have the same reception requirements.

My guess is that today there is a satellite system doing the same thing.  This system would receive in the 136 to 173 MHz range and use digital IF processing, similar to what's done in the HP 4395A combined spectrum network and impedance analyzer.  If that was the case then it would be straight forward to have the ability for this receiver to receive not only sonobuoy signals but also the waveform used by the Black Box.

This makes sense in that the system would have world wide coverage without the need to have planes circling 24/7 like in Igloo White.

The WiNRADiO MS-8118/WSB Sonobuoy Telemetry Multichannel Receiving System (WiNRADiO) covers 136.000-173.500 MHz (custom frequency ranges available) with an IF bandwidth of 30 kHz @ -6 dB.
They also have a WiNRADiO AX-61S Sonobuoy Telemetry Antenna that covers 135 to 175 MHz.
The G315i receiver can be ordered with an optional hardware wide band demodulator that's the same as in the sonobuoy receiver: WR-G315i Receiver Options or for the WR-G315e Receiver Options .
Note the black box beacon transmitter may be associated with the SEAL Delivery Vehicle (Wiki: SDV).
That would be perfect for receiving the Black Box signal (thanks to Chip Veres) for letting me know about the MS-8118.  But this raises a new question, what else generates such a wideband signal?

The transmission frequencies of some black box units are: 164.5375 & 164.5875 MHz.  Note neither of these is on channel 4 (164.50 MHz) and they differ by 50 kHz, not likely an accident.

Distributed Sensor Networks, Second Edition: Image and Sensor Signal Processing (Chapman & Hall/CRC Computer and Information Science Series)

Iyengar, S. Sitharama- book on order 14 Nov 2015 has info on Igloo White and may have some insights into the satellite system?

Chan	Freq	Chan	Freq	Chan	Freq
1	162.25	6	166.00	11	169.75
17	162.625	22	166.375	27	170.125
2	163.00	7	166.75	12	170.50
18	163.375	23	167.125	28	170.875
3	163.75	8	167.50	13	171.25
19	164.125	24	167.875	29	171.625
4	164.50	9	168.25	14	172.00
20	164.875	25	168.625	30	172.375
5	165.25	10	169.0	15	172.75
21	165.625	26	169.375	31	173.125
				16	173.50

Channel 15 (172.75 MHz)  is used as an emergency search and rescue frequency.

Command Function Select (CFS)

The aircraft can transmit to the sonobuoy to change the commands while it's floating in the water which is much better than the old way of making the command decisions prior to launch.
The UHF frequencies used for this are: 282.900, 291.300, 291.400, 291.500 MHz

Directional Frequency Analysis & Recording type acoustic sensor (DIFAR)

These buoys use directional hydrophones (Wiki) covering 5 or 10 Hz to 2400 Hz combined with a magnetic bearing sensor and transmit this information.
They can be used to passively listen, to listen for reflected pings or the shock wave from a small explosion.
Whale researchers use them (Tools > DIFAR Sonobuoys).

Because the lower frequency limit is below Hi-Fi audio, consumer grade tape recorders could not be used so instrumentation type recorders were used.

With the advent of Digital Audio Tape (DAT) recorders the DIFAR signal could be recorded on a DAT tape.
The following is a frequency spectrum of the DIFAR signal with a voice channel added for use with a DAT tape recorder.

Analog circuitry, like using the LM1496 Balanced Modulator-Demodulator can be used to manipulate these signals.

Note seismic sensors (geophones) respond to frequencies below 10 Hz so there's an overlap with DIFAR and other hydrophone frequencies.

DIFAR Patents

3116471 Radio sonobuoy system, Jesse J Coop, Dec 31, 1963, 367/3, 367/5, 367/113, 367/101, 367/126, 367/115, 318/638 -  In the present invention a multi-beam directional hydrophone is utilized in a radio sonobuoy system whereby an immediate quadrant location and an accurate distance measurement of a reflecting object from the multi-beam directional sonobuoy can be obtained from a single pressure pulse generated in the water area of interest.  - DIFAR

3987404 Underwater Direction Finding System is the patent that defines how a directional (the DI in DIFAR) sonobuoy can be made.

3987404 Underwater Direction Finding System, Sanders, (filed: Nov 3 1967) Issued: Oct 19, 1976, 367/3; 367/125; 367/126 - "An underwater direction finding system includes a pair of directional hydrophones and a compass in a novel arrangement which associates the signals from all three elements with a single subcarrier.  Subsequent demodulation of the subcarrier signals in an airplane or ship then provides directional information directly referrenced to the earth's magnetic coordinates." Calls: US2754493 Indicator for Sound Direction Finder Feb 4, 1955 1956 LIPPEL US2837730 Deflection Method for CRT Aug 4, 1952 Jun 3, 1958 IAUAEM US2867788 Object Locating Systems (sub hunting) Feb 27, 1943 Jan 6, 1959 HARRY US3022462 Frequency Modulation Detector System (see below) Jan 19, 1953 Feb 20, 1962 FREQUENCY MODULATION DETECTOR SYSTEM US3148351 Directional Hydrophone System (see below) Jun 12, 1961 Sep 8, 1964 FILTER US3160850 Underwater Locating Apparatus (Glomar Explorer?) Dec 27, 1960 Dec 8, 1964 DUDLEY US3176262 Directional Sonar Systems (dipping SONAR) Apr 6, 1960 Mar 30, 1965 EHRLICH ETAL, DIRECTIONAL SONAR SYSTEMS Referenced by: US4872146 May 23, 1988 Oct 3, 1989 Canadian Patents & Development Limited Method and apparatus for simulating phase coherent signal reflections in media containing randomly distributed targets US4879694 Mar 4, 1988 Nov 7, 1989 Rockwell International Corporation Difar demultiplexer circuit US5253223 Apr 27, 1992 Oct 12, 1993 Den Norske Stats Oljeselskap A.S. Seismic device US5265066 Apr 27, 1992 Nov 23, 1993 Den norske stats oljeselskap a.s Seismic cable US5442590 Apr 27, 1992 Aug 15, 1995 Den norske stats oljeselskap a.s Seismic cable device US6108270 Jul 6, 1999 Aug 22, 2000 Torpedo seeker head having directional detection independent of frequency US6622647 Jun 26, 2001 Sep 23, 2003 Active noise cancellation for a torpedo seeker head US8059485 Jun 4, 2008 Nov 15, 2011 NEC Corporation Communication system, information collecting method and base station apparatus

3461421 Advanced Direction Finding Sonobuoy System, (Collins Radio), Aug 12, 1969, 367/124; 367/3; 367/6; 367/125; 367/126; 367/128

Calls:
2898589 Hemispherical Acoustic Phase Compensator, F.R. Abbott, Aug 4, 1959,
3022462 Frequency Modulation Detector System, Philco, Feb 20, 1962, - sonobuoy to aircraft

sonobuoy includes mag bearing and hydrophone.
Calls:
2476301
2631270

3148351 Directional Hydrophone System, Bartlett Labs, Sep 8, 1964, 367/125; 367/3; 367/124

Calls:
2903673
2946980
2977570
3000078
3027627
3030606

3239799 Sonar Directional Beam Focusing System, GE, Mar 8, 1966,

Referenced by:

			ignee	Title
US4078222	Nov 20, 1969	Mar 7, 1978	The United States of America as represented by the Secretary of the Navy	Direction determining apparatus
US4371957	Dec 12, 1969	Feb 1, 1983	Her Majesty the Queen in right of Canada, as represented by the Minister of National Defence	Antisubmarine warfare system
US4604733	Jan 3, 1984	Aug 5, 1986	Westinghouse Electric Corp.	Apparatus for determining range and bearing
US4653033	Oct 4, 1984	Mar 24, 1987	Thomson-CSF	Goniotelemetry system
US4691305	Sep 5, 1985	Sep 1, 1987	The United States of America as represented by the Secretary of the Air force	Automatic attenuator for sonobuoys
US4872146	May 23, 1988	Oct 3, 1989	Canadian Patents & Development Limited	Method and apparatus for simulating phase coherent signal reflections in media containing randomly distributed targets
US4914734	Jul 21, 1989	Apr 3, 1990	The United States of America as represented by the Secretary of the Air Force	Intensity area correlation addition to terrain radiometric area correlation
US5859915	Apr 30, 1997	Jan 12, 1999	American Technology Corporation	Lighted enhanced bullhorn
US5885129	Mar 25, 1997	Mar 23, 1999	American Technology Corporation	Directable sound and light toy
US7088830	Mar 18, 2002	Aug 8, 2006	American Technology Corporation	Parametric ring emitter
US7109789	Jan 21, 2003	Sep 19, 2006	American Technology Corporation	Modulator—amplifier
US7224219	Sep 18, 2006	May 29, 2007	American Technology Corporation	Modulator-amplifier
US7564981	Oct 21, 2004	Jul 21, 2009	American Technology Corporation	Method of adjusting linear parameters of a parametric ultrasonic signal to reduce non-linearities in decoupled audio output waves and system including same

4114137 Directional sonobuoy, Russell I. Mason, John R. Dale, Secretary Of The Navy, FIled: Dec 19, 1974, Pub: Sep 12, 1978, 367/171, 441/1, 441/28 - 

Earth's Field Magnetic Detectors

Also see my Flux Gate patents web page.

2252059 Method and a device for determining the magnitudes of magnetic fields, Gustav Barth, Priority Dec 24, 1936, Pub Aug 12, 1941 - rod fluxgate
2560132 Unbalanced magnetometer, Schmitt Otto H, Jul 10, 1951, 324/255, 340/870.33 - second harmonic
2488341 Detection system, Thaddeus Slonczewski, Bell Telephone Labor Inc, Nov 15, 1949, 324/246, 340/870.33, 324/254, 324/253 - moving parts

Calls:
2485931 Magnetic field strength indicator - no moving parts
2468968 Magnetic field strength indicator
2027393 Cathode ray device
2047609 Magnetic field direction and intensity finder
2053154 Direct-current indicator
2438964 Magnetic field detector - second harmonic magnetometer

Magnetic buoy

2397137 Magnetic controlling device, Glennon James B, Maltby Wilson R, Sellman Albert H, filed Jun 25, 1941, pub Mar 26, 1946, 340/850, 324/259, 340/551, 102/417

2644243 Control compass, George E Breeze, Russell I Mason, Us Navy, Filed: Nov 20, 1944, Pub: Jul 7, 1953, 361/280, 33/363.00Q -  for use in sonobuoy, eliminates vertical component of Earth's mag field for more accurate mag bearing (for: DIFAR)    

3526002 Magnebuoy, Ramond C Waddel, Filing date Mar 31, 1960, Publication dateAug 25, 1970 (maybe withheld secret), 340/852

Bathythermograph Patents

The early Spilhaus Bathythermographs were based on a stylus marking a microscope slide blackened soot.  This basic design went through many improvements.  It was deployed on a line and recovered to get the glass slide.  Note while each of these has a serial number and a custom made calibration chart for that serial number in order to convert the data on the glass slide to  depth and temperature.  That data was used to determine the Assured Range (AR) of a sonar system.  Note the sound is bent downward when the water gets colder with depth and when a submarine on the surface is beyond the AR distance it is invisible to the sonar.

The Submarine Bathythermograph (SBT) is built into the sub and records depth and temperature on paper cards.  The sound man will know from charts that contain BT data, as well as other data related to sonar, what to expect in the current operational area.  But to get a more accurate picture a deep dive with a fresh BT card in the machine or dropping a BT sonobuoy (SSQ-36 , ST-1from the surface will give an accurate picture of the current conditions.  A lot more info on BT in An Ocean in Common (Ref 4).

2297725 Bathythermograph, Spilhaus Athelstan F, Submarine Signal Co, Filed: Aug 10, 1938, Pub: Oct 6, 1942, 374/136, 374/E01.3, 73/729.1 - marks smoked glass slide with pressure & Temp

2515034 Bathythermograph, William M Ewing, Allyn C Vine, Us Navy, Filed: May 27, 1944, Pub: Jul 11, 1950, 374/136, 73/300 - rapid response to temp & pressure (recording inside unit)

2629083 Expendable radiosonic buoy, Barkson Joseph A, Mason Russell I, Mcnary James C, Filed: Sep 21, 1944, Pub: Feb 17, 1953, 367/3, 343/709, 455/99, 441/33, 441/23, 343/705, 343/901 -
2703009 Bathythermograph, Ewing William M, Vine Allyn C, Filed: Nov 28, 1945, Pub: Mar 1, 1955, 73/178.00R, 346/120, 73/712, 73/742, 374/E01.3, 73/299 - for use on subs

2683987 Method of ascertaining unknown data, Earl W Springer, Filed: Jan 2, 1946, Pub: Jul 20, 1954, 374/100, 356/393, 73/584, 367/99 -  the importance of depth v. Temp data for sonar. - uses optical comparison of a BT glass slide plot with a catalog of plots to get a rapid interpretation of the meaning in terms of SONAR.  

3098993 Sonobuoy-bathythermograph system, Coop Jesse J, Jul 23, 1963, 367/134, 374/E01.3, 340/870.17, 340/870.6, 367/185, 367/3, 374/E01.4, 73/170.34 - sound output that can be heard by sonobuoy.
3119090 Sea depth determination air survey means
3135943 Underwater thermometric apparatus, Welex Electronics, - sets off a small explosion at a specified amount of change in temperature.
3273393 Bathythermograph, Spark Wallace R, Douglas Aircraft Co Inc, Sep 20, 1966, 374/136, 340/852, 73/170.34, 374/E01.3, 73/292, 367/134, 374/142 -


2402143 Parachute pack, Arenstein Gilbert H, Sec of War, Filed: Jun 7, 1944, Pub: Jun 18, 1946, 244/138.00R, 455/99, 343/709, 244/151.00B, 343/889, 441/11, 367/4, 116/26, 455/96 - for sonobuoys with antenna through center of parachute.

3441901 System for measuring sound velocity in water as a function of depth, Cawley John H, Schiff Daniel, Us Navy, Apr 29, 1969, 367/131, 367/134, 73/597, 367/89 -  a sound projector, triggered by a surface ship sends a ping to the ships sonar which measures the time delay.  Knowing the depth and horizontal distance to the probe allows a direct readout of the sound velocity. 
Note in 1969 the ability to measure short time intervals was much poorer than today, so the length of the base line can be shortened from maybe 100 feet to something more reasonable like a yard so that the device could be permanently mounted on a ship or sub.

4215571 Expendable bathythermograph for use under ice, Ralph P. Crist, Secretary Of The Navy, Aug 5, 1980, 73/170.29, 374/E01.018, 374/E01.004, 73/300, 73/170.34, 374/136 - a housing for the (SSQ-36?) that floats up and when it hits the surface or the bottom of the ice releases the (SSQ-36?).

Reserve Batteries

Reserve batteries have the electrolyte and anode separated.  This allows them to be stored for more than a decade and still retain their full capacity when activated.  Example applications are hearing
aid batteries, artillery shells and sonobuoys, weather balloons, torpedoes.

Salt water activated magnesium

Because of the green particles that can be seen on the black plastic I suspect the chemistry is one of the following in the SSQ-53B:

• Magnesium/Cuprous Chloride
• Magnesium/Cuprous Iodide-Sulfer
• Magnesium/CuprousThiocyanate-Sulfer

Reserve Battery Patents

A reserve battery is one where the electrolyte is stored seperated from the electrodes.  They can sit for decades and when activated (heat, water, gas, mechanical force) are then a battery.
Wiki: Water-activated battery

2474716 Salt-water battery, John T Beechlyn, Submarine Signal Co, Filed: Sep 18, 1944 (5 year delay), Pub: Jun 28, 1949, 429/82, 429/94, 429/119 - light buoy.  Iron and Magnesium
2590584 Sea Water Battery, Bel Tel Labs, Mar 25 1952, 429/119; 429/152; 429/231.6 - silver chloride on silver & magnesium electrodes in salt water.
2669596 Reserve Battery Enclosure, Navy, Feb 16 1954, 429/8; 116/1; 429/119 -
2699461 Defered Action Battery, Burgess, Jan 11 1955, 429/119; 429/152; 429/162 -
2715652 Electric Battery for Airborne Equipment, Eagle-Picher Co, Aub 16 1955, 429/118; 429/152; 429/162 : -40 to 160 def F operation
3178316 Reserve Battery, Servel Inc, Apr 13, 1965, 429/119; 429/130; 429/210 -
3767933 Power Supply having a Plurality of Power Sources that are Sequentially Placed on the Load One at a Time, Oct 23 1973 307/48; 307/66 -
3966497 Seawater Battery, ESB Inc, Jun 29 1976, 429/119 -
4601961 Bilaminar Seawater Battery, Navy, Jul 22, 1986, 429/119; 429/127 -

Calls:
5395707 Environmentally safe water-activated battery, ACR Elec, Mar 7 1995, 429/119; 429/128; 429/130 -

Salt water activated silver chloride

2564495 Deferred action primary battery, John B Mullen, Burgess Battery Co, Filed: Feb 27, 1947, Pub: Aug 14, 1951, 429/119, 429/152 - plain water activation, for radio B+  
2637756 Deferred action battery, Joseph J Coleman, Milton E Wilke, Burgess Battery Co, May 5, 1953, 429/119 -    
2655551 Magnesium-cuprous chloride reserve battery, Sec of Army, Filed: Jul 31, 1950, Pub: Oct 13, 1953, 429/119, 429/152 -
2699461 Deferred action battery, Milton E Wilke, Burgess Battery Co, Jan 11, 1955, 429/119, 429/152, 429/162 - water activated 

The following water activated batteries are probably all for uses relating to weather balloons or Radiosonde use.
BA-259 Water Activated Battery, NSN: 6135-00-635-6370, Eagle-Picher Ind. Colorado Springs: A: 1.5 & 6  Volts, B: 115 Volts
BA-292.AM Water Activated Battery, NSN: 6223-00-032-2387, Wisco Div, ESB Inc, Raleigh NC - for flashlight bulb on balloon
BA-380/AMQ-9, NSN: 6135-753-2276, Ray-O-Vac division, Mfg Co. Wonewoc, Wisconsin - for AMQ-9

Light, Emergency Sea Rescue Marker

A water activated battery powers a GE 131 flashlight lamp (1.3 Volts, 1.3 Watts, i.e. draws 1 Amp)

Box Stk. No. 6230-299-5653 Type J-2, with Water Activated Battery. Spec. MIL-L-7396A(ASG) Application: Life Rafts One Each    Item No. 4 Contract No. AF 30(635)-23525 Fulton Mfg. Corp. Mfg/Contr., Wauseon, Ohio A-1 A8-  8/61 Reinspection Date.......... 8/64

Plastic Housing Light Sea Rescue Marker Type J-2   MIL-L-7368A(ASC) Specification Part No. N-45A Fulton Mfg. Corp. U.S. ---------------------------------------------- Caution: Do Not Remove Plug for Inspection.

Photos

Fig 1  Box

Fig 2 The Aluminum tube is to protect the plastic light housing from being broken and is supposed to be in place when deployed.

Fig 3 There are loose crystals in the left end. There is a small opening that shows up as a light circle about where the rubber plug is located.

Related Marker Lights:

SDU-30
SDU-5/E

Table of Sonobuoys

Naval Consolidated Sonobuoys @FAS -

	Function	Start	End	Links
AN/CRT-1	5 vacuum tubes single channel FM transmitter between 67 & 72 Mhz. See Roswell Connection below where this was used with "disk microphones" on Project Mogul CANADIAN LANCASTER - AN/CRT-1 SONOBUOY SYSTEM - drawing of aircraft equipment & buoy Chapter 16 - SOFAR, HARBOR DEFENSE, AND OTHER SONAR SYSTEMS Naval History - RADAR - MAD and CRT-1 CRT-1A: 67.7 to 71.7 MHz CRT-1B: 62.9 to 66.9 MHz	Jun 1942
AN/CRT-4	RDRH Mechanical rotation of hydrophone (Ref 6)	Feb 1943
AN/CRT-1A	6 channels	1944
AN/CRT-1B	separate web page (Differences to -1 and -1A? Let me know)
AN/SSQ-1	upgraded CRT-4	not UK SSQ-20
SSQ-2			15 Feb 1955	jproc SS-383
1950 start of: Sound Surveillance System (SOSUS)
SSQ-20		1951
SSQ-2B	Julie explosive	1956
AN/SSQ-15	Julie RO B-size
SSQ-23	Julie	1956	19 Nov 1964
SSQ-28	Jezebel-LOFAR	1960	19 Nov 1964
SSQ-36	BT The BT sonobuoy is an expendable thermal gradient measurement sonobuoy that operates on one of three or one of 99 Radio Frequency (RF) channels. It consists of a thermistor (Wiki) temperature probe that descends through the bottom of the sonobuoy canister producing a continuous reading of temperature versus depth. The thermistor temperature probe will descend to 1000, 2000, or 2625 feet, depending upon the sonobuoy selected. Fig 36-01 Tubes Ship: 7" x 45" Launch: 5-3/8" x 39-1/4" Housing: 4-3/4" x 35-7/8" Fig 36-02 Launch Tube Cap - twist and lift. Fig 36-03 Housing (what drops through air and lands in ocean
SSQ-38	30day omni-directional LOFAR (replaced SSQ-28) 10 to 6,000 Hz 31 chan	1964	1 June 1961
SSQ-41	single hydrophone	1964
SSQ-47	(replaced Julie explosive system) active ping omni directional range only replaced by SSQ-50	1968
SSQ-48	replacedd by SSQ-41B		26 Feb 1981
SSQ-50	CASS
SSQ-53	31 RF Channels 10 Hz - 2.4 kHz 90 feet fixed depth		Sep 1967
SSQ-53A	90 or 1000' depth 1 or 8 hours
SSQ-53B	DIFAR fitted with microprocessor controlled EFS capabilities, with three depth selections [100, 400 or 1000 feet], three operating time selections of 1, 3 or 8 hours, 99 vhf channels. Operation Before inserting the launch tube into the aircraft chute the sonobuoy is programmed for operational life, channel number and depth by using the SET button.  If done incorrectly pulling the TEST plug for a few seconds will allow reprogramming.  Power for this comes from a couple of coin cell batteries.  The correct programming can be confirmed by pressing and holding the VERIFY button for a couple of seconds. When forced from the aircraft chute by means of compressed air the lid is blown off the launch tube deploying the parachute on the metal sonobuoy housing.  The plastic launch tube stays in the chute. When the metal sonobuoy (Fig 53-8)  impacts the water is starts to sink and water activates the reserve battery.  As soon as the battery has power (probably within a few seconds) the squib retaining the large spring allows an arm to puncture a compressed gas bottle inflating the buoy/antenna (Fig 53-17).  At the same time, depending on the programmed depth one or both rods (Fig 53-21) are driven down to set the amount of cable that will unspool controlling depth of the sensor.  A very short time later the three main components of the sonobuoy are separated as the metal outer housing is blown clear and sinks. With power the radio transmitter begins to send it's signal. The duration may be determined by a simple electric timer that shuts off the transmitter after the programmed time, or . . .  there may be some provision to do more? Although very old I believe this unit would still work. Fig 53-1 Launch Tube 5-3/8" diz x 39-5/8" long dated 5/87 - it's 12/11 now so this is just under 25 years old. The shipping container probably was left on the ground. If you know the deployment sequence let me know what it is. Fig 53-2 Top: Channel (01 to 99), Duration (1, 3 or 8 hrs), Depth (90, 400 or 1000) Ft., Verify What was a transparent membrane has aged and is falling apart.  When intact would provide a moisture barrier so the decissant  could keep the inside dry. Fig 53-3 Sonobuoy Launch Container LAU/126A NOO 83-86-C-0007 .OT 036 Fig 53-4 LAU/126A Launch Container Cap Fig 53-5 Cap Off by removing 4 black plastic clips It's not clear how the sonobuoy was programmed and in what order loaded into the aircraft launch chute. Fig 53-6 Inside the Launch Tube, marked: Caution: - Disengage before launch Caution: Spring Loaded Fig 53-7 SSQ-53B Ready to launch (string holding spring snare) The metal SSQ-53B housing is 4-3/4" O.D. The label just to the right of the depth scale says: WARNING Remove Plug Prior to Test EFS Battery may be damaged if pins 1 and 2  are shorted or voltage is applied across pins 1 and 2. Voltage applied to pin 3 may cause high velocity ejection of top plate. Reinstall plug before use. Fig 53-8 With parachute deployed The gray plastic cap was preyed off instead of submerging in water and dissolving the two metal links? Fig 53-9 There are three functional parts.  The right is the antenna-buoy cover and receiver/transmitter, the center is cable spools and the bottom (left) is the sensor. Fig 53-10 Three Major Components: Left: Radio, Antenna, Battery Center: cable Right: Sensor Fig 53-11 Sensor, marked: Sparton Corporation 120-0127-002 Clock Number: 0358     Date 06/03/87 {bar code] SIN: -67.1 db    COS: -68.4 db      OMNI: -72.1 db the latter three parameters are related to the DIFAR aspect of the sensor. The black cylinder hanging out the bottom is probably the omni hydrophone. Note:  There's a single green/white wire (cable) going to/coming from the sensor. I expect it's a small coax cable, but it remains to be seen. Fig 53-12  Radio Buoy Fig 53-13 With cap pulled off and buoy opened, but not inflated. There appears to be small wire antenna with a resistor at the top. Fig 53-14  Test Socket & Memory Battery Test Socket cap held by O-Ring, need big pliers to pull/twist it out. There was a jumper plug  in the socket, more later. Memory Battery and PCBs There's a big spring that can puncture what's probably a good size CO2 cylinder in order to inflate the buoy/antenna.  There's what looks like a fusible link holding the spring in tension that could trigger the gas. Also at the bottom of the PCB chamber there are a couple of lever arms that have a resistor wrapped around their ends.  If the resistor was exploded (over powered) then it would release these arms to do something (maybe control the depth through the cable spools? The two coin cells are in the white plastic holder.  They provide about 6 Volts and are still good. On the left board there are three red wires (Battery +), a bare stub where I wiggled off the battery + wire, and a yellow wire (to socket pin 3).  The bare wire at the top (just under the coin cells) that's soldered to a lug on the central metal plate is ground (same as the cast metal frame where the battery- wire connects.). Fig 53-16 Battery Fig 53-17 Main Battery held to cylinder with double sided foam tape. 1 lb 11 oz. 4-1/4" hi x 3-1/8" w x 2-9/16" d (11 x 8 x 6 cm) There is a hole on two sides just under the top cover to allow water to enter. This is a water activated reserve battery. 1986 Mfg date. Fig 53-18 In the other photos you can see green deposits on the inside of the radio/buoy black plastic.  I think that's because this reserve battery contains Copper in a form that allows it to escape.  This may be a limiting factor for the shelf life.  The Copper deposits are probably the result of the failure of the moisture proof membrane that covers the programming push button switches.   Once the moisture in the air gets to the reserve battery it's going to become a carrier for the copper and also will lower the battery capacity. Idea:  Rather than depend on the moisture proof membrane (and Desiccant (Wiki)) to keep the reserve battery fresh, it should be in a compartment that's sealed until the metal housing is separated from the launch tube.. The two coin cells are still good condition after almost 25 years since this was manufactured.   4262069 Lead chloride battery plate, John L. Devitt, Douglas E. Johnson, Robert S. Willard, Sparton Corporation, Apr 14, 1981 - Cites: 3468710 Sea water battery, Jerome Goodman, Philip I Krasnow, Nuclear Research Associates, Sep 23, 1969 - Cites: 2692215 Alkaline dry cell, Ruben Samuel, Oct 19, 1954 - 3005864 Sea water battery, Duncan T Sharpe, Bell Telephone Lab, Filed: Mar 29 (16 year delay), 1945, Pub: Oct 24, 1961 - maybe the Mk 18 torpedo (Wiki) Fig 53-19  High Pressure Gas bottle to inflate buoy/antenna There are three PCBs: Blue: modulator & RF exciter Green:  I/O panel Tan: RF Power Amp Fig 53-20 Test Socket Message Socket Pin Ohms to Gnd Ohms to Bat+ Plug 1 1M8 1M8 1-7 2 876k 1M4 3Note1 >1M 0.2 3-4 4 0.2 405k 3-4 5 1M 1M 6 1M 1M 7 0.1 405k 1-7 Note 1: pin 3 is connected to one side of the squib that can cut the lanyard holding the arm that will puncture the high pressure gas for deploying the buoy/antenna. Pins 7 & 4 are connected to the ground bulckhead (0.0 Ohms). Pin 3 is connected to the red battery wire (0.0 Ohms) The jumper plug connects: 1 to 7 3 to 4 With the jumper plutg removed: Red test lead to red battery wire (black lead to ground) = 1M00 Ohms Black tet lead to red battery wire (red lead to ground) = 401k Ohms Pin 1 is connected to the negative (black wire) leading from the two stacked coin cells). The jumper plug connects pin 1 to pin 7.  Pin 7 is connected to the micro controller.  So these two pins relate to zeroing the programming. If you have information on how the test socket is used please let me know. Fig 53-32 Test Socket Schematic See Fig 55-29 & Fig 53-31 for photo of Fuse 1 (LE  1A) A few of possible reasons for placing a fuse directly across the reserve battery.  One or more of them might be the reason. For Now I'll just remove the fuse. 1) Shorting the main power supply protects the squibs are from being     fired by static or electromagnetic fields (like high power transmitters on board ships). 2) The reserve battery may like activate better when heavily loaded.  Note:  The      BA-4386 Magnesium battery needs to see a heavy load in order to fully activate. 3) When the fuse blows the battery is delivering at least 1 amp and that surge current      would next go to blowing the squibs.  This might be more reliable than ramping up      the squib voltage. Pins 5 & 6 each connect to one of the pins on the micro controller.  The Test plug (cable) probably has a jumper between pins 1 & 7 to connect the EFS (coin cell) battery thus powering the micro controller, and when it's powered up the test socket pins 5 & 6 can be used.  But for what?  Data In/Out, firmware programming, verification check sum, something to do with the hard wired option jumper to the upper right of the LCD housing? let me know.  Fig 53-21 Buttons (now working) maybe because of cyclying the plug. Pressing and holding Verify for a couple of seconds will show the function settings. To change the settings the plug must be removed for a few seconds. Pressing SET starts the channel number counting 0 to 9 to 0. Pressing SET fixes the tens digit and the units start counting pressing set fixes the channel number and the life bars start cycling.  Pressing SET sets the life and then the depth bars start cycling, pressing SET fixes the depth.  Now pressing Verify for a few seconds will display the function settings. They were set for: 1 hr, chan 63 & 1000' Now set for 3 hrs, chan 54 and 400'. Fig 53-22 EFS LCD (plug shown installed) Fig 53-23 Depth Selection The two levers are either in the position shown or they are pushed toward the center to select how much cable is deployed.  The selection is made by the two blue plastic actuators using a push (or pull) of the rod with the spring.  Note this rod is smooth and would not support a rotary motion.  Also the two levers in the bottom of the radio compartment work in an up or down fashion, not in a rotary fashion.  See Fig 53-9 and a close up from it Fig 53-22 below.. Fig 53-24 Close up photo of depth selection blue plastic parts. Fig 53-25 Cutting Squib Wires Three red wires have been cut deactivating the three squibs so DC power can be applied. Test Socket Resistance readings after cutting the wires: Pin Ohm to Gnd Ohms to Bat + Plug 1 1M9 OL 1-7 2 860K OL 3 >1M 1.9 3-4 4 0.6 >1M 3-4 5 1M0 1M3 6 1M0 1M6 7 0.5 1.9 1-7 Gnd to Batt+ (w/0 Plug) = 1M0 Gnd to Batt+ (w Plug) =  0.7 There is still a dead short across the battery terminals! pin3 is yellow wire to Battery + terminal (and red wires) pin 4 is the metal frame (battery -) the black battery wire with the internal tooth lug. This is confusing. The hi pres gas squib is 36.2 Ohms. One of the depth squibs is 18.5 Ohms (red to violet) not to ground. The other depth squib is 18.3 Ohms (red to blue( not to ground. These may be 1/8 Watt 18 Ohm resistors. Rated power would be at 1.5 Volts, 10X power at 4.7V, 100X power at 15 Volts, so if the battery is about 15 volts the resistors would fail mechanically. Note the plug must be installed for the progrmming to work, so operation without the plug is not an option.   The plug has a jumper between pins 3 and 4 that is part of the path shorting the battery + and - terminals. The coax feeding the antenna reads 42.7 Ohms.(resistor is Yel-Org-Blk-Red Fig 53-26 Green Cable 10K0 Ohms either polarity. This joint is located on the black plastic bottom plate of the Transmitter section. White to White, Green to Green. See: Fig 53-10 and Fig 53-12. How to take apart the transmitter?  It may be possible to push everything out the bottom, but that would break the two push button switches.  Probably the best way is to saw from top to bottom at two places 180 degrees apart. Fig 53-27 The switch buttons are mechanical working through a rubber boot and can be pulled out of the plastic housing. After letting the top sit overnight after applying some Kroil to the joint between the plastic housing and the metal plate with 0_ring seal the assembly pressed out the bottom easily.  It was necessary to unsolder the antenna cable and the green wire to isolate the top section. Fig 53-28 RF Amplifier Tan PCB from top section The antenna was connected at the top of this board where the notch is. Gnd to the left and center to the right of the notch. This is probably the Tx power amplifier and antenna matching/filtering board. Fig 53-29  Command and Control Board Green PCB from top section. This is the digital board. I doubt the micro controller is doing anything with the sensor data, so it's probably running at a very slow clock frequency to conserve power. So there's no need for a crystal for it. There are three 2N6724 2 Watt NPN Darlington transistors just to the left of the push buttons used for firing the three squibs.  The collectors go to the squibs and all three emitters are connected to the bulkhead ground plate. Top: RF Amp board depth squib Center: Synth board depth squib Bottom: CO2 Maybe the transistor that blows the antenna squib is on the RF amp board? Above the upper right corner of the black plastic LCD housing thre is a row of 6 holes and a jumper is installed in the right most of these.   What option is this selecting?  Let me know. Fig 53-30  Synthesizer and Modulator Board Blue PCB from top section. This board interfaces with the sensor package. The crystal at the lower left is marked: 10.2985 MHz.  This is a non standard value, see my Crystals web page. Maybe related to the DIFAR spectrum. This board seems to be mostly analog in nature. On the bulkhead plate at the bottom there are the two depth programming levers. As shown the squibs (resistors) are intact and the lever is held in the down position. The two rods are spring loaded and trying to lift up.  When the squibs are broken the depth programming rods are forced up by their spring. At the bottom right the green/white sensor cable can bee seen coming through a hole and connectionto two pads. All three squibs measure 500K Ohms to Bat+ and open to Ground.  So they are not causing the dead battery short. The data codes on the ICs are 1984, 1985 & 1987. 6 Jan 2012 - New Idea about the direct battery short. The short may be part of a Safe And Arm system that would prevent the buoy from becoming active prior to an actual launch.  This may be a common system used not only on sonobuoys but also things like countermeasures equipment like flares and chaff dispensers. If that's the case then something about the pneumatic launch would disable the short. Fig 53-31  Fuse on digital PCB This appears to be the cause of the dead short across the reserve battery terminals. Power Up (with sensor disconnected, antenna attached) For about 15 seconds the current is in the 30 ma range then jumps up to150 to 200 ma when the transmitter turns on. After battery power the Verify button does not work. The battery voltage appears on the green/white cable. On reconnecting the green cable between the floating buoy and the sensor. Buoy The resistance between the two wires and ground is: left: 1M and right 10k. The resistance between the two wires and Batt+  is: left: 0.2  and right  1M Sensor The resistnace between either wire and the sensor metal is an open circuit. So as of 12 Jan 2012 it's still not clear how to be sure the polarity is correct to reconnect the sensor. Thanks to Ugo in Italy there are two conductors in the cable, one supplies power to the sensor package (which has input filter caps) and the other is the audio signal to be modulated onto the transmitter.  Seawater forms a ground return between the floating transmitter and the sensor.  This is confirmed by the book The Ears of Air ASW. pg 241.		1984
SSQ-53D	Dwarf "G" size version of the B	1991
SSQ-53D	DIFAR only sensor, 90, 400 or 1000 feet, no CFS -53D(2) 5 Hz - 2.4 kHz 1/2, 1, 2, 4 or 8 hours -53D(3) sea state 6	2003
SSQ-53E	Digital version Additional hydrophone @ 45' for CSO CFS 100, 200, 400 or 1000 feet AGC 91.44 cm long
SSQ-53F	DIFAR, CSO made by combining the 305 cm long SSQ-53E & SSQ-57 NSN 5845-01-475-9870 adds CO hydrophone with directional units (replaces SSQ-57) CFS Rx - single channel UHF Tx - 96 selectable frequencies (136 - 173.5 MHz), 1W 90, 200, 400, 1000 Ft.	2000
SSQ-57A	Calibrated-LOFAR 10 to 10,000 Hz See separate web page	1972
SSQ-62	DICASS FM sweeps	1976
SSQ-62C	99 channels	1993
SSQ-62E	Command Function Select Electronic Function Select 96 chan 136.000 - 173.500 MHz CW Out: 6.5, 7.5, 8.5 or 9.5 kHz			Sonobuoy Tech Systems
SSQ-77A	VLAD	1981
SSQ-77B	" more hydrophones, 2 depths, 2 beams	1989
SSQ-77C	" adds RF command function selection
SSQ-86	DLC
SSQ-101	ADAR	FY97
SSQ-110	EER		30 July 1997
SSQ-125	advanced EER ADLFP sound source used with: ADAR sonobuoys like SSQ-53F, SSQ-77C and SSQ-101
SSQ-536	BT
SSQ-801	BARRA
SSQ-906	LOFAR Omni
SSQ-926	ALFEA, GPS
SSQ-937	BT
SSQ-954	DIFAR
SSQ-955	HIDAR
SSQ-963D	CAMBS			Janes
SSQ-981	BARRA

Types of Sonobuoys

ADAR: Advanced Deplorable Acoustic Receiver
ADLFP: Advanced  Deplorable Low Frequency Projector
ALFEA: Active Low Frequency Electro-Acoustic
BARRA: means Listening in an indigenous Australian language - The Barra Sonobuoy System, Barra Sonobuoy Design, horizontal array
BT: Bathythermograph
CAMBS: Command Activated Multi-Beam Sonobuoy
CASS: Command Activated Sonobuoy System
CFS: Command Function Select (set function with 2-way radio when buoy is in water)
CO: Calibrated Omni type acoustic sensor (5 - 20 kHz)
CSO: Constant Shallow Omni type acoustic sensor (30 - 5000 Hz)
DICASS Directional Command Activated Sonobuoy System
DIFAR: DIrectional Frequency Analysis & Recording type acoustic sensor (5 - 2400 Hz)
EER: Extended Echo Ranging - uses small explosion as sound source see patent 2402391
EFS: Electronic Function Selector (RF Chan, Life, Depth, Sensor type, AGC)
HIDAR: High Dynamic Range DIFAR
LOFAR: LOw Frequency Analysis & Recording - low cost, the waterfall display good for classifying a contact
RDRH: Rotating Directional Receiving Hydrophone
REFS: optical Remote Electronic Function Select (either while in launch tube (easy) or in water (requires laser))
RO: Range Only

SUS: Signal Underwater Sound

This is typically dropped from a friendly sub hunter aircraft in order to send one of a small number of predetermined messages to a submerged sub.  It uses audio tones around 3 kHz.
Like the CRT-1 Sonobuoy, ST-1 Bathythermograph and the T346/SRT SOS buoy is 3" in diameter so could be used from the Submerged Signal Ejector on a sub.

Description
Mk-84 Mod 0
Got this on eBay with a fake nose cone that's been removed.  It's just the tail shell, but has markings:
DOD Code: SA-06
FSN: 1360-052-1480
Date Pkgd: (blank)
Contr. No.
N00019-67-C-0322
Mfrg. 94117
Ser. No. (blank)
Wt. 6.5 Lbs. Nom.

NONEXPLOSIVE
SUS MK84 MOD 0

There are 4 tapped holes for attaching the transducer/electronics package.  Adjacent to these holes are 4 holes 3/8" dia (total area: 0.44 sq in) that are the inlets for the water activated battery that's inside this tail section.  The center hole at the back is 7/8" ID (total area: 0.61 sq in, i.e. much larger than the inlet hold area. Why?).

Fig 1

Fig 2

Fig 3

(MK-84 MOD 1 SUS uses 3.3 and 3.5 kHz audio to generate 5 codes as messages to a sub.)

          Air to sub communications.

Code	Morse	3.3 kHz	3.5 kHz	Meaning?
1	M	-	-
2	A	.	-
3	I	.	.
4	N	-	.
5		off	cont

If there are standard meanings for these let me know what they are.

VLAD: Vertical Line Array Detector - long range ( 7 km (4+ miles)

Patents

3148618 Underwater signaling apparatus, Joseph D Richard, 1962-03-20 - used to determine optimum depth for SONAR

3724374 Underwater sound source, Navy, 1962-04-27 - used with active sonobuoy, not as signal to friendly sub


Also see the Vaisala  RD93 GPS Dropsonde which is another 3" diameter device launched from the same tube on an aircraft like the P-3.

Sonobuoy Aircraft Systems

	Control Drift - Compute - Reset PDI: BDHI: Marker 1 to 6, GTP: Marker 1 to 6  Insert ASA-20 or AQA-1                                                        ASA-20 or AQA-1                                                   A-B: 1 to 6 Computer Ellipse                    A: Off to 6                   Data Release                B: Off to 6
ASA-31 Julie Control Panel

ASA-20 Sonobuoy Recorder "Jezebel".

The AQA-5 is a 4 channel paper chart recorder.
Youtube video: AN/AQA-5 Acoustic Charts Recorder
P-3 Orion Aircraft - Walk Around -

BDHI: Bearing Distance Heading Indicator
PDI: Pulse Doppler Illuminator
3582871 Ellipictal Computer System, Morris Snyder (Navy), Jun 1, 1971, 367/3; 367/107; 701/300; 708/801 - determines sub position using sonobuoys

AN/ARR-502 Multichannel Sonobuoy Receiver (data sheet, data sheet)

AQA-7(V)1/2 Directional Acoustic-Frequency Analysis and Recording System (DIFAR)

ASQ-114 digital computer has a memory loaded with a large number of sound profiles of submarines and radar- and radio signals for comparing ESM measurements

Forward Looking Infra Red (FLIR) replaced the Low Light Level TeleVision system (LLLTV)

ASR-3 Sonobuoy Reference System (SRS) - used multiple antennas to determine bearing to sonobuoy
Digital magnetic Tape System (DMTS) -

Integrated Acoustic Communication System (IACS) - sub coms

Litton LTN-72 navigation system used with the INS and Doppler navigation systems

ALR-66 (Wiki) ESM systems (Wiki) using the Adaptive Controlled Phased Array System (ACPA)

Deinterleaver Technology for Future ESM systems, Dec 1992 NSWC - each pulse received from a single emitter can be agile in frequency, pulse width, pulse amplitude, pulse repetition interval, but not direction.  So using the Pulse Descriptor Word from the ESM sensor a future deinterleaver can sort out each emitter and differentiate between friendly and hostile emitters.  ESM systems mentioned:
Racal SADIE
IBM Associative Comparator
Anaren ESM Processor
ALQ-32 Inner Processor

Instantaneous Frequency Measurement (IFM) receivers are part of the ESM sensor.  But this type of receiver can have problems with two signals at the same time or with a CW signal anywhere in it's frequency range. The proposed configuration is to use narrow band receivers (many channels) and for each channel two paths, one for angle of arrival and the other for characterization of the received signal.

Sippican Ocean Systems SSXBT Model ST-1

This is one of a number of devices that can be launched from the 3" launcher.

Fig 2 Label

Fig 1 3" dia x 36" long

Some Guidelines for the Submarine-Launched Expendable Bathythermograph (SSXBT) System (DTIC Oct 1981, 50 pages) The AN/BSQ-23 (older) and AN/BQH-7 (newer) have higher incidence of failure than the Bathythermographs used abord surface ships.  This document is to help in recognizing when they have failed.  Typically used to measure ocean temperature v. depth in 100 foot intervals down to 2,500 feet.  This can be used a part of the launch solution for the Mk 48 torpedo.  It seems the sub needs to be at the surface to launch the ST-1.  Because of the hydrodynamics of the ST-1, it's rate of decent is known, it's possible to know the depth by the time since it was on the surface.  It should take 2 minutes 58 seconds to go from the surface to 2,500 feet.  If the sub enters a new ocean front (see map on pdf pg 18) the BQH-1 graph will show a change.  That can be compared to the SSXBT data to confirm correct operation of the SSXBT.  The appendix has 21 example plots each showing a different problem.

The AN/BSQ-23
4518915 Test device for expendable bathythermograph, Philip G. Danforth, Thomas G. Bucko, Kenneth R. Galliher, Joseph T. Lucia, Richard L. Miller, Timothy B. Straw,
Secretary Of The Navy, May 21, 1985, 324/750.01, 324/762.01, 374/E15.001, 374/134 - "...to provide a simulator for testing and calibrating a wide variety of XBT systems used on board surface ships and submarines...."

The BQH-1 Depth-Sound Speed can be used as a check on the SSXBT.  This plots the speed of sound (time delay for a fixed distance) v. depth (water pressure). Either temperature or sound speed units can be used, it's best to use temperature units to allow matching to the SSXBT data.
AD-758 085, Engineering Evaluation of Depth-Sound Speed Measuring Set AN/BQH-1 Manufactured by Dyna-Empire Corp. Garden City, New York.  Contract NOBSR-75772, Navy Underwater Sound Laboratory, New London, Connecticut, 10 March 1961.

Outdoor Intrusion Detectors based on Sonobuoy Technology

Construction

Since the sonobuoy has a cylindrical ( 4-4/7" O.D.) shape it makes sense to have the electronics in the form of cylindrical modules that can be stacked end to end. These modules are about 2-3/4" O.D. and have a circular connector around the outer edge.  For use as an outdoor intrusion detector the hydrophone is replaced with a geophone (Wiki), or other sensor like used to listen for the RF generated from spark ignition engines. 

ARFBUOY Acoubuoy This is an 18 pound steel cylinder 4-3/4"x22". It's designed to be air dropped  with a drag chute and get hung up in the trees.  There is a central tape whip and four ground plane tape whips each 17" long. which is a quarter wave at about 190 MHz.
The central gold colored thing is the microphone.  Note all the holes in the front to let sound it and protrct the microphone from tree limbs.
	Battery This is a battery type I don't recognize.  If you know about it please let me know what it is.	Sound Observer (Locator) Remote Microphone. It's identical to the mike in the acoubuoy. This is the same mike that's in the photo at left with the question mark.  The 5 socket connector is marked: 7004 Deutsh DBA36-10-5SN-10-6032 The contacts are numbered 1, 2, 3, 4 (but no 5). There's a knurled and slotted screw head on the back that can be unscrewed about 1 turn, maybe to normalizing the pressure inside to match atmospheric. See RT-1185 for a similar application.

USQ-42 Receiver

R-1617A/USQ-46 Receiver

Description

Operation

When powered there is no indication on the front panel that the receiver is working.  Pressing the test buttons to the right of the display will light up each row of digits if the DIM control is clockwise.  If a handset is connected and the SQUELCH is turned down you can hear hissing in the speaker.

GSQ-171

An eBay ad showed the GSQ-171 beside the USQ-46 receiver.  It has what appear to be Vietnamese markings.
What is this: Contact me

TS-2963 Test Set (Transmitter)

PP-6446A/USQ-46 Power Supply (Receiver, Test Set)

Patents, Sonobuoy

1154272 Marine Mine, Emil Senger, Raimund Sauter, Sep 21, 1915, 102/408 -  a plug dissolves after a predetermined time scuttling the mine
1308003 Apparatus for detecting and indicating the presence of submarine boats, G.E. Elia (Italy), June 24, 1919, - raises a flag when sub entangles net
1426337 Signaling apparatus for detecting submarines, Sperry Elmer A, Filed: Jul 9, 1917, Pub: Aug 15, 1922, 455/97, 441/11, 343/709, 174/138.00R, 294/111, 313/553, 114/240.00R, 313/243, 102/402, 174/77.00R, 455/99, 174/153.00R, 343/896, 200/83.00R - when net is entangled by a sub the buoy sends a radio signal
2629083 Expendable radiosonic buoy, Barkson Joseph A, Mason Russell I, Mcnary James C, Filing: Sep 21, 1944, Pub: Feb 17, 1953, 367/3, 343/709, 455/99, 441/33, 441/23, 343/705, 343/901 -
1471547 Production of submarine signals and the location of submarine objects, Chilowsky Constantin, Langevin Paul, May 19, 1917 (W.W.I) Oct 23, 1923
                367/87, 367/174, 89/41.8, 89/41.7, 310/337 - uses the term "ultra-sonorous" 50 kHz to 200 kHz
1426337 Signaling apparatus for detecting submarines, Sperry Elmer A,  Jul 9, 1917, Aug 15, 1922, - triggered by net 455/97, 441/11, 343/709, 174/138.00R, 294/111, 313/553, 114/240.00R, 313/243, 102/402, 174/77.00R, 455/99, 174/153.00R, 343/896, 200/83.00R
2361177 Method and apparatus for the detection of submarines by airplanes, Constantin Chilowsky, Apr 25, 1941, Oct 24, 1944, -
                 367/120, 102/419, 244/137.1, 367/130, 102/427, 434/6
                1829474 Method and device for establishing communication between aircraft in full flight and the ground, Chilowsky Constantin
2397844 Signaling apparatus, Wallace W DeWhurst (RCA) Apr 2, 1946, 367/3, 138/89, 114/198, 455/99, D10/107, 441/11, 73/322.5 - sonobuoy

2402391 Submarine detection, De Witt R Goddard, Rca Corp, Filed: Aug 30, 1943, Pub: Jun 18, 1946, 367/115, 124/51.1, 89/1.51, 367/112, 221/279 -

2420676 Submarine signaling apparatus, Robert E Peterson, Jan 23, 1943 (W.W.II) May 20, 1947, 114/23, 367/150, 114/21.1, 116/27, 181/402, 114/21.3 - uses the term "superaudible frequencies"  

4590590 Sonobuoy Multiple Depth Deployment Apparatus, Magnavox, May 20 1986, 367/4; 441/25; 441/33 -
4727520 Cable Deployment Unit, Sparton of Canada, Feb 23, 1988, 367/4; 367/3; 441/25 -
4901288 Compact cylindrical sonobuoy, Sparton Corp, Feb 13 1990, 367/4 -
4924445 Sonobuoy Cable Pack, Royal Navy, May 8, 1990, 367/4; 114/326; 367/3; 441/8 -
4927057 Automatic Infiltrator for Inflatable Articles, Inflation Tech, May 22, 1990, 222/5; 222/23; 222/41; 222/52; 222/63; 222/93; 222/94; 441/93 -
4493664 Sonobuoy float inflation and depth selection initiators, John R. Dale, Secretary Of The Navy, Jan 15, 1985, 441/7, 441/26, 222/5, 441/30, 367/4, 441/33 -

5076468 Squib Inflator Adapter, Halkey-Roberts Corp, Dec 31, 1991, 222/5; 222/91; 441/93 -
5197036 Sonar Array Mounting for Sonobuoy, Mar 23, 1993, 367/4; 367/153 -
5426617 Long baseline tracking system, Reginald J. Cyr, Secretary Of The Navy, Jun 20, 1995, 367/6 - uses multiple underwater transponders
6400645 Sonobuoy Apparatus, (Navy), Jun 4, 2002, 367/4; 367/3; 367/153 - opens sort of like an 8-sided umbrella

SONAR
3613069 Sonar system, Cary Boyd B Jr, Fenlon Francis H, Gen Dynamics Corp, Oct 12, 1971, 367/92, 367/104, 367/107, 367/101 - combines two Tx frequencies (Mixer Transducer & Pump Transducer- higher SPL), 12, 48 & 60 kHz.    
4320474 Saturation limited parametric sonar source, John M. Huckabay, Reuben H. Wallace, Secretary Of The Navy, Mar 16, 1982, 367/138, 367/92 - phased array?  
4939702 Barrier sonar, Francis J. Murphree, Secretary Of Navy, Filed: Jul 19, 1968(12 year delay) Pub: Jul 3, 1990, 367/138, 367/87, 367/93 -
4998224 System for providing improved reverberation limited sonar performance, Mar 5, 1991
5138587 Harbor Approach- Defense Embedded System, (Navy), 367/136, Aug 1992
5144487 Expendable moving echo radiator, (Navy),  367/1; 367/137; 367/165, Sep 1992 - countermeasures equip
5235558 Choke point bistatic sonar, Harvey C. Woodsum, Joseph J. Stapleton, Gte Government Systems Corp, Aug 10, 1993, 367/92, 367/104, 367/15, 367/908 -

5808580 Radar/sonar system concept for extended range-doppler coverage,
6018493 Sonar Suspension Apparatus, Dowty Maritime Sys, Jan 25, 2000,  367/16; 367/20; 367/153; 367/155; 367/165; 441/33 -

Launching

Photo from Wiki Sonobuoy page

From Ships and Aircraft of the U.S. Fleet (2005):
The P3C Orion. . .  tail-mounted ASQ-81 Magnetic Anomaly Detector (MAD) and 48 external (fuselage) sonolbuoy chutes and four in-flight reloadable (internal) chutes; a total of 84 buoys normally are carried.

Note The

2707904 Sonobuoy Dispensers, Breeze Corp, May 10, 1955, 89/1.51; 367/3 - revolver,
3451306 Safe and Arm Ejection System, Susquehanna Corp, Jun 24 1969, 89/1.1; 89/1.51; 102/259; 102/357 -
3905291 Cartridge-actuated Device and Launching Assembly using same, G.T. Corbin, Sep 16 1975, 102/430; 42/96 -
4026188 Modular Buoy System, Sandars Assoc, May 31 1977, 89/1.51; 102/351; 102/352; 102/354; 102/406 -
4263835 Sonobuoy Launcher System, Navy, Apr 28, 1981, 89/1.51; 89/1.3; 89/1.806; 89/1.818 - bouys loaded from outside
4397433 Revolving-cylinder jettison device for transporting and releasing buoys on and from Aircraft, , Aug 9 1983, 244/137.4; 89/1.51; 89/1.801; 244/118.1 -
5052270 Multi-sonobuoy launch container with constant force spring, Navy, Oct 1 1991, 89/1.51; 244/137.4 -
7278416 Pneumatic projectile launcher and sonobuoy launcher adaptor, Lockheed-Martin, Oct 9, 2007, 124/72; 89/1.51 -

Magnetic Anomaly Detector (MAD) (Wiki)

These were originally called Magnetic Airborne Detectors (Ref 3) and was developed by the NDRC (Wiki) and was paired with the use of sonobuoys.

Maximum range 1 to 2 thousand feet. I'm guessing the range includes the depth of the sub, so the deeper the sub the more likely MAD will miss it.

When I lived in Mountain View it was a very common sight to see a P-3 Orion (Wiki) landing or taking off from Moffett Field Naval Air Station (Wiki).  They had a "stinger" on the tail that held the magnetic anomaly detector.  Here's a Youtube video of the MX-1361/ASQ-8 MAD
It appears to have 3 coils, each about 4" in diameter by 2" thick made by TI mounted in 3 orthogonal directions (X, Y & Z)

The ASA-65 is the motion compensator for the ASQ-81 MAD system.  That's to say that any motion of the P-3 will cause the X, Y & Z components of the Earth's magnetic filed to change.  To back that out three coils can be placed over the magnetic sensors and those coils driven from the output of the ASA-65.

When testing a MAD a small portable "Gamma Slinger" is used that generates a known (1045' c.g.s units) rotating magnetic field.

1045 Gauss converts to 104,500,000 nanotesla.  Since the Earth's field is about 50,000 nanotesla the Gamma Slinger is about 2000 times as strong as the Earth's filed.
It's probably made using a modern permanent magnet rotated on a shaft by a clock work where the shaft and clockwork are all non magnetic.  This test device could be used on the flight line to check out the MAD system.

It can easily be detected at over 20 feet using the ASQ-81.

The AN/ASQ-208 is a digital processing type MAD system.

The ASQ-1, ASQ-1A, ASQ-3 and ASQ-3A  was used in conjunction with the CRT-1 sonobuoy in W.W.II.
Ref pg 302, Chapter 16, SOFAR, Harbor Defense, and other SONAR Systems, Naval Sonar, NAVPERS 10884, 1953

The ASQ-3A was used as the basis of an magnetic survey of the world.
Ref: Airborne Geomagnetic Surveys by the United States Hydrographic Office, Henry P. Stockard, USN Hydrographic Office, NAVIGATION, Journal of The Institute of Navigation, Vol. 4, No. 8, 1955, pp. 320-323. modified to use the Vector Airborne Magnetometer type 2A (VAM-2A)

NOL vector airborne magnetometer type 2A (VAM-2A)

The Pave Mace system that used the Black Crow MAD sensor was optimized to pickup the magnetic filed from ignition system in Vietnamese vehicles.  (link to external web page with photo of it).  The plate to the side of the dome with 3 rows of holes along the top and 3 more rows of holes on the bottom has the feel of a slot antenna for VHF or UHF signals, so more of a radio system than a MAD system.  If you have any definitive information let me know.
It's not clear if this is a magnetic system or a VHF/UHF radio system.

Magnetic Anomaly Detector (MAD) Patents

2361177 Method and apparatus for the detection of submarines by airplanes. Constantin Chilowsky, Filed: 25 Apr 1941, Pub :24 Oct 1944, 367/120, 102/419, 244/137.1, 367/130, 102/427, 434/6 - Referenced by 35 patents - not MAD by rather audio
2406870 Apparatus for responding to magnetic fields, Vacquier Victor V,  Gulf Research Development Co, filed: Jul 21, 1941,

324/253, 102/417, 33/361, 318/647, 324/326, 324/345, 324/255, 340/870.33, 102/427
This is THE MAD patent and is referenced by a very large number of others.

The following detectors are towed on a cable from a plane flying at 300 feet above the water:
2379447 Antisubmarine device, Lindsey Henry A D, Jul 3, 1945, 102/417, 102/212, 340/551, 324/247, 324/67, 307/652, 324/258, 340/552
2404806 Submarine detector, Lindsey Henry A D, Jul 30, 1946, 340/850, 102/402, 324/247, 324/331
2424772 System for detecting magnetic masses, Frank Rieber, Interval Instr Inc, Jul 29, 1947, 324/247, 324/331, 322/1, 324/257, 322/59, 340/870.32
2549857 Cable-suspended aerodynamic body, Schonstedt Erick O, Apr 24, 1951, 324/260, 324/262, 114/24, 244/3, 74/5.00R, 324/331, 324/246, 33/397, 33/366.11
2632884 Orienting mechanism for magnetic detector devices, Murphy Paul M, Mar 24, 1953, 324/253, 318/647, 324/246, 324/331
2696602 Compensated magnetometer, Richard Evans Chauncey, Dec 7, 1954, 324/253, 324/345 - uses term "magnetic anomalies"

SONAR Countermeasures

You see this in movies like The Hunt for Red October or Crimson Tide.
3771115 Simulated submarine target apparatus, McLinden Hugh,    - a viscous, gelatinous  material having metalic particles suspended in it, is ejected by the sub to form a hollow bag-like structure which is filled with water.
2901997 Sound generator, Arthur H Brooks, Sep 1, 1959 (14 year delay), 116/27, 116/137.00R, 102/418, 367/1 -  
3194207 Underwater sound sources, Dunne Brian B, Gen Dynamics Corp, Jul 13, 1965, 116/27, 367/142 - alectric motor driven noise maker + flotation device, cylindrical shape (torpedo tube or smaller?) 
4194246 Noisemaker beacon, Ralph P. Crist, Secretary Of The Navy, Mar 18, 1980 (32 years delay), 367/1, 441/22, 441/12 - 10 to 100 kHz output
5117731 Tactical acoustic decoy, Mark A. Mendenhall, Secretary Of The Navy, Jun 2, 1992, 89/1.816, 102/348, 367/1, 102/501 - mounts on ship and jamms infrared, sonar & microwave.
6252822 Countermeasure device with air bag hover system and pressure compensated acoustic projectors, Robert J. Obara, Secretary Of The Navy, Jun 26, 2001, 367/1 - uses compressed air for both depth control and noise making   

Maybe called sonar counter counter measures was a type of sonar that was difficult for an enemy to hear.  

Hydrophone

A hydrophone (Wiki) is an underwater sound sensor.  On purpose I did not call it some type of microphone because that would imply it can only respond to sound within the frequency band which human ears can hear.  So, I think, sensor (Wiki) or transducer (Wiki) are better terms to use.  The key reason for that is most SONAR (Wiki) involves ultrasonic frequencies.

An early piezo electric material used for  hydrophones was Rochelle Salt (Wiki) which can be made from ingredients from the grocery store using instructions from YouTube.  Since it's water based, getting water on the crystal will dissolve it, so maybe not idea for an underwater application. Barium Titanate (Wiki) is another piezoelectric (Wiki) material used for hydrophones.  Although know in the W.W.II time frame, Titanium was not readily available in war time, so Magnetostriction (Wiki) was used for hydrophones early in W.W.II, like used on the CRT-1 sonobuoy.
See my Magnetics web page for an example of Terfenol-D material.

Got this hydrophone from Fair Radio.  It consists of a bladder just under five feet long and about three inches in diameter filled with mineral oil (or something similar).  Inside there are eight cylindrical  Rochelle Salt Crystal doublets, each about three inches long with about a three inch gap between sensors (series or parallel connection?). 

In the Combat Information Center magazine for July 1944 (Vol. 1 No. 5) there's an article on harbor defense that mentions both a sonobuoy with vertical hydrophone array (radio has 12 mile range and hydrophone has 1,000 yard range) as well as multiple hydrophones laid on the bottom and connected to multi-conductor cable.

At the cable end of the hydrophone is a matching transformer with 25 Ohm output impedance.  Frequency response of 1Hz to 20 kHz (i.e. young human hearing range).
The internal construction seems to be steel cylinders spot welded to two steel rods that tie them toghther.  The crystals are glued into the cylinders and wired in parallel.
If buried in the ground as is the mineral oil will leak out leaving air voids.  If repackaged in a PVC pipe the sound would travel up and down the pipe wall which doesn't happen with the current rubber bladder.  So maybe some type of flexable hose would be a good replacement? 

The idea is to bury it and have excellent low frequency (below 20 Hz) response.  The Infra sound sensors use garden hose with a pin hole leak.

Official Description:

Hydrophone, U. S. Navy Harbor Detection, Sonic, NT-51038F; P/O type JR-1 Harbor Detection Equipment. Sensitive listening, frequency range 1 - 20 thousand cycles per second; with 8 Rochelle Salt Crystal Doublets each approx. 3" x 2" x 1", in metal frame w/matching transformer to 25 ohm line, in Castor (?) Oil, encased by heavy rubber jacket 56" long x 2 1/2" in diameter; with 9 foot rubber covered cable 1/2" O.D. w/2 flexible copper wires insulated, plus 2 steel strain wires; to be used down to 400ft. depth while withstanding high pressure explosion waves.  Mfg by Brush Development Company.

How can the transformer work over that frequency range? 

3 Feb 2012 - When the 999 average spectrum plot finishes I'll have a look at the impedance.

Fig HP1	Fig HP2 Transformer
White Red Black Green Blue Case Ground White  - Opn Opn  Opn  Opn Red - -  Opn  Opn  Sht Black - - - Sht Opn  Green - - - -  Opn Blue - - - - - The Red and Blue terminals are physically in line. The Black and Green terminals are physically in line. The White wire is not an electrical connection but rather is where a couple of steel cables attach for supporting the weight of the hydrophone. It's not clear what this is.
HP 4395A Plot 1 Hz to 20 kHz RBW: 1 Hz, True RMS detection, 16 averages:	HP 4395A Plot 1Hz to 20 kHz RBW: 1 Hz, True RMS detection, 999 averages (54.6 hours):
HP 4395A Z transform Impedance Real & Imaginary	HP 4395A Z transform Hydrophone Impedance Smith Chart with Marker List

2631271 Tubular hydrophone, A.L. Thuras (New London, CT),  Sec of Navy, Mar 10, 1953, 367/168 -  CRT-1 
4965778 Helical magnetostrictive core line hydrophone, David E. Parker, Markay Malootian, Secretary Of The Navy, Oct 23, 1990 (21 year delay), 367/168 -   

Brush Development Co. Patents

Their early work with Piezoelectric devices (Wiki) was for microphones and speakers used in air.

1906758 Crystal and method of producing the same, Kjellgren Bengt, Brush Dev Co, May 2, 1933, 117/69, 117/68, 117/926, 252/1, 562/580 - Rochelle salt - but the methods seem the same as used today for silicon or any other crystal.
2105010 Piezoelectric device, Baldwin Sawyer Charles, Brush Dev Co, Jan 11, 1938, 381/190, 310/331, 367/164, 601/2, 367/161, 381/173 - Rochelle salt disk or plate or stacks or grids of them, mike or speaker
2126437 Apparatus for generating electrical waves - tubes
2269403 Piezoelectric unit - loudspeaker for use in air (for similar loudspeaker see: LS-685/U Crystal Loudspeaker)
2413462 Transducer, Massa Frank, Brush Dev Co, Filed: Jul 30, 1942, Pub: Dec 31, 1946, 367/157, 310/340, 381/190, 310/337, 310/362, 367/163 - early hydrophone (no projector function)  
2440903 Underwater transducer, Massa Frank, Brush Dev Co, Filed: Jan 6, 1944, Pub: May 4, 1948, 367/160, 381/190, 381/163 - "piezoelectric and magnetostrictive transducer devices adapted to function underwater either as a microphone or as a loudspeaker."  38 patents reference this one     

Roswell Connection

While studying the MH370 disappearance and search (March - April 2014) and in particular the 37.5 kHz ultrasonic pings from the Cockpit Voice Recorder (Wiki: CVR) and the Flight Data Recorder (Wiki: FDR) generated by the Underwater Locator Beacon (Wiki: ULB).  This lead to the SOFAR channel (Wiki) and the thermocline (Wiki).  A way to determine the depth of the thermocline is to drop an SSQ-36 (see SSQ-36 above) or other Bathythermograph such as the SSXBT (Wiki: BT).  Note that the maximum depth of the SSQ-36 is 800 meters, not the center of the SOFAR channel which might be at 1000 meters, but low enough to be in the channel. 

2587301 Method of sound transmission, Ewing William M, (Wiki), Us Navy, Filed: Nov 16, 1945 (7 year delay), Pub: Feb 26, 1952, 67/127 - "sound channel" , Fig 7 map showing listening staations: Aleutian Islands, Kurie Islands, Marinas, Saipan Islands & Midway.  Explosion set for 675 fathoms.
2601245 Underwater signaling device, Charles F Bowersett, Filed: Jan 30, 1948, Pub: Jun 24, 1952, 181/142, 102/229, 181/125 -  contains explosives 
2760180 Long range explosive sonobuoy, George Sipkin, Filed: Oct 6, 1949, (7 year delay), Pub: Aug 21, 1956, - explains sound channel

It turns out that a stock sonobuoy can not hear the 37.5 kHz ULB since the highest frequency they can hear is 20 kHz (see DIFAR above).  So a stock sonobuoy can not be used to find the CVR or FDR.  But all the information about sound propagation in water is applicable to normal sonobuoy operation.

Note that military passive SONAR (Wiki) is designed to pick up the sounds generated by surface ships, submarines and torpedos (maybe 10 Hz to 20 kHz), not aircraft black boxes at 37 kHz.  This frequency range does include a lot of sea life so a sonar man needs to know what they sound like, or his computer knows.   If you rub your thumb and index fingers together you generate an ultrasonic sound, like that used by Bats, in the 30 kHz region but no normal audio.

Maurice Ewing (Wiki) who discovered the SOFAR channel (Wiki) figured out that the speed of sound vs. depth would cause sound to be "piped" if it was in the SOFAR channel rather than being omnidirectional if not in the channel.  He extrapolated that idea to the atmosphere where the speed of sound vs altitude curve has the same shape as the one for speed of sound vs depth in water and so there should also be an atmospheric channel ( it turned out to be at about 50,000 feet whereas the ocean channel is at about 1000 meters deep).  By putting microphones (in the 1940s the state of the art microphone technology was the Disk Microphone (used by Orson Wells - Wiki), or disk for short like we now say radio instead of Radio Receiver) in the channel you can hear sounds from very very far away that you can not hear any other way.  Disk microphones are called "spring microphones" on eBay.  For example rocket launches or atomic bomb testing.
Richard Muller Physics Lecture 11 - Waves 1 
Wiki: Sofar bomb

Then I watched the UC Berkeley Physics 10 - Lecture 11: - Waves I (YouTube, Text)  by Richard Muller (Amazon).  It turns out that the Project Mogul (Wiki 1947 - 1949) used the bulk of a CRT-1 sonobuoy.  They replaced the hydrophone with a string of "Disk Microphones" that was 657 feel long.  He also mentions SOSUS and "Hunt for Red October" in passing.  The SOFAR bomb was used by W.W. II pilots downed in the ocean.  They would throw this hollow metal sphere (SOFAR bomb aka: SOFAR Sphere (Wiki)) into the water and it would sink.  After about 5 minutes it would reach about 1000 meters depth and implode.  The implosion had the energy of about 2 pounds of TNT.  The shore based SOFAR stations would note the time of arrival and triangulate the location of the implosion.  Later the Signals (underwater sound) Mk 22 Mods 0 and 1 were developed to work with the shore stations.  If an enemy captured one of these SOFAR bombs and cut it open it would be very unlikely that they could determine what it was or how it was used.

When Project Mogul flight No. 4 crashed outside Roswell the Air Force reported that "flying disks had been recovered" from the wreakage, but the local paper reported it as a "RAAF Captures Flying Saucer".  Note the change from plural because there were a large number of disk microphones to singular Flying Saucer".
See my Western Electric 387W Disk Microphone web page for an example of a disk microphone.  Note eBay search term "Spring Microphone".
The Wiki page Roswell_UFO_incident - has an image from the Roswell Daily Record, July 8, 1947. The main headline is: "RAAF Captures Flying Saucer On Ranch in Roswell Region".  The subheading is "No Details of Flying Disk Are Revealed". 

This web page was started because of the connection to Vietnam era seismic detectors (outdoor intrusion alarms).  But I still have not determined which sonobuoy was the source for the 2-3/4" diameter cylindrical components of the GSQ-160, if you know please tell me.

In the official Air Force book "The Roswell Report - Fact vs. Fiction in the New Mexico Desert - Headquarters United States Air Force - 1995 - ISBN 0-16-048023-X (free on line as roswell.pdf) - 993 pages see attachment 32, "Report of Findings on Balloon Research", chapter Project MOGUL, pdf-Pg 303 that describes the underwater sound channel and the idea by Dr. Maurice Ewing (Wiki) that there might also be a sound channel in the atmosphere and how to exploit that idea as Project Mogul (Wiki).

A Google Patents search on inassignee:"Gen Mills Inc" balloon will turn up many patents related to the new type balloon good for high altitude
2526719 Balloon construction, Winzen Otto C, Gen Mills Inc, Apr 2, 1948 - key is replacing rubberized fabric with polyethylene (Wiki)
2492800 Fast rising sounding balloon, Isom Langley W, Aug 16, 1948 - key non elastic material.

In the book An Ocean in Common: American Naval Officers, Scientists, and the Ocean Environment (Ref 4) they mention that the sound channel in the Atlantic ocean is 4,000 feet but in the Pacific it's at 2,500 feet. (page 173).

Unknown Sonobuoy - What is it?

There are many similarities with the CRT-1, but . . .
It looks like mid 1960s (date code, TO-3 power transistor in power supply, 1xx and 3xx tubes).
Someone has scratched SONOR on one of the sheet metal covers with an arrow pointing down.  This implies it's an active pinging unit rather than a passive listening only unit.
That it reinforced by the large space for batteries.
This is not mine.  Photos and information supplied by Michael, VK4ZKT

UnKS Fig 1

UnKS Fig 2  Tubes may be 12AT7, not low voltage like in the CRT-1.

UnKS Fig 3

UnKS Fig 4

Underwater Communications

6856578 Underwater alert system, Daniel J. Magine, Kevin D. Kaschke, Feb 15, 2005, 367/134 - Ocean Technology Systems Diver REcall System DRS-100?

Submerged Signal Ejector (SSE)

aka: Submerged Signal and Decoy Ejectors (SSDE)

Maritime.org - 12-4-01 Submerged Signal Ejectors  - 6" internal diameter:

These are similar to 100mm diameter torpedo tubes are probably are located in torpedo rooms.  These tubes can be used to launch various devices that fit the 100mm (4") tube.
Countermeasures, emergency beacons, signal flares, small explosive charges and probably a Bathythermograph (would require a way to handle the trailing wire) . . .
T-347/SRT Submarine Rescue buoy that transmits SOS SUB SUNK SOS is about 3-1/4" dia x 40-1/2" long and can be launched using the SSE.

Ref 8 mentions a 3" signal/decoy ejector (pg 69 photo of Bathythermograph & its terminal) that can be used for the Submarine Launched One-way Transmitter (SLOT)(pg 70).  In the Glossary (pg 308) "usually 3-inch".

So are there two different small launch tubes, i.e. 3" and 4" or has one of these become a standard? let me know

	2710458 Underwater acoustic decoy, Reed Donald G, Sec of Navy, Filed: Jun 14, 1945 (10.0 year delay), Pub: Jun 14, 1955, 434/6, 114/20.1, 367/1, 434/25 - passive SONAR training device Fig 1: either 3x32" or 4x43", most likley 3x32" Fig 9: either 3x24 or 4x32" This may or may not be launched from a sub.
	2981927 Underwater sound transmitter, Vaughn G Mckenney, Sec of Navy, Filed: Apr 4, 1946 (15 year delay), Pub: Apr 25, 1961, 367/1, 455/18, 114/20.1, 360/6 - returns SONAR pings at same frequency but offset in time (very similar to RADAR countermeasures). Fig 1 shows a length/diameter ratio of 11.5, so if 3" dia then length is 34", if dia is 4" then length is 46". Since a yard or meter shows up as a practical length then I'd assume this is a 3 x 34" device. Mentions: 2793589 Buoyancy control device, Atchley Raymond D, Filed: May 3, 1944, (13 year delay), Pub: May 28, 1957, 102/414 -
	5003515 Submarine emergency communication transmitter, Albert S. Will, Frank C. McLean, Sylvan Wolf, Samuel H. Kauffman, John C. Hetzler, Jr., Charles A. Lewis, George E. Maxim, Secretary Of The Navy, Filed: May 28, 1964, (27 year delay)    Pub: Mar 26, 1991, 367/131, 367/145 - Image flipped so that it's oriented as if in the water.  There are 7 drop bombs which are released by explosive bolts and they explode after 20 seconds so that their depth will be controlled (probably within the sound channel (see Roswell Connection above).  If the sink rate was the same as the Mk IX depth charge (15 fps) then after 20 seconds it would be down to 300 feet which is too shallow to get into the SOFAR Channel (Wiki).  I suspect the time delay is really much longer to that the drop bombs get into the SOFAR Channel. The timing of the drop bomb release translated into one of a number of coded messages. The length/diameter ratio is very small so will not help to determine its dimensions.
	5044281 Submarine flare with vertical attitude determination, Peter Ramsay, Brian W. Whiffen, Gerald M. Bushnell, Victor Nanut, Robert C. Czigledy, Robert J. Swinton, Maxwell J. Coxhead, Timothy R. Clarke, Australia, Sep 3, 1991, 102/340, 102/224, 102/351, 102/357, 102/354 - The length/diameter ratio is 12.67, so: 3" x 38" or 4" x 57", seems to indicate it's 3 x 38".

Related

Books

YouTube

ASW To Catch a Shadow - Anti-submarine Warfare, P-3 Orion, USS Scorpion 20850 HD - 29 minutes
Goblin on the Doorstep - ASW Anti-submarine Warfare 20870 HD - 29 minutes -Collecting microscope slide from early Bathythermograph,
ASW: Tracking the Threat 1982 US Navy Training Film; Anti-Submarine Warfare - 23 min - Launching Bathythermograph -

BT data after launch of BT

U.S. NAVY SONOBUOY INDICATOR GROUP AN/AQA-1 ANTI-SUBMARINE WARFARE FILM 51114 (28:53) -  17.5 minutes @2:16: ANB-H-1 Headphones -

Works with:
R-316A Dual receive channel sonobuoy receiver - 16 frequency channels
 ARR-26
SSQ-15 Range only (sends out pings every 5 seconds)
SSQ-20 DIFAR
SSQ-2b non-directional (Explosive type)

U.S. NAVY MK-84 SONOBUOY TRAINING FILM SIGNAL UNDERWATER SOUND (SUS) 81204  - 12 minutes - Sound Underwater Signal Mk 84 Mod 0. Non Explosive,  can be set to one of 4 preset codes. 2.95 & 3.55 kHz: can be heard with: AN/BQR-2, AN/BQR-7, AN/UQC underwater telephone on the third harmonic (aprox. 10 kHz)
Coordinated Anti-Submarine Warfare - SONAR, Sonobuoys, USS Stein, USS Badger 20890 HD - 19 minutes - about fleet operations
ASW The Submariners - USS Shark, Anti-submarine Warfare Maneuvers 20800 HD - 29 minutes - @12:22: USS Holland First US sub
Hunter Killer Anti-Submarine Wwarfare U.S. Navy Film 30102 - 21 minutes - Edward R. Murrow (Wiki) - Prop planes
Blind Man's Bluff - History Channel Documentary - 1hr 35min - Some factual errors, see: SOSUS
HD Historic Stock Footage AERIAL ANTI-SUBMARINE WARFARE - @4:34 MAD chart output,
The Guide To Submarines Documentary - welldone
Inside a Navy anti-Submarine Lockheed P-3 Orion Aircraft - Moffett Field Museum -14 -
Visualizing Humpback Whale Calls using DIFAR Sonobuoy -
Modern Sonar Sounds and other Sounds of the Sea - LOFAR
Lockheed P-3 Orion Training Mission- Part 1, Part 2 -
P-3 Orion 50th Anniversary -
Project Tinkertoy (IC Precursor) 1953 US Navy; Automated Manufacturing of Modular Electronics - @4:43 shows Sonobuoy (or?)-

Links

page created 22 Oct 20112