Detecting-Transmitting Set, Electromagnetic

Brooke Clarke 2000 -2022

GSQ-160 Outdoor
                Intrusion Alarm
GSQ-160 Outdoor
              Intrusion Alarm Bottom, sonobouy cylindrical parts
Web Page Summarizing Intrusion Detectors and Related Equipment

Key Components

BA-1549U Battery
MX-8846/GSQ-160 Detecting Transmitting Set Sub Assembly
A1 Sensor Oscillator
A2 Supplemental Circuits
A3 2.5 MHz Signal Processor
A4 Secondary Processor
A5 Antenna Coupler
A6 Electrical Chassis
A7 Data Transmitter
TC432 Code Plug
TC431 Encoder
TC-560 Transmitter
    Atlas MMS Explosive Charge
AS-2542/GSQ-160 Antenna
Related Equipment
USQ-46 (USQ-46A) Radio Frequency Monitor Set WANTED TO BUY
TS-2963/USQ-46 Test Set
PP6446A/USQ-46 Power Supply
Battries for USQ-46 & TS-2963
ID-1721 Indicator WANTED TO BUY
PT1561 Code Plug Programmer
PT1586 Stack Tester
GATE  General-Purpose Automatic Test Equipment
Similar Equipment
GSQ-154 Alarm Set, Anti Intrusion, Restricted Area - seperate web page
Plant Antenna -
Contelco-Guard ME-400
TRC3- Photo -
PEWS - Photo of PEWS trasmitter Does this transmit a code that the USQ-46 receiver can understand?
GSS-26 -
Other Manuals


Fig 1 top view
GSQ-160 outdoor
                intrusion detector
Fig 2 Illustration from manual
GSQ-160 outdoor
                intrusion detector


This is a battery powered set designed to be buried with the antenna and daylight sensor above ground.  It detects changes in it's RF field at 60 & 57.5 MHz and will transmit an alarm around 168 MHz when it detects a change above some threshold.  I think that not only will it detect people (or large animals) at about 120 feet and also vehicles at longer ranges but also any radio transmissions that might impair it's operation.
The date codes are for the early 1970's.

There is a label on the top that says:

DATE    MAR 81
The Surveillance Systems Directorate has jurisdiction for sensors.  They are in Pennsylvania.

Key Components

Main Electronics sub-assemblies
The main electronics are contained in the top half of the case.  The lower half holds the battery.

BA-1549U Battery - Battery Box CY 7046/GSQ-160

The battery box is just the lower half of the GSQ-160 case.
Has the following outputs: Since the batteries are hard to come by and the connector is not one I know, I plan to use some of the unused pins on the GATE DB25m connector for power.  Both the GATE connector and Plug 1 are on the A6 motherboard.
Pin 12 will be -4 VDC - to A6 Green wire
Pin 13 will be +4 VDC - to A6 Blue wire
Pin 25 will be +30 VDC - to A6 Orange wire
Fig 3 Battery Plug P1 schematic
GSQ-160 outdoor intrusion detector battery
                  plug schematic

MX-8846/GSQ-160 Detecting Transmitting Set Sub Assembly

The top half case has a 6 pin male plug that goes into the battery.  There is a center pin with a flat and 6 smaller pins.  Two of the smaller pins are ground contacts, but I have yet to determine which pin is what voltage. Drawing showing battery connector, tamper switch, GATE DB-25m. (You need the Free Volo or WHIP! Viewer from Autodesk). 
Fig 4 Bottom View
GSQ-160 outdoor intrusion detector
Fig 5 Chassis Removed
GSQ-160 outdoor
                    intrusion detector
Fig 6

A1 Sensor Oscillator

This board contains two oscillators, one at 60 MHz and another at 57.5 MHz.  They drive the antenna with about 1 milliwatt of power.  These signals provide the EM field that detects changes in impedance.
This is NOT a seismic or magnetic detector, but rather an Electromagnetic filed based detector (Wiki).

There is also a mixer that combines the transmitted and received signals to produce a 2.5 MHz output.

A2 Supplemental Circuits

There are functions for:

A3 2.5 MHz Signal Processor

This analog circuit does some primary signal processing on the 2.5 MHz signal.

A4 Secondary Processor

Does log, filtering and anti-log operations and generates the alarm pulse.
A mute pulse also generated that is used to shut down the 57.5 & 60 MHz transmitter as well as stop signal processing during an alarm.

A5 Antenna Coupler

This is really a diplexer that allows the 60 & 57.5 MHz sensing RF go to the antenna and also allows the 162 - 174 MHz alarm transmission to also go to the antenna.  A5 is part of the Plate with 3 screws
Note "G-7 Recovery code stenciled on bottom.
GSQ-160 outdoor
            intrusion detector

A6 Electrical Chassis

Contains the Off - Test - Arm switch, the daylight sensor, the two recovery code switches and a motherboard for the other modules to connect to each other.

To remove chassis from top half:

There is also a DB-25m connector (A6J5) that is for use with the GATE test equipment. In the Photo you can see the tamper switch on the left, the cylindrical tilt switch "A5" and A6J5 connector.
GSQ-160 outdoor
            intrusion detector
The Battery Connector has 6 male pins.  The longer bigger center pin has a flat.
When looking at this connector with the flat down:

A7 Data Transmitter has 3 modules

                    outdoor intrusion detector
This consists of three parts.  These parts are not covered in the manuals for the AN/GSQ-160 and are used in other military equipment.  These parts all are cylinders 2.75" in diameter and all have a common connector that is a ring with 92 pins and 4 coaxial connectors that are 90 degrees apart labeled A, B, C and D (not part of the pin numbering system).  There are 4 versions of this connector here:
  • TA383 both male and female pins and the module is just under an inch long
  • TA385 has only male pins like on the transmitter Male End
  • TA386 has Female pins and wires going to the GSQ-160 or other equipment

 I think that this connector system was developed by Sandia.  In the case of the TA385 combined male and female connector that all the pins go straight through (I will check this).  If that's true then maybe you can install these 1" high modules in any order.  They would take their power form known pins and send their outputs to pins that were only used for that purpose.  More on this after some Ohm meter work. Table showing 92-pin wiring for the 3 cylinders.

25 Sep 2002 - I now think this is the same modular system used to build sonobuoys.  The frequency range of the transmitter matches the assignments for sonobuoys.

TC432 male end
GSQ-160 outdoor intrusion detector
34372, ODE PLUG
S/N 01492
MAR 71

with hand written Label:
 231 14 00 34
on the circumference of the cylinder
TC432 female end
GSQ-160 outdoor intrusion detector

TC431 male end
GSQ-160 outdoor intrusion detector

TC431 female end
GSQ-160 outdoor intrusion detector

TC-560 male end
GSQ-160 outdoor intrusion detector
S/N   A03778
CHAN 442
TC-560 female end
GSQ-160 outdoor intrusion detector

AS-2542/GSQ-160 Antenna  WANTED TO BUY

I would like to get one of these.  It's a dual mode antenna with a type-N(m) connector at the base.  The A5 Antenna Coupler drives either the outer conductor or the center conductor of the type-N(f) connector depending on the frequency and the antenna works in different modes for 57.5/60 MHz and for 168 MHz.  It is designed with a slight bend so as to look like a plant.

The top section is 32" and the bottom 14" for a total length of 46".


Army TM 11-5840-352-14
Air Force TO 31S9-2GSQ-160-1
Electromagnetic Detecting-Transmitting Set AN/GSQ-160
Simulator Group OA-29/GSQ-160
(FSN 5840-168-7719)
March 1972
Operating Instructions and direct support. Includes detailed functional description.

TM 11-5840-352-24P
Detecting-Transmitting Set, Electromagnetic AN/GSQ-160
(NSN 5840-00-168-7719)
Simulator Group OH-29/GSQ-160
(NSN 6625-00-482-6150)
Current as of 1 February 1978
Repair Parts designations and lists.

Related Equipment

R1617/USQ-46 (USQ-46A) Radio Frequency Monitor Set 

TS-2963/USQ-46 Test Set

PP6446A/USQ-46 Power Supply

ID-1721 Indicator WANTED TO BUY

PT1561 Code Plug Programmer

T.O. 31S9-4-18-1
TM 11-6625-2514-14-2
Code Plug Programmer Test Set
Model PT1561
Part No. 336467-000
This copy is a reprint tht includes current changes 1 through 3.
15 February 1971
Change 1 10 April 1973
Air Force 7-8-73 - 250 Reprint

PT1586 Stack Tester

AF T.O. 31S9-4-20-1
System/Stack Tester
Model PT1586
Part No. 286823-000
This copy is a reprint tht includes current changes 1 through 5.
15 February 1971
TM 11-6625-2514-14-1
The PT1585 is a tester for use with a stack of the 2.75" diameter components.
The MA31, MA33, MA37, MA124, MA133 (AUDET), MA134 (EDET), MA135 (AUDET), MA136(EDET), MA137(Sesmic), MA138(Seismic AUDET) , MA139(Seismic EDIT) sensors and MA56, MA87, MA88 EXRAY's or completly assembled sensors or EXRAY's can be tested.  This includes the CADET family of sensors. Some of the sensors are: Hi-rise refers to a rocket powered stack.

MA31 is a Command Link (CL) sensor containing 9 modules
consists of: TC437, TC431, TC432, TC430, TC436, TC433, TC434, TC460

MA125, MA135, MA137 and MA133 are ground CL sensors with 10 modules
MA124 and MA133 are CL hangup sensors with 8 modules
MA33 and MA37 are Non-CL sensors with 5 modules:: TC431, TC432, TC434 (less TC437)
MA134 (5 modules), MA136 (7 modules) and MA139 (7 modules) are NCL sensors
MA56, MA87 and MA88 EXRAY's are expendable relay sensors with 6 modules

The L module may be the TC432 Code Plug
The T module is the Transmitter
The E module is the TC431 Encoder
order of remaining modules: E L Z J S R T V wires from the V module.

GATE General-Purpose Automatic Test Equipment

This was a Generic Automatic Test Equipment system based on the HP 2116 computer (core memory), paper tape reader and a lot of equal vintage HP test equipment.  In this way you could automatically measure common parameters like voltage, resistance, frequency, power, etc.using an adapter that connected the device under test with the test equipment.  By measuring the voltages on the GATE connector you will be measuring Test Point voltages (or frequency, resistance, etc.).

Other Manuals

All of the above  Technical Manuals are available on line at LOGSA.

If you have either of the below manuals contact me.
TM 11-5985-385-14&P Title?
065241.pdf -classified

TM 11-5821-356-23RADIO SET AN/ARC-164 RADIO RECEIVER-TRANSMITTERS RT-1145F, RT-1167, RT-1167A, RT-1167B, RT-1167C, RT-1167G, RT-1167H, RT-1504, RT-1518, RT-1518A, RT-1518B, RT-1518C, AND RT-1614 RADIO SET CONTROLS C-9682B AND C-11721 ELECTRICAL EQUIPMENT MOUNTING BASES MT...

074680.pdf -classified

Plant Antenna

Rubber coated with "branches" that are not an active part of antenna.
Need to measure the VSWR to see if it would work on the GSQ-160.
 Vietnam era Plant

Contelco-Guard ME-400

This is probably a 432 MHz Doppler sensor.  By visual inspection it's a two transistor oscillator on the center PCB coupled to the bottom (reference) and top (Antenna) PCBs.  A diode is connected from both the top and reference boards to the output through an RC filter.  The output will be a low level audio spectrum.

The top PCB is marked:
it also has pads that would allow installing the sampling diode on the PCB, but the diode is installed by using insulating sleeving over the diode lead through a hole in the shield.

The red wire is probably the positive power and the black wire the power return.

Since wavelength in meters is 300/Freq (Mhz) this unit works where a half wave is about 14 inches, considerably smaller than a human.  It appears to be in the 70cm ham band (Frequency Assignments).


Justice Technology Information Network - Perimeter Security Sensor Technologies Handbook, 1997 -
Army Physical Security Equipment (PM-PSE) Newsletter 1Q2000- they are upgrading a number of bases which are named
GSQ-151 - a seismic detector
GSQ-187 - REMBASS detector
DT-561(A)/GSQ  hand-emplaced, magnetic detecting sensor.
DT-562(A)/GSQ. This is a hand-emplaced, SA classifying sensor. It detects targets and classifies them as unknown, wheeled vehicle, tracked vehicle, or personnel.
DT-565(A)/GSQ. This is a hand-emplaced, passive IR detecting sensor
Radio Repeater, RT-1175(A)/GSQ
Monitor/Programmer, AN/PSQ-7
Advanced Monitoring Display System . (AMDS)
Batteries. The sensors, repeaters, and M/P use either BA-5557/U lithium or AA alkaline or nicad
 The REMBASS set uses the AN/GSQ-187 to relay data.
AN/PSR-1 Model X-150A - on my Sensors web page
MARINE CORPS ORDER 1510.64A - with equipment list:
                               Appendix A to ENCLOSURE (5) 5-A-1  MCO 1510.64A 25 MAY 1994

                              TRAINING EQUIPMENT

RO-376A-USQ        Signal Data Recorder
AN/USQ-46A         Portable Monitor
AN/GSQ-159         Disposable Seismic Intrusion Detector
AN/GSQ-154A        Miniaturized Seismic Intrusion Detector
  DT-383/GSQ         Audio Add-on Unit
  AN/GSQ-171         Directional Infrared Intrusion Detector
  AN/GSQ-176(S)      Air Delivered Seismic Intrusion Detector (Short)
  AN/GSQ-176(N)      Air Delivered Seismic Intrusion Detector (Normal)
  AN/USQ-66(V)       Battlefield Area Surveillance System
  TS-2963/USQ-46     Emission Generator
  AN/GRQ-21          Expendable Relay
  AN/GRQ-26          Receiver-Transmitter
  AN/GXQ-257     Unattended Ground Sensor Set
  AN/MSC-77          Sensor Mobile Monitoring System
  M1097              High Mobility Multipurpose Wheeled Vehicle
  AN/USQ-126     Sensor Monitoring System
  RO-630/USQ         Signal Data Recorder
                     SMS Antenna Group
                     SDR Remote Kit
                     Communications Group
  RE-1162/U          Relay Assembly
                     Relay Unit
                     UHF Assembly
                     Battery Box
                     Relay Assembly Antenna Support Kit
  AN/USQ-121     Portable Monitor
                 Test Set, TRSS

GSS-26(A) Alarm Set, Anti-Intrusion Restricted Area - After opening this hermetically sealed can I found no sensors.  There are 3 double sided printed circuit boards, 1975 date codes, high Q analog caps and inductors and what may be IC type op-amps.  I would say this is some type of analog processing circuit, maybe an "Audio" based alarm.  There are 3 connectors, maybe Power, Microphone input and Connection to rest of alarm system?

TM 11-6350-200-10 is on the ETM page, but is restricted.


2545503 Radio object detection alarm, William Tucker, May 30, 1945, Mar 20, 1951, 342/28, 340/539.17, 340/539.1, 367/112, 340/552 - Doppler sensing
3750162 Alarm system, Seaton W, Garside Corp, Jul 31, 1973, 342/28, 340/501, - maybe Fig 6 is the ME-400?
4026188 Modular buoy system, Thomas E. Woodruff, Roger I. Saunders, Lockheed Sanders Inc,  1977-05-31,
89/1.51; 102/352; 102/406; 102/351; 102/354 - a single tube holds a few sonobuoys which can be launched one at a time.

Mike Murphy Surplus - my source for much of the above
Fair Radio Sales - also had some printed manuals that were not on LOGSA  for info on using LOGSA see my manuals page

Brooke's PRC68 . alphanumeric index to web pages, Products for Sale, Contact

[an error occurred while processing this directive] page created 22 July 2000.