Detecting-Transmitting Set, Electromagnetic

TCnnn Modules

Brooke Clarke 2000 -2023

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

GSQ-160 Overview
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.
14 April 2023 - After learning about Sonobuoys it think they need to be light weight, like Radiosondes, and the TCnnn series of modules are very heavy so would not be used in Sonobuoys because of their heavy weight.  The ADSID is noticeably heavy.

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.

ADSID "HIT Assembly"

This is an acronym for Air-Delivered Seismic Intrusion Detector (Wiki).  This unit can not be air delivered, but may be a support device, like a repeater?

See Sonobuoy Ref 11 Wiring Vietnam -
Display of A.D.S.I.D. (Air Delivered Seismic Intrusion Detector) Devices at U.S. Air Force Museum, 1:55 -


Locating this ADSID on this web page because it also contains the TXnnn llike modules.
In Fig 2 below the top cylinder is the battery also shown in Fig 4 as the left cylinder.
In Fig 4 is shown the top of the TC470A with knobs marked:
S3: OFF, 7, 14, 28, 45, OFF (maybe 7 days (1 week), 14 days (2 weeks), 28 days (4 weeks), 45 ( 1-1/2 months)?
S4: 1, 2, 3, 4, 5, 6 ?

There are three cylinders: Battery, TC470A  Signal Processor & "4" Transmitter/Receiver "Destruct Removed".  The transmitter programming plug is between the TC470A and destruct.

Under the end plate of the Signal Processor/Controller (Fig 6 below) there are two matching circuits going to the antenna connector, so maybe a diplexer allowing for both transmission and reception.

Fig 1
ASID with TCnnn
                  modules, no internal battery. Functin?
Fig 2 BNCm-Antenna
& Instructions
ASID with TCnnn
                  modules, no internal battery. Functin?
Fig 3
ASID with TCnnn
                  modules, no internal battery. Functin?
Fig 4
ASID with TCnnn
                  modules, no internal battery. Functin?
Fig 5
ASID with TCnnn
                  modules, no internal battery. Functin?
Fig 6 Signal Processor "4" shown
with cable to BNC antenna jack.
ASID with TCnnn
                  modules, no internal battery. Functin?

Alarm Set, Anti-Intrusion, Restricted Area, AN/GSQ-159 (V) (DSID)

I'm placing this here because the batteries for this unit and the ADSID HIT Assembly above both use a battery in a custom aluminum housing that has a minature "D" connector.

I think DSID stands for Disposable Seismic Intrusion Detector.  This is consistent with a custom battery that no one could replace.


Fig 1
Alarm Set, Anti-Intrusion, Restricted Area,
                  AN/GSQ-159 (V) (DSID)
Fig 2
Alarm Set, Anti-Intrusion, Restricted Area,
                  AN/GSQ-159 (V) (DSID)


Name: Alarm Set, Anti-Intrusion, Restricted Area, AN/GSQ-159 (V) (DSID)
Contract: DAAk02-70-C-0566
FSN: 6330-402-2026
Part No. 717500-106
Serial No. OCE
ID Code:
Confidential When All Items are Filled in Below:
Date Installed:

Confidential When Filled In
Wehn filled in with date installed and location data, this tag contains information affecting the national defense of the United States within the meaning of the Espionage laws, Title 18, U.S.C., Section 783 and 784.  The Transmission of the Revelation of it's contents in any manner to an unauthorized person is prohibited by law.

Excluded from automatic regrading DOD Dir. 5200.10 does not apply.

AN/GSQ-159(V) (DSID) Installation Instructions
1. Remove Identification Tag & Record Sensor Location
2.Implant Sensor and Erect Antenna
3. Turn Power Switch to Test
4. Check Operation with AN/USQ-46 or RF Indicator
5. Turn Power Switch To Arm
6. Complete Camouflage of the Sensor and General Area


This was part of the package deal along with the GSQ-171, so I'm putting it here even though it does not use the TCnnn modules.
No identifying markings.  The battery compartment seems to have a built-in "7.5" seismic sensor.

Fig 1
Fig 2 PL-259 Antenna connector.
Fig 3
Fig 4 Battery: Mallory 303819 (DC: 0269)
"7.5" Seismic Sensor

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 that 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 completely 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 11-5821-356-23 RADIO 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
3210990 Dropped inflatable penetrometer, John L Cantrell, TI, 1965-10-12, - balloon inflates if ground is above specified hardness (OK for tanks?)
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.
6531965 Modular open system architecture for unattended ground sensors, Stephen G. Kaiser, Mark D. Hischke, Shannon Mary Nelson, Stuart J. Collar, Dana Lynn Bourbonnais, Northrop Grumman Systems Corp, 2003-03-11, -
Cites 28 patents:

3704764 Air deliverable seismic system, Harold B Henderson, TI, 1972-12-05, -

4492111 Rheological penetrometer, James L. Kirkland, 1985-01-08, - ground conditions such as soil or water and other vari ous fluids or liquids which may be examined or tested by the apparatus.

4630246 Seismic-acoustic low-flying aircraft detector, Robert J. Fogler, AF, 1986-12-16, - correlates seismic & acoustic to detect "under the radar" aircraft

4683474 Survivable ground base sensor, George W. Randig, AF, 1987-07-28, - radar system with each sub-array >=10 miles from each other to survive nukes, centered on North Dokota

4722282 Payload-carrying projectile, Reinhard Synofzik, Rolf Hellwig, Rheinmetall AG, 1988-02-02, - air dropped sensor

4818994 Transmitter with internal serial bus, Kelly M. Orth, Steven M. Quist, Roger L. Frick, Randy K. Paschke, Rosemount, 1989-04-04, - n industrial process control

5075857 Unmanned compliance monitoring device, Joseph S. Maresca, 1991-12-24, - "Unmanned compliance monitoring device, data communication network and transaction processing apparatus for monitoring earth tremors, collecting and reporting seismic data profiles and calculating an earthquake epicenter incorporating"

5339281 Compact deployable acoustic sensor, Patrenahalli M. Narendra, Russell D. Braunling, II William J. Wegerer, Jonathan C. Werder, Northrop Grumman Innovation Systems (Alliant Techsystems Inc), 1994-08-16, - acoustic target detection and classification

5432546 Weapon impact assessment system, Lee B. Cargill, Enel Co, 1995-07-11, - camera released from weapon trails it on tow line.

5554994 Self-surveying relative GPS (global positioning system) weapon guidance system, Arthur J. Schneider, Raytheon (Hughes), 1996-09-10, - looks like differential RTK GPS (Wiki)

5575438 Unmanned VTOL ground surveillance vehicle, Kevin P. McGonigle, John Ferraro, James P. Cycon, Raytheon Technologies (United Technologies), 1996-11-19, - flying saucer, counter rotating props inside donut, surveillance pod above.

5621669 Moisture sensor probe and control mechanism, Eyjolf S. Bjornsson, 1997-04-15, - modular moisture probes for large lawn sprinkler system

5662165 Production wells having permanent downhole formation evaluation sensors, Paulo Tubel, II Albert A. Mullins, Kevin Jones, Frank D. Richardson, Baker Hughes Holdings, 1997-09-02 - modular system for multiple oil wells

5730219 (similar to the above)

5812068 (similar to the above)

5841280 Apparatus and method for combined acoustic and seismoelectric logging measurements, Western Atlas Int, 1998-11-24, - modular oil well probe

5867257 Battlefield personnel threat detection system and operating method therefor, Robert R. Rice, Mark S. Zediker, McDonnell Douglas, 1999-02-02, - micro-Doppler LADAR, REmotely Monitored Sensors (REMS), unlike geophones & Goubau Lines (Wiki, 2685068, 2921277) which put soldiers at risk to install, this system looks toward the enemy but does not need to be installed in hostile areas.

5884867 Stabilizing apparatus, Tal Gordon, Dan Omry, Guidex Ltd, 1999-03-23, - a gimbal below a parachute stabilizes a hi res camera

5904210 Apparatus and method for detecting a location and an orientation of an underground boring tool, Gregory S Stump, Christopher T. Allen, Vermeer Mfg,  1999-05-18, - used to control a boring bit to tunnel under roadways &Etc.

6006338 Process transmitter communication circuit, Randy J. Longsdorf, Grant B. Edwards, Richard L. Nelson, David L. Pederson, Rosemount, 1999-12-21, - modular process monitoring

6056237 Sonotube compatible unmanned aerial vehicle and system, Richard L. K. Woodland, 2000-05-02, - UAV is generally comprised of modular Sections

6072524 Electronic observation post with communications relay, John E. Davis, Veron R. Creekmore, Boeing, 2000-06-06, - A SIRPS (Staring Infrared Panoramic Sensor) mounted on a Rogollo wing (Wiki) (B.C. or maybe a Kytoon (Wiki)

6127926 Intrusion sensing systems, David John Dando, 2000-10-03, - special radar to detect climbing on building scaffolds

6130642 Method and system to improve GPS navigation, Robert C. Woodall, Jr.Felipe A. Garcia, Navy, 2000-10-10, - "...provide a clandestine method and System that improves the navigation accuracy of GPS-guided vehicles while remaining dif ficult to detect or undetectable by enemy Surveillance."  The pseudo-lite position is accurate to a few centimeters after sitting for an hour.  An incoming munition activates the pseudo-lite which transmits a GPS signal which provides a much more accurate position that it can get from a satellite.

6164179 Submarine deployable vertical launch spar buoy, Martin Buffman, Navy, 2000-12-26, -

6260797 Transformable gun launched aero vehicle, Miles R. Palmer, SAIC, 2001-07-17, - modular air vehicle

6400647 Remote detection system, Gary B. Huntress, Navy, 2002-06-06, - can identify aircraft takeoff & landing (maybe aircraft type?)
5721712 Aircraft detection system, Kenneth M. LaPointe, Navy, 1998-02-24
4322828 Seismic aircraft maneuver classifier, Dave Hoff, Peter H. Vansloun, Northrop Grumman, 1982-03-30
4408533 Acoustic amplitude-threshold target ranging system, Owen, Suhler & Peters, AF, 1983-10-11 - for firing munitions at closest approach
5060206 Marine acoustic aerobuoy and method of operation, DeMetz, Honeywell, 1991-10-22 - Uses Helmholtz resonator as part of microphone - describes prior art patents. HRfreq(Hz) = (RPM *No. of prop blades)/60
4533945 Process and arrangement for aerial observation and/or communication for a submerged submarine
3258595 Remotely operated self-powered observation device including remotely controllable visual scanning means
3651286 Lavalier microphone assembly protected against friction noises
4189786 Radio buoy assembly
4203109 Submarine communication system
3999183 Floatable radio antenna

5978313 Time synchronization for seismic exploration system, Harold L. Longaker, Trimble, 1999-11-02
Cited by 38 patents
6816109 Method for automatic association of moving target indications from entities traveling along known route, Steven A. Schwartz, Northrop Grumman, 2004-11-09, - can be generalized to finding convoys, Hough transform (Wiki, 3069654), How invented,

6898378 Shock-resistant backplane utilizing infrared communication scheme with electrical interface for embedded systems, Shannon M. Nelson, Stuart J. Collar, Mark D. Hischke, Northrop Grumman, 2005-05-24 - maybe a way to eliminate the ring connector?
7079778 Rugged shock-resistant backplane for embedded systems, Shannon Mary Nelson, Richard Joseph Paul, Mark D. Hischke, Northrop Grumman, 2006-07-18

20060213290 Unattended ground sensor assembly, Jerome Kolarczyk, Joseph Wisneiwski, Northrop Grumman Systems Corp, 2007-03-20, - looks like TCnnn modules?

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

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