Modular Outdoor Intrusion Detectors

Brooke Clarke 2009 - 2018

Unattended Ground Sensor Set (UGSS), AN/GSQ/257
Day/Night Imager Version II, AN/PSQ-21
Hand-Held Programmer-Monitor (HHPM), AN/PSQ-22
Radio Repeater Set, AN/GRQ-32
Modulated Beam Detector / EMitteR
Modulated Beam Detector /S?? H?? D??
Modular Break Wire Sensor
3-socket Connector


These were obtained from American-MilSpec but there's not much info available on them.

If you know anything about these please let me know.

These may be part of one of the following systems:
REMBASS - Remotely Monitored Battlefield Sensor System - uses Passive IR, Magnetic, Seismic, CCD Camera (not IR beam & not wire break)
Friendly Fire (Wiki): "There is also some development of remote sensors to detect enemy vehicles the Remotely Monitored Battlefield Sensor System (REMBASS) uses a combination of acoustic, seismic vibration, and infrared to not just detect, but identify vehicles."  I wonder if this capability really worked?
I-REMBASS - Improved - Remotely Monitored Battlefield Sensor System
CLASSIC - Covert Local Area sensor System for Intrusion Classification

Maybe Tactical Remote Sensor System (TRSS) -
Tactical Remote Sensor Systems System-of-Systems (TRSS-SoS)
Description at Global Security web page makes two pop-ups that lock up Firefox Do Not use them

Related to Geophysical MASINT (Wiki)
L-3 Communications Corp supplies this system on a Firm-Fixed Price (FFP) contract.

Components of REMBASS (links to Wiki): infrared MASINT, Magnetic MASINT, seismic MASINT, and acoustic MASINT (MASINT)


Tactical Remote Sensor Systems (TRSS) System-of-Systems (SoS) has the following components:

Unattended Ground Sensor Set (UGSS), AN/GSQ/257

A suite of hand emplaced sensors that operate unattended and detects activity through seismic, acoustic, infrared, and magnetic sensing technologies. The UGSS primary sensor is the Encoder-Transmitter Unit Version II (ETU-II).

Day/Night Imager Version II, AN/PSQ-21

An integrated system of cameras, radios, and image processing hardware that captures and transmits images from areas under surveillance to distant sensor monitoring systems. Upon detection of sufficient pixel changes in the Field of View (FOV), the Imager captures an image. The Imager then uses its radio systems to send the image to sensor monitoring sites either directly, satellite communications, or via one or more Radio Repeaters. The Imager is remotely configurable to change operational modes, select camera controls, and change radio frequencies.

Hand-Held Programmer-Monitor (HHPM), AN/PSQ-22

A portable, programmable, dual-band, sensor emplacement tool for programming sensor equipment, monitoring sensor activity, recording sensor positions, and testing Radio Frequency (RF) communications paths between remote device sites. Sensor imagery is displayed in the HHPMs Tactical External Viewing Assembly (TEVA). The TEVA may also be connected directly to the TRSS Imager when the user desires to see a cameras field of view. The HHPM menu provides a variety of user-selectable display preferences and test messages designed to enable Marines to perform sensor tests and direct (cabled) reconfiguration at sensor emplacement sites. An earphone assembly and night vision filters are provided to enable operation when light and sound discipline is required.

Radio Repeater Set, AN/GRQ-32

RT-1847/GRQ-232 Radio
          Repeater Set, Tactical Remote Sensor Systems (TRSS)
          System-of-Systems (SoS)
A dual-band sensor retransmission system that enables communication between deployed sensors and monitoring sites when direct sensor-to-monitor radio line-of-site is precluded by terrain. The Radio Repeater is remotely configurable to use various modes, filter messages, mask out problematic sensors, and change operating frequencies.


Each of the units I have is of a size that fits in your hand.  It's still not clear which system these belong to.  If you know, let me know.


                Outdoor Intrusion IR Light Source

Modulated Beam Detector / EMitteR

Above is guess about the meaning of letters on unit.

This unit has a battery compartment that holds three 9 V batteries wired in parallel.
When 9 volts is applied from a bench supply the current draw is near zero.  BUT,
looking into the optical element with the PAS-6 shows modulated IR light.  I could also see the light in the viewfinder of the camera, and tried three times to capture it, but that didn't happen.  With the very low current draw and using three batteries this unit may run in the field for a number of months if not years.


                Outdoor Intrusion IR Light Detector

Modulated Beam Detector /S?? H?? D??

This unit has the same first three letters and the above unit and looks to be the matching detector.

Connector is marked:
The cable is potted onto the connector.


MBW Outdoor
                Intrusion Detector

Modular Break Wire Sensor

When the cap is removed three fine wires can be seen. 
(1) One of them comes from the central hole and can be pulled out, like there's some length spooled inside.
(2) A wire loop starts on one side and terminates on the other side.
(3) a short fixed length wire about 1/2" long.

Push Button.


Notch that will hold the connector.

Same connector as above.

MBW Back Side diagram

MBW Modular
                Intrustion Alarm Wire Break diagram
There's a diagram on the back of the MBW unit that seems to depict someone breaking a wire tied between two trees.  To the right of the diagram is a vertical line and the letter "B".

Why the three wires?]
How does it detect a wire break or does it?

The notches and circular hole may be related to mounting options.

3 Socket Connector


The mating connector is the PT02A-8-3S. 
aka MS3110F-8-3S
Available from William Perry.



Outdoor Intrusion Detectors and Related Equipment -
TRC-3, PEWS, USQ-42, Turd - geophone based
GSQ-154 - Alarm Set, Anti-Intrusion, Restricted Area - geophone based
GSQ-160, USQ-46, TS-2963, PP-6446  -  TCw - cylindrical module pinouts. GSQ-160 uses 60 & 57.5 MHz to sense field changes
GSS-26 - minimal info
Intrusion Alarm Patents -
USQ-42,  Igloo White, USQ-46 - details
PSR-1 - geophone based intrusion detector



Ground Sensor Platoon - The Marine Corps' unknown collection asset

Brooke's Home Page  Brooke's Military Information page -

[an error occurred while processing this directive] page created May 19 2009.