PRC-112 Survival Radio

Brooke Clarke 2010 - 2020

AN/AYD-1 Personnel Locator System (PLS)
    Combat Survivor Evader Locator (CSEL) PRQ-7
KY-913 Program Loader
Battery Adapter
PRC-112 Survival Radio &
              Programmer Kit
Fig 1 Suitcase with PRC-112C & KY-913

              Survival Radio
Fig 2 PRC-112C Survival Radio

PRC-112C Battery Connector
Fig 3 PRC-112C Battery/interface Connector

KY-913 Radio Connector
Fig 4 KY-913 Radio Interface Connector
              Survival Radio Programmer
Fig 5 KY-913 Programmer

KY-913 Battery Connector
Fig 6 KY-913 Battery/Test Connector
BA-5112/U PRC-112 Battery
Fig 7 BA-5112/U


The PRC-112() Survival Radio replaces the PRC-90 family of survival radios that are issued to military aircraft crew members.  The problem with the old survival radios was that they were simple beacon transmitters with no ID capability so when one went off accidentally (a common occurrence considering that there are roughly 556,000 121.5 MHz beacons and 429,000 406 MHz beacons) there was not an easy way to tell if the signal was real or not making for a lot of wasted effort.  Satellite monitoring of the old analog survival beacons was shut down on 1 Feb 2009. 

The new 406 MHz survival beacons each have a serial number and other identification information built in.  A rough position can be determined just from the 406 Mhz carrier and the motion of the satellite that's receiving it.  A much better position can be obtained if the beacon transmitter includes a GPS receiver.  As of 2009 there were about three quarters of a million 406 MHz beacons operational.

In the movie "Behind Enemy Lines" this is the radio used by Owen Wilson throughout most of the story.  It even makes static noises after the tank attacks a building in Hoc with the battery removed.

AN/AYD-1 Personnel Locator System (PLS)

The AYD-1 is the complete system consisting of:

PRC-112 Aircrew Member Survival Radio

This radio was developed during the late 1980s and throughout the 1990s and was finalized in the middle of the decade starting in year 2000.  It's intended for use by all military air crews.  (Wiki: Survival Radio, Emergency Position Indicating Radio Beacon EPIRB)

The original PRC-112 (no letter) looks identical to the PRC-112C except for the label.

This radio had some teething problems.  It may also be the radio related to this story:
ProPublica: Faulty Equipment, Lapsed Training, Repeated Warnings: How a Preventable Disaster Killed Six Marines - Video: Adrift- How the Marine Corps Failed Squadron 242 12:11



PRC-112 Aircrew Member Survival
243 Beacon
243 coms
Custom freq B
Custom freq A
282.8 coms
121.5 coms
121.5 Beacon
The PRC-112 is a step up from the PRC-90 in that it has more channels (two of them can be programmed) and Distance Measuring Equipment (wiki: DME) built in.  When a search aircraft gets within line of sight of the PRC-112 it can send a burst transmission on any of the non beacon channels and if the PRC-112 is not transmitting it will respond to the aircraft.  Note the aircraft needs to know the ID# (000000 to 999999) of the radio.  While doing so a light on the PRC-112 will be on for about eight seconds telling the survivor that someone is getting his range and bearing.

This version does not have GPS and does not support SARSAT 406 MHz digital data.
The TS-4317 Communications analyzer supports the DME mode of the PRC-112.
Aproximatley 25,000 made.
There are 9 variations on the basic PRC-112.
Fig 8 PRC-112 Open
Fig 9 PRC-112 Inside Modules

In Fig 9 above showing the modules inside the PRC-112 you can see a distorted module to the left of the TADIRAN Transponder.  The module at the right top (next to the Transponder) is a 72 MHz TCXO.  The module at the front marked D793 has a coax that leads to the antenna.  The right hand red wire at the very upper right (in the narrow part of the chassis) is connected to the battery socket negative battery terminal.  There's 10 Ohms resistance between the two red wires when the power is on or off..  The metal can with the two red wires may be a filter in the negative DC power line.

Opening (probably the same for all versions)

The cover is held on by what may be Bristol Key Chart head metric 2.2-0.45x9 mm screws. A 0.050" hex wrench will fit into the hole, but when turned tends to strip leaving a round hole.  Kroil penetrating oil is also a helpful thing to have on hand.  Some of the screws may have been epoxied to prevent their removal (maybe also the reason for using Bristol heads).  More when the wrenches arrive.

The L-key wrenches arrived are are the wrong set.  This set marked "Bristol Wrench" & "Spline Key Kit" contains 10 keys and is sold on eBay as "SS-408 - Bristol Spline Wrenches Collins & Bell Howell".  It contains: -060, -069, -072, -076, -096, -111, -133, -145, -168, & -183 spline L-keys.  All of them too large.
Bristol Wrench
          Kits: SS-408 & SS-508

The "SS-508 Spline Key Kit"  is the one needed for the PRC-112 cover screws and has 9 L-keys. 
Max-Gain Systems sells them on line for ham radio and electronics.

After picking out the epoxy on a few screws and using Kroil for many days there were screws that just would not budge with reasonable force.  Using a 500 Watt soldering iron on the screw head did not help.  What worked was drilling out the screws.

Once the cover is removed to free up the module assembly the four corner screws on the printed circuit board can be removed.   Leave the four screws in the center of the PCB since these hold modules.  The top (closest to the cover) internal PTT screw needs to be removed since it also goes into the module assembly.


Adds type 1 Voice encryption. (Wiki)

PRC-112B GPS-112 Hook-112

This is the basic PRC-112 with the Motorola GPS applique and Hook waveform.
Works with the Quickdraw 2  interrogator, Rockwell RSC-125G, Cubic ARS-6 Ver12.
The PRC-112B (and later versions) probably looks like the PRC-112G, i.e. with the LCD screen and input buttons for 2-way text messaging.


adds GPS, 2-way messaging and encryption to the PRC-112C in a new applique.
Works with the Quickdraw 2  interrogator, Rockwell RSC-125G, Cubic ARS-6 Ver12.


Made by Motorola this is just the basic PRC-112 radio without GPS and without SARSAT data.  It has the improved sensitivityhe and knob upgrades (GD p/n 01-P21261J004).
The June 27, 2003 GD contract adds GPS, 2-way messaging and encryption to the PRC-112C to make a PRC-112B1


In Fig 3 above of the battery connector you can see that there are five electrical contacts surrounding the two battery terminals.  Two of these are for the programmer interface.  In Fig 4 above of the top of the KY-913 programmer you can see the two programming pins surrounding the two battery terminals. Note in Fig 6 above  that the KY-913 battery connector has the same five terminal arrangement surrounding it's battery terminals.  This must for testing and flashing the memory of the programmer.  There is an adapte cable made by Aeroflex that interfaces their communications tester to the radio battery connector and has the 5 interface pins in addition to the two battery terminals.

There might be an antenna adapter that can be installed by removing the tape antenna and screwing it onto the radio so that a D&M type satcom antenna can be fitted.

The antenna is held to the radio with what looks like a 5/16-24 bolt.
There appears to be a coax connection possible but it would require a special adapter with 5/16-24 threads and a center conductor.
PRC-112C Opened


Made by Engineering and Professional Services (EPS).  Finished their 1,000th PRC-112D on March 24, 2006.  Made by upgrading the modules in the PRC-112.  Adds Built In TEst (BITE) and battery life indicators.  EPS worked with Tadiran Spectralink on the PRC-112D. They also developed a Helium leak test for the PRC-112C because some radios got seawater inside.


Feb 01, 2003 Made by Tadiran Spectralink Ltd.  See the PRC-112D above.


Might not have been made?

PRC-112G  Hook2 CSAR


Made by General Dynamics and includes GPS, UHF satcom digital 2-way messenging & encryption.  Uses Software Defined Radio (SDR) technology.
Works with the Quickdraw 2  interrogator, Rockwell RSC-125G, Cubic ARS-6 Ver12.
Optional SARSAT digital mode on 406.028 MHz
Has LCD screen and a number of buttons to interface with the screen.

June 16, 1993 Motorola, Inc., GEG, Scotsdale, Ariz., $8.3 million new work modification to a firm fixed-price contract for the production of a basic quantity of 611 AN/PRC-112 Survival Radio Sets, an option quantity of 1,1583 AN/PRC-112 Survival Radio Sets and an associated data item. These radio sets are necessary to achieve first-pass rescue capability for downed crewman, minimizing the loss of survivors to the elements or the enemy.

Maybe the kit shown at the top of this page.
APRIL 20, 2000 AN/PRC-112C SURVIVAL RADIO SETS SOL DAAB07-00-R-B035 DUE 051200 POC Cindy Cook, Contract Specialist (732)532-5415, Vernay Salas, Contracting Officer (732)532-1257 WEB: CECOM Acquisition Center's Business Opportunties page, E-MAIL:, This acquisition is being issued as A Sole Source to Motorola, Scottsdale, AZ. This is to acquire 635 each AN/PRC-112C Survival Radio Sets.
Sep 28, 2001 Motorola sells it's Integrated Information Systems division to GD.
June 27, 2003 General Dynamics Decision Systems, Inc., Scottsdale, Ariz., is being awarded a $6,354,315 firm-fixed-price contract to provide for assembly applique added to the AN/PRC-112 or AN/PRC-112C radio to make an AN/PRC-112B1 (Global Positioning System (GPS) capability) radio. This applique adds GPS, 2-way messaging and encryption to an AN/PRC-112 Multi-Mission Transceiver. Price includes installation on 1,167 customer-furnished AN/PRC-112s at $5,445 per kit. Total funds have been obligated. This work will be complete September 2003. The 16th Special Operations Wing, Hurlburt Field, Fla., is the contracting activity (08620-03-F-0154).
Dec. 5, 2000

Motorola (NYSE:MOT) Tuesday introduced its Combat Search and Rescue (CSAR), GPS-112 Personnel Location System.

This technology will combine beacon, radio, transponder, GPS and two-way messaging capabilities into a hand-held radio and interrogator system

Motorola's GPS-112 transceiver sends encrypted global positioning data and two-way messages to provide essential, quick and accurate location and rescue information to aid in finding the grounded soldiers' location.

Motorola's Quickdraw Interrogator can quickly plug into the intercom system of virtually any aircraft, transforming it into a CSAR platform. The information is communicated in a single, short burst to the GPS-112 hand-held radio.

This technology provides rescue crews with a very accurate, Low Probability of Interception/Low Probability of Detection (LPI/LPD) system enabling them to locate missing crewmember(s).

"The GPS-112 Personnel Location System combines the field-proven benefits of the Motorola CSAR radio with the convenient hand-held Quickdraw Interrogator to provide our customers with a high level of accuracy," said Gary Johnson director of radio products business unit of the Motorola Information Security Systems and Products Division.

"Military and government personnel, around the world will have a new, powerful, secure option with Motorola's Personnel Location System."

Hook 112 adds civilian GPS to the basic PRC-112 as an applique done by Motorola. 

Combat Survivor Evader Locator (CSEL) PRQ-7

The CSEL has replaced the PRC-112.

The Combat Survivor Evader Locator (CSEL) (FAS: CSEL, Boeing, Thales, )  integrates the GPS into the radio and supports the digital SARSAT data.
Boeing CSEL
Photo from Boeing
The FY '98 DoD Director of Operational Test and Evaluation (DOT&E) report says that Boeing's [BA] Combat Survivor Evader Locator (CSEL) system, which guides rescue units to downed pilots, is not acceptable for combat use. "The CSEL configuration tested is not effective and not suitable," the report says. CSEL is intended to replace the PRC-90 and PRC-112 survival radios now used by aviators of all four services, providing a satellite communication link and real-time position data.

FT. BELVOIR, Va.-The Air Force and Boeing [BA] recently said that the Combat Survivor Evader Locator (CSEL) program has demonstrated significant improvements in the past year after the Pentagon ruled it was not acceptable for combat use.

The CSEL's performance showed significant improvement when compared to the testing results from the engineering and manufacturing development phase, Air Force Lt. Col. Norman Albert, CSEL program manager, told sister publication Defense Daily at a briefing

CSEL Accessories

J-6431/PRQ-7 Adapter, Radio Set (NSN: 5820-01-500-0556) - Cloning kit

CSEL Planning Computer Software

BB-2001A/U AN/PRQ-7 Rechargeable Battery Pack (NSN: 6140-01-534-3856)

BA-5301/U AN/PRQ-7 Non-rechargeable Battery Pack (NSN: 6135-01-512-8740)  The non-rechargeable battery pack provides 2.8 Amp-hours of power and weighs only 8.4 ounces. The pack contains a memory device that communicates its remaining capacity to the CSEL HHR. DOT approved for commercial ground/air transportation.

J-6769/U AN/PRQ-7 SPC Adapter, PN: BTA-70581-2, (NSN: 5980-01-526-8017) Used with the PP-8498 SPC to charge two CSEL Rechargeable battery packs. Backward compatible to the earliest CSEL battery packs. Four (4) are required to populate all stations in PP-8498 SPC.

Radio Set Adapter (RSA Nano), PN: 4866118-101 Installs between the battery and HHR for mission parameter upload and download. Used to load SAASM GPS Crypto Keys. Includes Serial/Crypto Fill Y-Cable, quick-guide and canvas pouch.

CSEL HHR XX90 Adapter, PN: 4866118-102, Ba-5590 family to PRC-112 battery adapter

Replacement Parts

CSEL HHR Blade Antenna (Replacement Kit) 4866112-103-001 5985-01-502-7930
Earphone CEP601-CO3S 5995-01-502-9465
Earphone Ear Tips (Assorted Sizes) CEP300-EMXT 5965-01-504-1051
Strap/Pouch 4866110-421-001, 721-00451 5935-01-458-9450

KY-913 Program Loader


These are the devices that find the survival radio.  Most are mounted in aircraft either as avionics or as an add on to the intercommunication system.  There are also suitcase interrogators and hand held units.  The hand held unit plugs into the aircraft intercommunications system (i.e. Quickdraw).  The suitcase unit may contain a LST-5 UHF Satcom radio and so could be operated anywhere.

The GD Satcom base station uses the PRC-112G (or maybe a special version with external antenna connector and laptop interface to send and receive encrypted digital messages.


NSN 6135-01-235-4168
Chemistry (Primary)
Output: 11.8 Volts
2000 mAh
Length: 3.06 inches
Width: 2.25 inches
Thickness: 1.54 inches

Battery Adapter

Takes 8each Energizer LS91 AA cells, i.e. a "12 Volt" adapter marked for use only on the PRC-112D.

Fig 1
                  Battery Adapter
Adapter, Battery

NSN: 9540-01-504-8134
Fig 2
                  Battery Adapter
Use only 8 each Energizer 1.5 Volt LIthium 6135-01-333-6101.

Do not charge, short circuit, incarcerate or mutilate this battery otherwise battery may vent or rupture releasing toxic materials.

Warning: Do not use rechargeable batteries.
Fig 3
                  Battery Adapter
Battery Adapter


Use only on AN/PRC-112D Survival Radio

Warning: Do not use rechargeable battteries in this adapter.
Fig 4
                  Battery Adapter
To Open:
1. Remove locking "U" shape clip.
2. Squeeze notched fingers together and push them down to release end plate.

The convention that battery negative is the spring and the fixed contact is positive is NOT true for this adapter.
You MUST follow the polarity guide!  This may become a problem if the stick on guide is not noticed.
Black printing against Olive drab is very hard to see let alone read.
Fig 5
                  Battery Adapter

The battery adapter is thicker, it protrudes at the front and back of the radio. 
It's also wider and protrudes to the right. But not at all problematic.




5820-01-417-8752 Mot
applique adds GPS

App. adds GPS, 2-way messaging and encryption

AN/PRC-112D 2006
5820-01-500-1535 EPS
GPS + AA batteeries


121.5, 123.1 MHz; 225320 MHz; 406 SARSAT 406.028 MHz




3656159 Minimum size Transponder, (Motorola), Apr 1972, 342/51 ; 327/176; 327/294 -
5394156 Digital range turn-around for tracking, telemetry and control transponder, (Motorola), Feb 28, 1995 -
5726663 Survival radio interrogator, (Motorola), Mar 10, 1998, 342/419 ; 342/357.09; 342/386; 701/213
Survival radio interrogator (1) transmits upon request a message including an identification of survival radio (3). Upon receiving and processing this message, survival radio (3) determines its position from the Global Positioning System and transmits a message back to the search aircraft...
This is the GPS-112 and Quickdraw Interrogator.
5365451 Mobile unit tracking system Motorola
Nov 15, 1994 GPS based
5389934 Portable locating system Business Edge Group Feb 14, 1995
5414432 Position locating transceiver Motorola
May 9, 1995 GPS, Iridium,
5438321 Location system (underground miners)

Aug 1, 1995
5515419 Tracking system and method for tracking a movable object carrying a cellular phone unit, and integrated personal protection system incorporating the tracking system Trackmobile May 7, 1996
5517199 Emergency locator device Aerodata May 14, 1996

6011510 GPS based search and rescue transceiver, (Motorola), Jan 4, 2000, "Hook PRC-112" to add GPS to the PRC-112
5334974 Personal security system
Aug 2, 1994 Cell phone
5392052 Position reporting emergency location system
Feb 21, 1995
5414432 Position locating transceiver Motorola May 9, 1995 GPS, Iridium,
5418537 Location of missing vehicles Trimble May 23, 1995
5420883 Train location and control using spread spectrum radio communications Hughes May 30, 1995
5497149 Global security system (object track confirmation)

Mar 5, 1996
5502446 GPS-based automatic target reporting and finding network and components (Rescue radio transmits on GPS L2 freq)
Trimble Mar 26, 1996
5517199 Emergency locator device Aerodata May 14, 1996 GPS
5519403 Global positioning system communications multi-interface Motorola May 21, 1996 OMEGA
5526357 Communication system and method for determining the location of a transponder unit
Jun 11, 1996
5563607 Time and/or location tagging of an event
Oct 8, 1996
5748147 Position locating rescue transceiver
May 5, 1998
5847679 GPS based search and rescue system
Dec 8, 1998

7355513 Ultra-reliable personnel position locating system, Kenneth H. Brockel, et al (Army), Apr 8, 2008,
Class:  340/539.13 ; 340/539.11; 342/357.06; 342/357.07; 455/404.2; 455/456.1; 455/90.1; 701/213; 701/214
Is an improved method of using the AN/AYD-1 Personnel Locator System by adding GPS to the search aircraft and using Time Of Arrival and cooperating beacons between search aircraft to improve the survivor location from about 100 meters to better than 10 meters.
This is the GPS-112 and Quickdraw Interrogator.
5726663 Survival radio interrogator, (Motorola), Mar 10, 1998
References prior are PRC-112
"The search and rescue interrogators are typically suitcase sized and include a GPS receiver, portable computer, LST-5 (UHF) radio, battery, power supply, etc. and weigh approximately 60 pounds.  This suitcase interrogator is also very expensive."
5847679 GPS based search and rescue system, (Motorola), Dec 8, 1998 -
6020845 Satellite for increasing the utility of satellite communication systems, (Stanford Telecommunications), Feb 1, 2000 - works with TDRSS satellites
6552652 Rescue device, (Synergy Microsystems), Apr 22, 2003 - air dropable vibration sensor equiped beacon w/GPS
6785553 Position location of multiple transponding platforms and users using two-way ranging as a calibration reference for GPS, (DirecTV), Aug 31, 2004 - transponder
7003278 Portable search and rescue system, (Tadiran), Feb 21, 2006


Survival Equipment
PRC-90 Survival Radio
URC-68 Survival Radio
ACR/RT-10 Survival Radio
SDU-5/E Distress Strobe Marker Light
SDU-30 Distress Marker Light
Survival Radios

Bristol wrench patent

1075710  - source: Max-Gain Systems
Bristol wrench
        Patent 1075710


Mike Murphy - often has the PRC-112() and/or Programmer
Cospas-Sarsat -
AFCEA - SIGNAL - Taking the Search Out of Search and Rescue, By Henry S. Kenyon, May 2001 -
CBD - JANUARY 3,2000 PSA#2507 - 37 ea. Program Loaders, P/N 01-P21700J001, KY-913/PRC-112, NSN 7025-01-279-5308
Aeroflex - RCTS-003B Radio Communications Test System works with PRC-112, A, B, B1, C, D and G versions
GD - HOOK2 GPS Combat Search and Rescue (CSAR) System -

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