Hughes won a competition to develop an HF radio to replace the PRC-47. The Collins PRC-515 was considerably larger and heavier.
Frequency coverage is 2.0000 to 29.9999 MHz USB, LSB, CW (up to 300 WPM, i.e. GRA-71 compatable), FSK/DPSK up to 2400 bps. It's also known as the Improved High Frequency Radio, IHFR. Later PRC-104 models included compatibility with the Hughes C-11525/G anti-jam controller (STAJ) which is a frequencyhopping system.
The PRC-104 is a modular radio that can be configured in a number of different ways:
Test DC Power Cable
Battery Extender Cable
Battery Charging Cable
Zinc Battery Case
BA-5590 Battery Case
||Dual BA-5590 Battery Case|
5590BA batt adapt
5590BAv2 batt adapt
Tie Down Strap
Key (Modified KY-116/U)
||Amplifier Ant Coupler|
meter Fishing Pole Ant
||16' or 32' whip
Top color dots on PCB match connector color
Top PCB folded open
Bottom - has two PCBs
Bottom two PCBs folded open
PRC-104A Front Panel
Control Connector 19 Sockets
PRC-104A Front Panel Back Side
Radio D-sub connector looks same as on PRC-104
PRC-104A (RT-1209A) Front Panel Versions
| Variations in
Round buttons w/boot
Round buttons w/o boot
Looks like new never used
No boss under button panel
Round buttons w/boot
If you look at the AUDIO connector it's angled.
The board behind the connector has broken solder
joints on it's support pins.
with pin 1 where the "1" is
87990-75502C 7059-1 A 53669 9109
Using a BK Precision 1786 lab power supply, on receive the PRC-104 draws 0.16 Amps and on transmit the current varies a lot with voice peaks, maybe 1.6 Amps average, but the peaks might go up to 3 Amps or more. In CW mode with the key down the current goes slightly over 3 Amps, but this power supply is only rated for 3 Amps. It seems that a large capacitor on the input would be good to handle the peaks.
The center pin is Positive. The Negative pin is closer to the ANT SEL switch than the No Connection pin.
Note these pins are on the AM-6874 not the RT-1209.
This case has a built-in battery charger. It's input is probably a military vehicle "24 Volt" system.
Why Two BatteriesThe 7875 holds two each BA-5590 batteries, with each BA5590 connected in parallel to provide 30 Volts to the radio. The front of TM 11-5820-919-12 has a couple of warning pages about the BA-5590 and a statement that it contains a 3.2 Amp slow blow fuse. It's my understanding that today the BA-5590 has a 2.25 Amp slow blow fuse. In the specifications table in TM 11-5820-919-12 the Tx current is given as 3.5 Amps at 24.0 Volts. The 24.0 Volts comes from the battery label showing two 12 Volt sections for a nominal 24 Volts. So someone may have mistakenly measured the current consumption at 24.0 Volts when the actual battery voltage is 30. The allowed range of supply voltage is 20.0 to 32.0, consistent with a military vehicle DC supply.
The current is interesting. The specified Tx current (3.5 Amps) is slightly greater than the fuse current (3.2 Amps) in the TM, indicating that two batteries are needed to avoid blowing the BA-5590 fuse. I have used a single BA-5590 without blowing it's fuse, but my Tx times have been very short and so maybe I was lucky with the slow blow aspect of the fuse.
The rechargeable BB-390 and BB-590 do not have a fuse and are capable of large surge currents so a single one would work fine. I had a BB-390, but it exploded during charging.
9 July 2004 - Test using prototype Battery Adapter based on two strings of 11 "AA" cells. When transmitting USB a small number of clicks can be heard in the H-250 handset indicating there are some voice peaks that are pulling the battery below 20 Volts, but when listening on the NRD-545 receiver the voice sounds normal. So the super caps may be the solution to providing high current peaks. Will test that shortly.
Note that when BA-5590 batteries are used, 2 of them are required, and in a similar way if 2 of my prototypes were used, then there would be no low battery warning and the battery life would be greatly extended. There are a couple of diodes that are a part of the battery charging circuitry in the CY-7875 that combine the two batteries. Each battery is connected in series for about 30 Volts and then the two physically seperate batteries are paralleled for more current capability.
|CY-7541 & CY-7875
side by side photo
CY-7541 Rechargable small Battery Box
Orig 16 Silver-Zinc 1.86 V cells (30 V)
4.8 AH (144 Watt Hr)
Battery Pack 1
Battery Pack 2
holds 2 each:
BA-5590 or BB-390 or BB-590
Battery Charging Circuit
2 each BB-590
The 2-pin connector is a MS3106E12S-3P.
The CY-7541 has no charging connector so this cable would be just the thing to charge one.
|This cable has alligator clips on the
input end, a network in line with the cable and the
Hughes box type 3 terminal connector that mates to
the DC input on the AM-6874. The network
consists of over voltage protection circuit and has
an external (Bussmann GMW-5) 5 Amp fuse.
The markings are:
Shrink label on cable: 87990 ASSY, 755002A1255, MFR 05869
This number matches the p/n in the manuals for the CX-13030 Bench Test Cable.
The network box:
87990-755002A1214-A, MFR 25232
White Wire going to Red alligator clip:
There are a number of options.
The radio has a 3/8-24 female thread. The AB-129 Spring Base and a 10 foot whip, the AT-271, goes above the spring base. There is a telephone type push to grab ground terminal right next to the antenna socket so a counterpoise can be used. The PRC-47 had the counterpoise wires as part of the base that held the radio up, but on the PRC-104 the counterpoise must be connected.
Fishing Pole Antenna
| AB-129 Spring
AB-129 has female 3/8-24 threads at the top and male 3/8-24 threads at the bottom.
It's needed to provide some "give" so that the thin walls of the AT-271 antenna don't "fold" when there is a strong wind or other movement.
is a vehicle whip that can be configured as a 16
foot or 32 foot whip.
is an NVIS antenna system origionally designed for
the PRC-47, but can be
used with many radios be means of adapters.
The AB-1241 patio umbrella base, hubcap base was designed for use with the PRC-104, but only using a very short coax cable (non 50 Ohm).
"AN/PRC-104 Ultra Lightweight Manpack Radio" Dec 1974 sales brochure I picked up at Hughes Torrance. "The AN/PRC-104 Manpack Radio is being developed by Hughes Aircraft Company, Ground Systems Group, Fullerton, CA for the U.S. Marine Coops under Contract N00039-74-C-0357." I think they were also working the the TPQ-36 and/or TPQ-37 mortor and artillery gun location systems.
There are no photographs in the brochure, only drawings. The actual PRC-104 looks different in a number of details that are both cosmetic and functional. For example the small battery box is shown with tapered lower ends, both on the cover and inside. The top of the small battery box is shown as a lid that can be opened to allow battery pack installation, but my small battery box has a removable end, not top. There is also an illustration of a chopper where the RT-1209 is located in the cockpit and the amplifier, whether 20, 100 or 400 Watts is mounted near where the HF antenna enters the chopper, about the middle. This implies that an extension cable could be used between the RT-1209 and an amplifier. Another illustration shows AM-6879 that is an audio amplifier, power supply and RTTY converter to be used for vehicle mounting, but not with the 400 Watt power amplifier that makes a GRC-193(). The description of the amplifier antenna coupler says it's a 30 Watt amplifier and the specifications table says 20 Watts output +/- 2 dB (20 Watts + 2 dB = 37 Watts)
The 20 Watt version is called the PRC-104, the 100 Watt base station the PRC-105 and the 400 Watt vehicle mounted system the AN/MRC-138.
The RT-1209 is said to be able to use CW keying at 300 WPM without spurious radiation, but the GRA-71 is not mentioned.
The Antenna Coupler has "a sturdy base for the portable 8-foot whip" which refers to the 3 meter AT-271 fishing pole antenna.. It mentions that both a whip and a coax fed antenna can be attached at the same time, allowing the operator to switch back and forth rapidly to select the best one.
This Dec 1974 brochure mentions that Hughes had already supplied "more than 5,000 AN/PRC-74 Manpack HF radios" for the U.S. Army. That 5,000 PRC-104s were being produced for the U.S, Marine corps and that the HC-191 was identical to the first article PRC-104 with the addition of AM capability for communicating with older military radios.
No where in this brochure do they use the terms RT-1209, AM-6874, AM-6879.
Training Course SS0716 - Single Channel Radio Operator , MOS31C Skill Level 1, Install, Operatre, and Perform Organizational Maintenance on Radio Sets AN/PRC-104 and AN/GRC-213, Part I
Training Course SS0717 - Unit-Level Communications Maintainer, MOS 31V Skill Levels 1 and 2, Install and Perform Unit-Level Maintenance, on AN/PRC-104(A) and AN/GRC-213
The 104B has an LCD display, built-in ECCM (i.e. frequency hopping) and the upper audio connector has been replaced by a 19 pin connector labeled CONT for Control.
3/4 View of RT-1209 showing the
interface connector to the AM-6874.
3/4 View of AM-6874 showing the
interface connector to the RT-1209
On the back of the AM-6874 is the
battery box connector.
There is a 48 pin connector that interfaces the AM-6874 and the RT-1209. This connector supplies DC power into the RT-1209 and from the RT-1209 the low level RF is supplied to the Amplifier Coupler along with digital frequency information to tell the amplifier coupler the radios operating frequency. The pins are designated using numbers at the start and end of 9 rows. In the center there is a hex depression with the corners lettered N, Z, Y, X, W, V.
The RT-1029 has two 4-40 tapped inserts on about 1 9/16" centers and the AM-6874 has a couple of 4-40 screws on about 1 9/16" centers. These could be used to hold a bracket with a mating connector to allow the two units to be separated, like in a helicopter as shown in the Hughes Sales Brochure.
Also see the RT-1444 below.
PRC-104B 160 M conversion overview
Posted by: "Peter Gottlieb"
Date: Sat Nov 22, 2014 7:08 pm ((PST))
So here's the latest. Two things need to be done in the 1209A RT to enable operation below 2 MHz:
1) The RT has harmonic filters which are selected by logic in a hybrid in the control panel. When the dial frequency is below 2 MHz none of these filters are selected and there is no path for the RF on either receive or transmit. The 2-3 MHz filter must be enabled to operate below 2 MHz; it is fine for 160 M use as it only drops off 1 dB at 1.8 MHz. It does, however, start to fall off a cliff below that.
2) The amp/tuner unit takes MHZ info from the RT and uses this to select ranges for inductance and capacitance. It makes this determination based on logic in a hybrid so cannot be changed. When it is told a 1 MHz range frequency is selected it doesn't operate properly (I did not investigate further as to precisely what it does). There is also logic in the tuner to give a continuous "out of range" error beeping when the frequency selected is under 2 MHz. I decided that rather than modify two devices I would simply modify the MHz information the RT sends to the amp/tuner so as to "fake it out." When a frequency in the 1 MHz range is dialed up I simply tell the amp/tuner it is in the 2 MHz range and the tuner operates in its highest capacitance and inductance range.
What I did was to lift two diodes on the flex board behind the front panel and attach a series of wires. I also picked up ground, +12 volts and the harmonic filter relay coil. Here's a photo of the wires: http://petergottlieb.com/images/prc104/DSC03758.JPG
I ran the wires into the compartment where the modulator PCB is as there is room under it for a small additional PCB with the needed extra components. For the moment, I put what I needed onto a protoboard so the wires are just hanging out: http://petergottlieb.com/images/prc104/DSC03761.JPG
You may wonder what I did in the circuit itself. I needed logic to change a 1 MHz BCD word to a 2 MHz BCD word and also drive an open collector transistor to pull in the filter relay when this is done. I went with Eugene Hertz's suggestion to use an EPROM. There are several things to consider:
1) Due to the diodes, which convert 12 volt logic to 5 volt logic, I needed two 100k pullup resistors on the lines I intercepted (1 and 2 MHz)
2) I used a CMOS EPROM, the smallest I had was a Fujitsu 27C64. Vast overkill, I'm only using 30 locations out of 8,192.
3) No 5 volts is available so I took +12.5 and used a 7805 to make my own. 6.5 is also available but that's a little tight for the old 7805. All I really need is a 78L05 because I'm hardly taking any current but I didn't have one laying around.
4) The open collector drive is very basic: an output of the EPROM drives a 2N2222 through a 1k resistor. It would probably be better to use a higher resistor but that's what was closest at hand. I bet driving that transistor is my biggest current draw.
How does it work? Here is a photo of my counter when in USB CW mode: http://petergottlieb.com/images/prc104/DSC03762.JPG
My frequency is pretty darn close (the counter is referenced to a Rb), something like 0.1 Hz low.
The last step will be to get a 78L05 and build this onto a small board and mount it under the modulator board.
If anyone wants the binary file for the EPROM and the wiring diagram, I'll be preparing those. It is also quite possible to build the logic with a few CMOS chips and it would work the same. Once I get everything finished I'll make a document and put it on my site for anyone to download and otherwise spread around.
There is one thing which is a slight hack, and that is that I don't stop operation below 1.8 MHz. However, the AM station I listen to for weather is there and with 50 kW the degraded sensitivity isn't a problem. If you try to transmit (why?) you will find the output power goes down dramatically below 1.8 MHz as transmit goes through the same filter as receive. I decided to leave that be as I don't have any intention to transmit there and with the power getting so low I'm sure it won't hurt the unit.
One note about the built in tuner: its configuration seems to be mostly designed to tune antennas which are capacitive, or shorter than what should be, such as the whip. My setup is inductive at those frequencies so it doesn't do well, but that has nothing to do with this mod.
The Antenna select switch has 3 positions
If the wrong External BNC antenna switch position is used you will get a 12 second tune tone followed by an error beeping tone.
- 9 to 16 foot Whip antenna, or a 1/4 wave long wire, where the coupler tunes the antenna.
- External antenna on BNC connector where the coupler tunes the antenna, like the AS-2259 with a non tuned BNC base and a short coax feed line. Could use a cable to seperate the RT-1209 from the AM-6874 so the AM-6874 would end up near the antenna feed point improving the antenna match and eliminating any coax loss. This might be a way around my current problem using the AS-2259 with the radio indoors (50 feet of coax away . . this does NOT work.)
- External antenna on BNC connector where the external antenna is near 50 Ohms impedance. No practical length limit on coax feed.
Then just turn the radio off, back on, set the ANT switch to the other BNC position, and key PTT.
Note: the sales brochure mentions that both the whip and a coax connected antenna can both be connected at the same time to allow switching back and forth to choose the best one.
The Hughes 3 contact CD power connector on the AM-6874 and a mating connector on a fabricated cable as used with the AM-7152.
3794941 AUTOMATIC ANTENNA IMPEDANCE TUNER, Lawrence R. Templin (Hughes), Feb 26 1974, 333/17.1 ; 324/619; 324/630; 324/650; 327/236; 333/17.3; 334/47
2 - 80 MHz
Calls:3835379 Detector Circuits for Signal Transmission, Lawrence R. Templin (Hughes), Sep 10 1974 - 2 - 80 MHz
2745067 Automatic Impedance Matching Apparatus, True (na)
3443231Impedance Matching System, Roza (Gulf Genereal Atomic)- analog motor
3509500 Automatic Digital Tuning Apparatus, McNair (Hoffman) - 2 -30 MHz based on MHz and 100 kHz dial setting
3281721Impedance Matching System, Clark (Sperry Rand) -
Calls:3919643 Phase Sensor Circuit, Lawrence R. Templin (Hughes), Nov 11 1975, 2 - 80 MHz
3020529 Reflected Power Alarm for a Variable Power Output Antenna System, Turner (Collins) - vacuum tubes
Calls:4857865 Self equalizing multi-stage radio frequency power amplifier, Arnold L. Berman, Carl J. Hahn, III, Marvin R. Wachs (Hughes), Aug 15, 1989
3366883 Automatic Broad Band VSWR Power Control Griffin (Avco) - turns down power if mismatched
3475703 Coarse Step-Fine Tune Automatically Tunagle Antenna, Collins motor analog
3786355 Radio Frequency Resistance Descriminator having Dead Zone Output Characteric (Cincinati Electronics) -
AT-271A 10 foot whip antenna (the same fishing pole antenna used on the PRC-25 & PRC-77)
AB-129/PR Antenna spring base
AB-1241 NVIS Ground Mount Antenna Base or T1995
AT-984 Fishing Reel Long Wire Ref =MCRP 3-40.3B Radio Operators Handbook, CH 4 - Sloping Antennas
AS-3683/PRC referenced in one of the Antenna Theory sub courses as working with SINCGARS and PRC-104, most likely an error since it's only a 2 foot tape antenna.
KY-872 leg clip Morse code Key NSN 5305-01-067-5388
CX-13030 Bench Test Electrical power Cable
CX-13031 Battery Extender cable
CX-13032 Battery Charger Power Cable NSN 5935-00-231-3180
CX-3515 Coax cable
CY-7542 Transit Case
H-250 Handset NSN 5965-00-043-3463
TM 11-5820-477-12 for the GRA-39 shows the Radio Set Control being used with the PRC-104 in a GRC-193A configuration, but it could be used to remotely control any version of the RT-1209().
Alice LC-2 Pack ComponentsThis PRC-104 was on a corner table at the 2004 meeting of the West Coast MRCG in San Luis Obispo
8465-01-253-5335 MIL-F-43833 81349 LC-1 Field Pack, Medium, Woodland
8465-00-001-6476 MIL-F-43834 81349 Cargo Support Shelf
8465-00-001-6477 MIL-S-43828 81349 Webbing Strap, 1” x 52”, Olive Drab
8465-01-073-8326 MIL-F-43834 81349 Pack Frame w/Straps
Following are replacement parts for the Pack Frame
8465-01-075-8164 MIL-S-43835 81349 Waist Strap
8465-01-151-2891 MIL-S-43835 81349 Frame Attaching Strap 1
8465-01-078-9282 MIL-S-43835 81349 Shoulder Strap, Right Hand
8465-00-269-0482 MIL-S-43835 81349 Shoulder Strap, Left Hand
The RT-1209 and AM-6874 when connected toghther have a front panel that's 12¼" wide and 2¼" high. The depth depends on which battery box is being used. With the CY-7875 (dual BA-5590) battery box the radio is 13½" deep. With the CY-7541 (Samll rechargable) battery box the deepth is 10½". The small battery box version fits with some closure at the top, but even the large battery box version fits the Field Pack well.
- RT-1209 Receiver Exciter
|Loop current metering tip
Select 60 ma or 20 ma, TTY On - Off - Spkr On Handset
Adjust loop current Audio
TTY Key binding posts, Squelch: Off - Max 3 Amp Fuse
DC Loop binding posts
|J6 female 19 pin RT
& PA Ctrl
Spare 3 Amp fuse J7 Type-N Jack RT R.F.
||Publication Title (partial)|
|059423||TM 11-5820-922-40-1 A||
AMPLIFIER-CONVERTER, AM-6879/URC (NSN 5820-01-070-1950)
|059525||TM 11-5820-922-40-2 B
AMPLIFIER-CONVERTER, AM-6879/URC (NSN 5820-01-070-1950)
- CU-2064 Antenna Coupler Harris
- AM-6545/GRC-193 Amplifier 100 or 400 Watts Harris
- AM-6545A/GRC-193A Amplifier 100 or 400 Watts HarrisNSN 5820-01-186-3699??
- MT-6232 Mount
- Whip Antenna
CW-206 Bag, High Voltage Protection Plastic Antenna sleeve, 2 ea. tie down ropes, safety tip, 3 ea. MS-116, 1 ea MS-117 and 1 ea. MS-118 mast sections and the AB-652/GR antenna base.
- RF-4032 Tactical Antenna Siting Kit for up to 200 feet remote antenna location.
- Training Course SS0710 -Single Channel Radio Operator, MOS 31C Skill Level 1, Install, Operate, and Perform Organizational Maintenance on Radio Set AN/GRC-193, Part I
- Training Course SS0711 - Unit Level Communications Maintainer, MOS 31V Skill Levels 1 and 2, Install and Perform Unit-Level Maintenance of AN/GRC-193A Radio Set (IHFR), PART IIRT1209 with Power, Control & RF Cable A3210524. I was hoping to find a similar cable that mates with the AM-7148 to allow using the Power Amp with other radios.
- RT-1209 Receiver Exciter
- AM-6879 Audio Amplifier-RTTY Converter
- CU-2064 Antenna Coupler Harris
- AM-6545A/GRC-193A Amplifier 100 or 400 Watts HarrisNSN 5820-01-186-3699
- MT-6232 Mount
- TM 11-5820-924-10-HR
- TM 11-5820-924-13
- TM 11-5820-924-24P GRC-193A
- TM 11-5820-1045-40P GRC-193B(V)1
- TM 11-5820-1045-20P GRC-193B(V)1
- MK-2462/GRC-193A Installation Kit, Cargo Truck 1 1/4 Ton, 4x4 M882 or M1008A1 CUCV
- Mk-2458/GRC-193A Installation Kit, Cargo Truck 1 1/4 Ton, 6x6 M561 Gama Goat
- Mk-2461/GRC-193A Installation Kit, Utility Truck 1/4 Ton, 4x4 M151, M151A1 or M151A2 (CJ5 Jeep)
- Mk-2460/GRC-193A Installation Kit, Personnel Carrier, Full Tracked, M113A1 & Carrier Command Post - M577A1
- Mk2451/GRC-193A Installation Kit, HMMWV, Car Carrier M998, M1038
TM 11-2300-475-13&P-6TM 11-5820-921-40-1
|The GRC-213 is VRC-12
and the Mount fits MT-1029 hole pattern
connector on rear panel
DescriptionThere are two functional additions to the PRC-104 to make a GRC-213.
First the AM-7152 adds audio amplification, noise squelch and a VIC-1 connection. Note that the PRC-104 does not have any squelch at all, so this is a big improvement. The AM-7152 also does some DC power conditioning. Not sure what it all is, but there are some very large capacitors in the box. The PRC-104 is designed to run from a BA-5590 which starts out at 30 Volts and goes down. A military vehicle "24 Volt" system might be anywhere between 20 and 30 Volts, so there may or may not be active voltage regulation.
FM 24-19 Chapter 1 shows a retransmission system based on the GRC-213 and VRC-12 series radio, so it appears the main reason the GRC-213 was built is for retransmission applications. In Fig 1-20 they are showing the AM-1780 and the C-2299 and one C-2298 connected to J504, i.e. a commander's connection.
This system was designed to be VRC-12 Series compatible. The mount bolts to the same plate that supports the MT-1029, the VIC-1 and DC power in and out connections are the same as on the MT-1029. The LS-454 is a VRC-12 Series speaker. Any vehicle setup with an RT-246, RT-524 or PRC-25 or PRC-77 on the AM-2060 could easily be converted to use the GRC-213 or become a cross band retransmission system linking VHF low band with HF.
As far as I can tell all the other systems based on the RT-1209 are NOT VRC-12 compatible, i.e. they do not have the VIC-1 interface. This means that they can not easily be used for retransmission. Also note that for retransmission you need squelch to generate the retransmission PTT output, so other audio amplifiers that do not have squelch can not be used for retransmission.
Second the SA-2365 Antenna switch box which is part of the MT-2154 mount assembly that comes with the install kit goes between the existing PRC-104 antenna BNC connector and the actual antenna in use. The Antenna Loading Switch has positions for 2 - 10 MHz, 10 - 30 MHz to an external 15 or 16 foot whip or a Dipole. It's designed to supply some simple fixed tuning (maybe an RF cap.) for a 16 Foot long AT1011 type vehicle antenna. There are two connectors on the rear of the SA-2365, J203 is a BNC(f) and J202 is a Type-N(f). J202 is used to connect to the 15' whip using as short a coax cable as is practicable.
The two ground straps on the shock mount connect to the PRC-104 and to the AM-7152 using a couple of 6-32 x 0.5" screws.
"Vehicle-mounted version of AN/PRC-104 HF manpack radio. Three subsystems: receiver/exciter, power amplifier/antenna coupler, and vehicle mount unit. Vehicle adapter designed to fit footprint of standard VHF/FM series of equipment: VRC-12, GRC-46, RT-524, etc. Power connections and audio intercom equipment fully compatible with FM equipment.
AN/GRC-213A is newer version measuring 406x207x292 mm, weighing 19.5 kg. Data rate of 300 wpm, TTY (FSK) or burst CW. AN/GRC-213B is vehicular or base station version with power output of 100 or 400 W PEP or average.
AN/GRC-213 entered production in 1983 for US Army. October 1983, US Navy, acting as procuring agent, placed $45M order for 1,544 radios. Sept 1987, 448 AN/GRC-213As ordered; in 1988 an option for 94 more was exercised. Production has been completed. " From the Joint Tactical Radio System FACT SHEET.
Retrans Ctrl Box
Retrans Ctrl Box
| A simpler way to get a
RETRANS system is to just use the C-2299 directly
between the two radios (without any AM-1780).
When the C-2299 has RETRANS set to OFF the other switch selects RT 1 or RT 2 for connection to the handset on the C-2299 providing remote control of two RTs or RETRANS capability. This would allow the GRC-213 to be interconnected with a VRC-64.
With the GRC-213 connected to RETRANS with the PRC-77/VRC-64 I could carry a PRC-68 family VHF low band radio around my property and work stations on HF via the GRC-213. Note that RETRANS works both ways so that I could transmit to and receive from the HF station on the VHF low band radio.
14 July 2004 - It's working. When the squelch opens on either the HF or VHF radio the other radio has it's carrier keyed. The audio from the BC-611 is weak in SSB receiving mode, but it's there and can be understood.
Note the radio connected to C-2299-J701 is supplying power the the mike amp in the C-2299. So if you want to use a handset connected to C-2299-J703 or J704 the radio connected to J701 needs to be powered. There is no DC path from J702 to the mike amp.
For this test I have disconnected the J-3514 from the MT-1029 and am connecting the C-2299 directly to the MT-1099. Also the CX-13065A cable has been disconnected from the AM-2060 and PRC-77 and a CX-4655 interconnects the AM-2060 and PRC-77. Making this an ordinary VRC-64 (non VINSON) VHF radio set.
The GRC-213 is connected to the T2FD antenna and the PRC-77 is connected to the OE-254. The NRD-545 is using a VHF Radio Shack scanner monitor antenna and the BC-611 is using it's built in whip.
I'm setting the PRC-77 to SQUELCH mode, not RETRANS, since RETRANS is for use with the MK-456. This system uses the squelch breaking to trigger RETRANS through the VIC-1 type connection.
- Audio from Radio
Speaker - Maybe to LS-454 (pins A & E)
M55181/5 Type Connectors
J101 - 4 Plug receptacle - DC Battery In
J102 - 18 Socket receptacle VIC-1 Interface
J103 - 4 Socket receptacle - DC Battery Out
J104 - 8 Socket receptacle - DC to Radio
Vehicle Whip -? Details
AT-1011 16' or 32' Whip
Conditioned DC Power Cable
The end mating to the AM-7152 is a standard VIC-1 type MW10M(M)B II connector with 9 male pins.
The other end is the Hughes special DC power connector box that mates to the AM-6874 Amp Coupler.
Shrink Label reads:
ASSY 1623814, MFR 05869
TM 11-5820-923-12 GRC-213
TM 11-5820-1047-12 GRC-213A
TM 11-5820-923-20P GRC-213
TM 11-5820-1047-20P GRC-213A
TM 11-5820-923-34P GRC-213
Installation & Operation Slide Show with sound
FM 44-18 Chapter 4 - Communications (Stinger Platoon Radios)
FM 11-32 Chapter 6 - IHFR
GTA11-03-031.pdf - Operating Procedures IHFR Radio Set GRC-213
TM 11-5820-923-40 Installation Kits:
Mk-2442/GRC-213 Installation Kit Armored Personnel Carrier M113A1
Mk2443/GRC-213 Installation Kit, Utility Truck M151A1
Mk-2444/GRC-213 Installation Kit, Cargo Truck M561
Mk-2445/GRC-213 Installation Kit, Command Carrier Post M577A1
MK-2446/GRC-213 Installation Kit Truck M882 or M1008A1 CUCV
NSN 5820-01-189-9789 consists of:
MOUNTING BASE-Provides a shock resistant mount for the AN/GRC-213NSN 5820-01-189-9790
SWITCHING UNIT-Provides impedance matching between AN/GRC-213 and the antenna and enables the AN/GRC-213 to tune to the antenna ANT SWITCHING UNITS A-2365/GRC-213 , DSGN ACT: 80063 , ITEM NO. A3023160 , MFR 54736 , SER NO. 429 US , SPEC: A3023163
ANTENNA-Transmits and receives rf signals ( COMPLETE ANTENNA IS OVER 16 FEET HIGH)
ANTENNA CABLE-Connects the antenna to the switching unit
ROPE-Secures the antenna to the vehicle
ROPE CLAMP-Enables the rope to be attached to the antenna
BATTERY POWER CABLE-Connects the AN/GRC-213 to 24 V dc vehicle battery power
POWER CABLE-Connects the AN/GRC-213 to 24 V dc vehicle power
Antenna Base AB-1322/GR
nuts bolts and washers , ground strap , brackets , antenna sections , antenna tip ball
Mk-2447/GRC-213 Installation Kit General Purpose wheeled or tracked Vehicles
Mk-2542/GRC-213 Installation Kit Cargo Troop Carrier M998, M1038 HMMWV
----------------------- Bottom row:
Second VRC-83 Aircraft RadioThe same as the first VRC-83 and it's KY-57 is just above the radio. This one is dedicated to VHF-AM operation so only needs an antenna that covers that band.
KY-57 for VHF Low Band RadioThe RT-524 and first generation SINCGARS radio, the RT-1439 need an external KY-57 for voice security. The newer SINCGARS RT-1523 has internal voice crypto and so does not need that KY-57.
H-250 Storage Box above KY-57"That was a handmic box. We stored the H-250's in there so they wouldn't bang around. Other times it was to hold the instruction manual to the pallet. Not quite water tight but it kept a majority of the crud out."
Army VHF Low Band RadioFirst generation systems used the RT-524 radio on the MT-1029. This is a VRC-12 series radio and has no remote control capability. The second generation systems use the RT-1439 first generation SINCGARS radios. I think in the dual radio mount allowing one of them to use an external RF power amplifier. These radios have limited remote control based on the audio tone system which can select a channel number but not setup a channel frequency or other channel setup parameters. The various newer RT-1523 versions have the same remote control capability but also include built-in voice security and so the third KY-57 is not needed.
Different versions of the GRC-206 system have used the different Army VHF-FM radios starting with either the RT-524 or the 10 channel RT-246 (it's not clear to me which) then the RT-1439 that has 6 channels as does the RT-1523. The operator can select which of the preprogrammed channels to use. The implication is that there's some commonality in the channel selection method for the VRC-12 series radios and the SINCGARS radios.
But the C-2742 used with the RT-246 uses a very basic one wire per channel type control whereas the SINCGARS radios use serial data stream via an audio modem. So there must have been a serial to parallel converter in the GRC-206 system when (if?) it was used with the RT-246. If that's the case then the serial protocol in the SINCGARS radios may have been made to the the same one?
--------------------------- Control Box
C-11166 Two Operator Control BoxIn the lower left and lower right corners are duplicate Audio connectors and a radio selector switch allowing each opertor to choose which radio he will use. It can be mounted between the seats in a vehicle or remotly located using fiber optic cable.
From the t2k Yahoo gaming group:
The AN/GRC-206 (V)1,3,5,6
V1 is model with no crypto and no Have Quick, can be sold to foreign governments
V3 has crypto KY-57 x 3 and KY-65 x 1 and SINCGARS VRC-83 are have quick II (TOD cable)
V5 replaced SDU, PDU, RSC, KY-65 and VRC-46. KY-65 replaced with KY-99 and VRC-46 replaced with SINGARS long range short range combo.
V6 replaced VRC-46 (rt 524 or 246) with dual SINGARS long short combo.
GRC-206(V)1 can be fitted with KY-57 (VHF & UHF radios) or KY-65 COMSEC (HF radios) devices; the GRC-206(V)2 cannot.The GRC-206 mounted in the M-998 hummer is the way we use them for forward air control. In the hummer it is called the MRC-144. The 206 replaced the 155/MRC-107 and MRC-108 (old radio systems).
The 206 is comprised of:
- Top left corner facing the pallet. VRC-83 VHF/UHF AM(RT-1319B/PRC-113 withAM 7148? amp) power output will be 2, 10 or 30 watts. 30 is normal for vehicle ops. Frequency range is 116-149.975 and 225-399.975 Note, in this position it only works in UHF 225-399.975 mode.
- Top right corner. URC-113 HF SSB (RT-1209 with 1444 remote mated with AM -7148 amp). Power will be 150 watts peek single side band. Frequency range is 2-29.99999
- Bottem Left corner is the same as top left corner, except radio only functions in VHF AM mode.
- Bottom Right corner, (currently almost all radio systems are V6's) two SINGARS FM radios. One in bottom position is hooked to amplifier providing @50 watts, top radio is for manpack operations but can be used as the short range radio with hi power being @4 watts. Frequency range is 30 to 87.975 MHz
From a CBD RFQ some GRC-206 parts:
5821-01-408-9471RY CONTROL RADIO SET, P/N, 729450-801
5820-01-411-2903RY CONTROL RADIO SET, P/N 724760-801
5895-01-409-0740RY PANEL CONTROL, RSC, P/N 729456-801
5895-01-408-9101RY CASE, RSC, P/N 729455-801
5998-01-411-2901RY SDU TI AUDIO BOARD, P/N 729446-801
- GRC-206(V)3 Comm Pallet. On/off road tactical communications central replaces MRC-107/8. Used by TACP, ASOC, CCT, Combat Comm, and WICP. The AN/MRC-144 is a mobile HF/VHF/UHF HAVE QUICK II capable communications facility (AN/GRC-206(V)3) mounted in an M-998 Highly Mobile Multi-Wheeled Vehicle (HMMWV).
- The communications component of TTCS is an AN/GRC-206 (V4). The primary power source is the MEP-802A diesel generator. It can also be converted to a portable battery powered manpack system.
- GRC-206(V)5 Phase I. Integrates SINCGARS and ANDVT into the GRC-206(V)3. Radios are funded GFE. Includes HF automated link establishment (ALE).
- GRC-206(V)5 Phase II. Continuation of SINCGARS and ANDVT integration into the GRC-206(V)3. Radios are funded GFE.
- GRC-206(V)6 SATCOM. Add enhancements to the UHF DAMA SATCOM radios and integrate into the GRC 206(V)5 pallet. Radios unfunded GFE.
- Next Generation Comm Pallet. Upgrade GRC-206(V)6 pallet to include all similar radios capable of Multiband and Multiwaveform communications.
The AS-3588 is the large antenna that is used with the GRC-206 and mounts on a vehicle and covers both the VHF-AM and UHF-AM aircraft radio bands.
System NumbersNSN: 5985-01-153-7786 - this may be the basic GRC-206
Green = Have
Red = Want
The last digit in the p/n dash seems to be the system version number:
GRC-206(V)1 p/n-801 No Have Quick
GRC-206(V)2 p/n-802 No Have Quick
GRC-206(V)3 p/n-803 Have Quick I
GRC-206(V)4 p/n-804 Have Qucik II?
31R2-2GRC206-1 Operator's Manual non Have Quick (V)1 706167-801, (V)2 (707167-802)
31R2-2GRC206-1-1 Operator's Manual VRC-83 Have Quick Supplement (V)3 706167-803 )
Incomplete without 31R2-2GRC206-131R2-2GRC206-1-1 Operator's Manual VRC-83 Have Quick Supplement (V)4 707167-804 )
1 April 1983 no changes
31R2-2GRC206-1-2 Operator's Manual _______ Supplement (
31R2-2GRC206-1-3 Radio Communications System AN/GRC-206(V)6 Supplemental Operator's Manual p/n 707167-600
Incomplete without 31R2-2GRC206-131R2-2GRC206-12 Depot Maintainance Instructions w/IPB (707167-80, 707167-802 )
covers the VRC-91A SINCGARS replacing the RT-246 & KY-99A replacing the KY-38
Includes schematics for the SDU, PDU, RSC FM Bite, R-1444 interface.31R2-2GRC206-12-1 Supplemental Maint Man (707167-803 , 707167-806)
31R2-2GRC206-1TP-1 Operator Instructions
31R2-2GRC206-1TP-2 Operator Instructions
31R2-2GRC206-2 Intermediate Maint Man w/IPB (707167-801 , 707167-802)
31R2-2GRC206-2-1 GRC-206(V)3 Intermediate Maint Man Supplement (707167-803)
incomplete without TO 31R2-2GRC206-231R2-2GRC206-2-1 Intermediate Maint Man ______ Supplement (707167-804)
1 April 1992 no changes
31R2-2GRC206-2-2 Intermediate Maint Man 407L Supplement (31R2-2GRC206-2-3
31R2-2GRC206-2-3 Maintenance Instructions with Illustrated Parts Breakdown,
Intermediate,31R2-2GRC206-12 Techincal Manual,
Radio Communication System AN/GRC-206(V)6 p/n 707167-600
incomplete without TO 31R2-2GRC206-2-1
covers the VRC-91A SINCGARS replacing the RT-246 & KY-99A replacing the KY-38
Maintenance Instructions with Illustrated Parts Breakdown (IPB),31R2-2GRC206-12-1 Supplemental Techincal Manual,
Radio Communication System AN/GRC-206(V)6,
31R2-2GRC206-12-2 Supplemental Techincal Manual,
31R2-2GRC206-12-3 Supplemental Techincal Manual,
Maintenance Instructions with Illustrated Parts Breakdown (IPB),31R2-2GRC206-22 AM-7148 Amp-Coup Depot Maint Inst w/IPB (622-6147-001)
Radio Communication System AN/GRC-206(V)6,
details on the RFO
NSN: 5985-01-149131R2-2GRC206-2TP-1 Intermediate Maint Man w/IPB
15 Jan 1987, change 3: 22 Dec 2000
31R2-2GRC206-2TP-2 Intermediate Maint Man w/IPB
31R2-2GRC206-2TP-4 Intermediate Maint Man w/IPB
31R2-2GRC206-503 AN/GRC-206(V)5 SINCGARS/ANDVT
31R2-2GRC206-503C N/GRC-206(V)5 SINCGARS/ANDVT
31R2-2GRC206-504 --- title not avail---
31R2-2GRC206-6WC-1 Scheduled Periodic Instpection (V)1 (707167-801)
31R2-2GRC206-6WC-1 Scheduled Periodic Instpection (V)2 (707167-802)
31R2-2GRC206-6WC-1-1 Scheduled Periodic Instpection (V)3 (707167-803)
31R2-2GRC206-6WC-1-1TP-1 Scheduled Periodic Instpection
31R2-2GRC206-6WC-1-2 Scheduled Periodic Instpection 407L Supplement
31R2-2GRC206-6WC-1-3 Scheduled Periodic Instpection Workcards
Radio Set AN/GRC-206(V)631R2-2GRC206-6WC-1TP-1 Scheduled Periodic Instpection
31 Aug 1999
31R2-2GRC206-6WC-1TP-2 Scheduled Periodic Instpection
31R2-2GRC206-7 Installation Manual
Mounting the AN/GRC-206(V)3, AN/GRC-206(V)5 or AN/GRC-206(V)631R2-2GRC206-504 Integration of AN/GRC-206(V)6 SINCGARS/ANDVT
Radio Set into the High Mobility Multipurpose Wheeled Vehicle (HMMWV)
1 June 1999 Change 2
31 Aug 2000
Kit NSN 5820-01-127-3486 p/n 707167-806
How to upgrade (V)3 to (V)6TO 31Z1-407-06 Technical Manual
Depot, Intermediate & Organizational Maintenance
Work Unit Code Manual
407L Tactical Air Control System
16 Nov 1989 change 13
PRC-104 (RT-1209)31R2-2PRC104-2 Field Maint Inst
31R2-2PRC104-2-1 Supplemental Operation & Maint (RT-1444?)
31R2-2PRC104-4-1 Supplemental IPB
35C2-3-385-11 MEP-025A Gas Gen
RT-1319B VHF 7 UHF AM Aircraft radio
Universal Radio/Remote System Control URSC (guess at words for URSC)
C-11166 2 Op Ctrl Box - has display of the frequency for the HF, VHF, UHF radios and ability to set freq.
Photo by Mike Murphy -U.S. ISSUE COMMUNICATIONS EQUIPMENT AND RELATED ITEMS
Signal Distribution Unit SDUC11169 - connects to radio. Can link to the C11166 using fiber or metalic cable.
This is the "SDU" that matches the label on the O-1814.
Photo by Mike Murphy -U.S. ISSUE COMMUNICATIONS EQUIPMENT AND RELATED ITEMS
Power Distribution Unit PDUSB-4151 (Switch Breaker?)
DC power control box.
Photo by Mike Murphy -U.S. ISSUE COMMUNICATIONS EQUIPMENT AND RELATED ITEMS
Reference Frequency Oscillator RFO
O-1814 Rubudium Frequency Standard and Time Of Day Clock.
Has it's own web page.
Available from Mike Murphy.
M455-1 Power Supply
I think this is a dual input supply that accepts world wide AC power (99 - 262 V @ 47 - 440 Hz) as the primary source and if there's no primary source uses a secondary 18 to 40 V vehicle source.
The outputs are:
#1: 20 - 30 VDC @ __?__ Amps
#2: 8 VDC @ __?__ Amps
#3: 20 - 30 VDC @ __?__ Amps
Photo by Mike Murphy -U.S. ISSUE COMMUNICATIONS EQUIPMENT AND RELATED ITEMS
Note the J1 connector is to supply 8 VDC which is the voltage needed for the PSG-9 Handheld Terminal Unit (HTU) and other small military message computers.
MT-6250B/GRC-206The photo shows a AM-7239() Dual radio adapter/power supply with the early full size RT-1523 SINCGARS radios. The photo at the top of the GRC-206 section shows a single RT-524 VRC-12 Series radio. The AM-7238 RF Amp is just to the left.
The HF radio is the PRC-138 which has ALE capability. Don't know if the power amp is fast tuning or if it needs to work into a 50 Ohm antenna for ALE.
Item Name: Mounting Base, Electrical Equipment
Description: A tray or racklike item designed to provide a supporting surface to which electrical/electronic equipment may be secured when installed in aircraft, vehicles, or other types of mobile equipment. It may be equipped with shock or vibration isolation devices and/or wires, cables, terminal boards, connectors, etc. Excludes BASE, ELECTRICAL EQUIPMENT RACK and MOUNT, RESILIENT. See also RACK, ELECTRICAL EQUIPMENT.
Commercial and Government Entity Code (Supplier Data):
9438 US Hwy 19 N. #311
Port Richey, FL 34668
Ph. (727) 619-7700
Fax. (727) 255-5042
37695 RAYTHEON COMPANY
1010 PRODUCTION RD
Fort Wayne, IN 46808
Reference Numbers (Part Numbers):
Weight Minus Equip 20 Pounds
VHF-AM & UHF-AM Antenna
8 Nov 2007 GRC-206 at Mike Murphy's SurplusHe has set a PRC-138 in the upper right corner instead of the HF radio.
In the lower right he has set a couple of RT-1523 SINCGARS radios, but without the A/PS & Mount.
This is close to a GRC-206(5) system but the O-1814 was only in the GRC-206(3) system.
Raytheon Systems Company, Fort Wayne, Ind., is being awarded a $24,000,000 firm-fixed-price contract to provide for various quantities of components for the AN/GRC-206(V)4G communication system applicable to a range of ground vehicles, including the High Mobility Multipurpose Wheeled Vehicle and the M113 Armed Personnel Carrier. This effort includes support services, site survey, installation services, technical support and data. This effort supports foreign military sales to Greece and Jordan. There was one firm solicited and one proposal received. Expected contract completion date is ten each per month starting 12 to 14 months after receipt of order. Solicitation issue date was Aug. 6, 1998. Negotiation completion date was Dec. 9, 1998. Sacramento Air Logistics Center, McClellan AFB, Calif., is the contracting activity (F04606-99-D-0018).
ROMAD - Radio Operator Maintainer And Driver - Tactical Air Control Party (TACP) "Death on Call"
RT-1444 Remote control add on
AM-7148/GRC-206 150 Watt amplifier coupler (NSN) 5985-01-149-1437,
TO 31R2-2GRC206-22 Maintenance Instruction with Illustrated Parts Breakdown, Depot, Amplifier-Coupler, AM-7148/GRC-206, Part No. 622-6147-001, NSN 5985-01-1491, 15 Jan 1987, Ch 3 - 22 Dec 2000 + some hand changes. Need to study this to see if there's any RT-1444 information.
GRC-206 Fact Sheet.doc -
18 Pin J1 Interface connector
Install RT-1444 between Panel and Chassis of RT-1209
6-32 Pan head Philips screw self capture longer than 2.53" (not a 2.5")
Notice connector on RT-1209 chassis for amplifier.
The RT-1444 remote connector is on the oppsite side.
The long screws installed to hold RT-1444.
Now to remove them all and put on the flat washers.
I have some extras let me know if you want to buy some.
RT-1209 + RT-1444 + AM-6874
Wanted to see if the AM-6874 can still be used when the RT-1444 is fitted, and the answer is yes.
The following entry was found on Commerce Business Daily:The RT-1444 is a remote controllable version of the manually operated RT-1209. Note that the PRC-104A,B and C have built in remote control capability by means of the CONT connector located above the the single AUDIO connector. The unit pictured above is inserted between the front panel and the main body of a RT-1209/PRC-104 to make the resulting radio into an RT-1444/PRC-104. J1 is the 18 male pin ITT Cannon connector that has a 16 wire ribbon cable connecting to it. Most of the box is hollow and from the cavity there is a ribbon cable with a 18 + 17 + 16 three row "D" shaped connector with 51 male pins. On the other face there is a similar 51 pin connector with sockets. Thus the RT-1444 can be inserted between the front panel and the RT chassis. There are a couple of multilayer printed circuit boards and a number of large ICs, probably a microprocessor, RAMs and PROMs.RT-1444/URC
Jan 2009 - The Remote was made to allow the RT-1209 to be used with the GRC-206 (URC-113 uses the AM-7148 RF Amp) or the GRC-193 (uses the AM-6545 RF Amp). In either case the RF amp needs the MHz frequency information from teh RT-1209. Also the GRC-206 allows remote setting and readback of the radio frequency. Later GRC-206 systems used the PRC-138 to get ALE capability and the adapter box similar to the RT-1444 that had ALE capability was aimed at this application, but I don't think it was choosen.
The R-1444A has had the internal PCB removed and replaced with a new set of boards and has ALE capability. The 1040 upgrade kit was sold by NSG Datacom (took over the Frederick Electronics product line) to the Sweedish Army for use in PRC-104 systems. I don't think the AM-7148 RF Amplifier/Coupler can tune the antenna fast enough for ALE, although if used with a matched antenna, like the B&W terminated folded dipoles might work if the band switching time is short enough.
The RT-1444 shown in the above images is labeled:
Ser: AE0283 812130-801
F04606-81-C-0017 Mfr: 37695
Magnavox U.S. Ft. Wayne, Ind
The Tobyhanna Army Depot Process Tag has:
National Stock Number: 5895-01-140-8315
Serial Number: AE0283
the inspection stamps are dated 18 Nov 99
and on the back:
Tested/Repaired in Accordance with:
31R2-26RC206-2 Table 5-1A
The Faraday bag is labeled:
5895 01 140 8315
CAGE p/n 812130
MGX-12/99 B 1 ea.
The outer cardboard box has the same info and TYAD RWKD & TSTD 11/99
It looks like the contact was in 1981 and then in 1999 Tobyhanna Army Depot made some modification, tested and repacked the unit.
Item 0001 NSN 5895-01-140-8315ZX P/N: 812130-801, INSTALLATION KIT FOR RT-1444.
CASE MODIFICATION FOR RT-1209. E/I AN/GRC-206(V). ECO 87C0508 APPLIES TO THIS ITEM.
So maybe the modification done at Tobyhanna Army Depot was something to support the use of the RT-1444 with the GRC-206 system.
J1 Pin OutMating cable connector is NOT MS3116F-14-18S. This connector does not work since two of the standard keys do not match the RT-1444. Some work with a Dremel grinder on the connector (removing the two narrow out of place keys) will NOT allow it to fit.
The correct mating connector may be the MS 27484T-14F-18S.
The connector for the MT-6250B/GRC-206 is a MS 27484T-14B-18S.
But the rotation of the main key (the minor keys remain the same w/respect to the pins is the "A" rotation. That means the part number ends with A such as:
See the Part Builder.
# following a signal line means the inverted (not) form of the signal. This was probably done to make the logic simpler.
Remote Select #
RT-1444 Status #
RT-1444 Control #
RT-1444 Clock # ?
DIP pins 1, 9, 10 & 11 are connected toghther (grounds).
Connector pin M seems to be out of order with the DIP numbering system so I ass-u-me that DIP pin 5 is the RT-1444 Clock# signal that my first source showed on connector pin U.
Pin R - Remote Select - probably chooses between an active front panel and remote control. Since this is the inverted signal, an open means not-remote and a grounded pin means remote. That way when no cable is connected the radio works from the front panel. I was told that the remote cable just has a jumper between "R" and ground. A better way would be to allow a remote computer decide to allow the radio to be in remote or local mode.
Pin L (clock) & Pin U (/clock) probably are for serial data streams "Control" and "Status", where "Control" most likely means commands to the RT-1444 and "Status" means data coming from the RT-1444, like frequency, etc. and maybe error codes.
The other connectors that interface external to the RT-1444 are the male and female 51 pin interfaces to the RT-1209 front panel and the RT-1209 main chassis.
1040 ALE Modem would require the RT-1444 remote so that the frequency of the PRC-104 could be controlled. Or maybe the other adapter that's similar to he RT-1444 which is an ALE adapter?
It may be possible to send and receive ALE signals, but without changing RF frequency using the Data T/R mode. See photo army mars.
TM 11-5820-40-1 Table 1-4 Cable W2 RT Control has pinout information that's related, but it uses a parallel (one wire for each front panel button) protocol, meaning that somewhere else there's a serial/parallel converter.
This is a combined RT-1209 and the RT-1444 all in one box so on one side it has the connector to go to the RF Amp and on the other side the connector for the URC-113/GRC-206. It has the same battery box connector on the bottom to make a PRC-104 manpack radio.
Collins Telcom Products Drv
Cedar Rapids, Iowa U.S.A.
Controls and IndicatorsTwo 6-pin U-229 type AUDIO connectors
Function Switch: OFF, RCV, MAN, A, TEST, unmarked, unmarked, unmarked
Left-Right navigation knob (continuous rotation in steps)
Up-Down navigation knob (continuous rotation in steps)
VOL knob in steps
LIGHT momentary push bottom
LCD with labels a top: VOL, MODE, FREQ, SQL, PWR
If you have any info on this please let me know.
The date codes on most of the chips show 1982.
Fig 1 Front Panel
The Function switch continues to turn past TEST
a few clicks (maybe defective) Pressing LIGHT
turns on a couple of lamps.
Fig 2 Left Side w/ URC-113/GRC-206 Remote conn
Fig 3 Right Side w/ RF Amp-DC power conn
Fig 4 RT-2000 with AM-6874 Front
Fig 5 RT-2000 with AM-6874 back
Fig 6 Inside bottom of digital board
Fig 7 Top of digital board
Fig 8 Top of 2-layer stack
Fig 9 Bottom of 2-layer stack IF subsystem
McCoy 42.995 MHz can osc & Collins Mech Filter
Fig 10 Top of bottom board
Power supply to the front & audio to the back
Maybe RF in central can?
The bottom board can be lifted out.
Fig 11 Top of digital board showing clipped resistor
just above notch at bottom center of photo.
-------- the above radio is dead ----- the below radio receives but does not transmit ------
Fgi 1 Function: Test
Volume: bar graph
Mode: USB, UD = LSB/USB, UD/LD
Squelch OFF, CW
Fig 2 Function: A
Full Vol, USB, 29.0000, On, 3
Fig 3 Function: ?
squelch on, pwr: 3
Fig 4 Function: ?
Squelch on, pwr: 1
Fig 5 Function: Man
USB, 29.000, On, :
Fig 6 Function: Man
Full Vol, USB, 29.000, Off, :
Fig 7 Function: Man
Full Vol, USB, 2.0000, Off, :
Fig 8 Function: RCV
FM 24-19 Section IV has info about using the KY-65, 2 ea. BA-1372 HUBs, CX-13168 cable between the RT-1209 upper AUDIO connector and the KY-65 RADIO connector. Z-AKE is an AC/DC power supply for the KY-65. CX-13211 cable between the KY-65 AUDIO connector and the AUDIO connector on the AM-6879 Ampl;ifier-Converter. Handset to AUDIO connector on KY-65.
In a vehicle installation the cable from the J-4885/GRC Junction Box goes to the speaker connector on the Amp-PS. The H-250 handset connects to the J-4885 HANDSET connector. An LS-454 Speaker connects to the Speaker connector on the J-4885
Less than 10.2 volts causes a battery fail condition. This is consistent with a 10 to 15 Volt range for a "12 Volt" supply.
The KY-65 uses the Parkhill algorithim. If someone talks too fast then the message gets garbled. This is because the output needs to have a narrow (3 kHz) bandwidth to work with HF radios. A fast talking person will exceed 3 kHz bandwidth.
It think this system divides the 300 to 3,000 Hz voice band into 9 sub bands each 300 Hz wide. The signal in any of the 9 bands can be changed to any of the other bands either as is or inverted. So there are 18 things that can be taken 9 at a time or 18!/(18-9)! = 17.6 billion. Note that the key is a fixed permutation of the sub bands and does not change with time like the more modern voice encryption systems, so no date - time input is needed. It may be related to U.S. patents 2183248 & 3012098 assigned to Bell Labs?
KY-65 controls: & Indicators
INT BAT / AUDIO / EXT BAT
OFF / ZEROIZE / STANDBY / ON - standby uses the external DC power for keep alive, saving the HUB batteries.
PLAIN / CIPHER
DELAY OUT / DELAY IN / SIG CLEAR
HF / NON HF
Uses two each BA-4386 batteries.
The KY-99 Miniterm replaces the KY-65 for voice security.
NESA N00140-92-C-AB15, RT-1209 to KY-99, 29357-46923-202014-24
The RT-1209 end goes to an AUDIO connector on the RT and has a 5 contact U-229 type connector, except it looks to be TEMPEST rated. KY-99 end that attaches to the RADIO connector is a MS27467T11B35S. This is a 13 Socket connector. This cable has a 1992 contract date, so the KY-99 was supported at least this early.
[an error occurred while processing this directive] page created 28 Nov 2003.