RACAL TRA-967/3 VHF FM Transceiver

Updated 7/3/23

This is a RACAL TRA-967/3 VHF FM transceiver that was formerly operated by Saddam Hussein’s army in Kuwait during the 1990-1991 Gulf War. AKA Operations Desert Shield, Desert Storm, Granby (UK). The faded paint markings on the carrying bag are translated from Arabic as “9 F 17”, possibly a unit designation.

The following is a brief description of the radio and my observations on its design, capabilities and operation. These sets were made in England; this one sports component date codes including week 40 of 1978. It is well designed, functional and very capable. I like it.

Some basic specifications from the manual:

• Frequency coverage: 36.000-75.975 mc
• Channelized in 1600 channels spaced 25 kc apart
• Power Output 3 watts (/3 version), 1 watt (/1 version). NBFM, 5 kc transmit deviation. Planning range approximately 8 km.
• Power supply is 12 volts nominal from NiCds or 10 C Cells in clip-on battery boxes or an external vehicular supply. RX=50/120 ma (standby/receiving), TX = 1.4A (3 watt version)
• Battery life (3W) is approximately 11 hours, 8:1:1 (Standby: Receive: Transmit)
• Operating modes include: ON – (RX carrier squelch*), Whisper mode (20 db mic boost), Rebro (relay) mode (with 2 connected transceivers). It also has 150 cps T/R tone squelch in Rebro mode plus a Noise (squelch disable) function.
• * The 150 cps “pilot” tone is transmitted in every mode.
• Frequency display illumination is via tritium/phosphor lights, now long dark.
• Antenna options include a collapsible 7-piece, 1.2 meter whip with flex gooseneck and a BNC connector for an external 50 Ω antenna or RF amplifier.

Some Context: According to a former RACAL employee these sets were developed primarily for the export market to foreign governments, militaries and paramilitary groups. It is a capable although less expensive alternative to more “ruggedized” equipment such as the contemporary Clansman series. These apparently sold quite well, I can see why.

Saddam bought a lot of RACAL equipment like the TRA-967, including its “sister” HF radio, the TRA-931 seen here inside a captured Iraqi/Russian BMP-1. (Authors photos)

However this BMP Command vehicle did not include the TRA-967 for VHF FM; it used the more powerful 1960’s Russian “Magnolia” vehicular set instead as seen below. They have limited but useful interoperability. Maybe Saddam’s embarked conscripts carried a TRA-967? Below is the R-123M Магнолия inside that aft, right hand door.

(This armored vehicle fared much better than Putin’s BMP’s in today’s Ukraine….) But I digress.

An obvious TRA-967 comparison could be made with the US AN/PRC-25 or the AN/PRC-77 VHF FM manpack sets; those designs from about 10+ years earlier. The PRC-25 (below) even included a vacuum tube PA stage; the PRC-77 quickly updated that design with a transistor. The TRA-967 is all solid state.

They have very similar capabilities and intended usage. They are interoperable where their frequency coverage/selection overlap. The narrower transmit deviation and IF bandwidth of the TRA-967 versus the PRC-25/77 enables the 25 kc channel spacing but they are still interoperable with adequate audio recovery.

The lowest operating frequency the TRA-967 provides is 36 mc versus the 30 mc of the PRC-25/77. However its 25 kc channel spacing gives the TRA-967 1600 channels versus only 920 for the PRC-25/77 with their 50 kc channel spacing, despite its wider frequency coverage.

The TRA-967/3 3 watt output is about 1 db more than the PRC-25 and it is also smaller. It is less than half the weight of the PRC-25 but maybe somewhat less rugged as a result.

This one receives great with good sensitivity and fidelity on the local Highway Patrol and other low band VHF Public Safety channels as well as transmit/receive on the 6 meter Ham band.

I did have to replace the handset coil-cord as it was shot. I don’t know what the significance of the handsets green and red earpiece/mic denote. (Stop Talking – Listen!)? Always good OPSEC or even personal advice. Anyone?

I even like the radio’s color – British Racing Green ?

Both sets provide infantry squad/platoon/company units with short range, reliable tactical comms up to about 8 km depending upon terrain. Both sets can be integrated with vehicle mounts, antennas, crew intercoms, vehicle power supplies as well as their attached battery packs.

The TA970H 25 watt RF Amplifier was available for vehicular/base station service; that mounts in a special rack with the transceiver.

Below is the handy MA 968B battery box for 10 easily obtainable “C” cells. Simplifies logistics support downrange. The MA-968A NiCd box is similar but they are rechargeable.

Note: I have stopped using Duracell batteries in my equipment whenever possible. Some years ago they changed the design or manufacturing process and now I find that too many of them will eventually “leak”. The alkaline chemistry uses corrosive potassium hydroxide which then forms potassium carbonate, that white powder seen leaking. Some cells even leak in original packaging WELL before their “best by” date. Certainly, DON’T leave them in standby equipment. Beware, YMMV.

Above: The black “screw” in the lower left hand corner is a 20×5 mm, 2.5 Amp fuse.

Although well sealed, it takes a screwdriver or a penny and a bit of time to open up the box to change the cells and then reassemble. But it works, I like it.

The radio’s design includes good environmental protection with a gasketed 1-piece aluminum case. It comes with a nylon canvas shoulder bag with extra pouches for the whip antenna and handset. There are provisions for 2 audio devices such as a handset and speaker.

Repairability access to the 2 PC boards is good. Many test points are available although I find that fault-finding is difficult due to parts density and limited published component location and PCB layout wiring drawings.

The late 1970’s technology includes many low power CMOS devices and some ECL logic in the PLL circuit. It has a clever 5-voltage power supply regulation system and an equally clever “battery saver” system to reduce power consumption while standby/receiving.

A known weak spot with these radios is the tantalum capacitors that are used extensively. They have a high failure rate after 45+ years; there is some bad electro-chemistry Booga Booga going on inside them these days. I am sure they were fine during their expected service life.

I have had to replace 5 caps plus a shorted relay coil snubber diode (which does not appear in the schematic!) in this example but the set is otherwise reliable. Below are the 2 main (RF and Synthesizer/power supply) circuit boards:

Most of the tantalum capacitors have either a blue or red epoxy body; the resistors are held in place vertically with the little red and green plastic vibration mounts. Note the absence of MFP, solder mask and limited use of silk screening of component labels due to the dense layout. The set has very tight packaging from before the time when ASIC’s or LSI circuitry became commonly available. It’s a very good design for the times.

These sets have a reasonable presence on the Interwebs for additional information and peripherals descriptions. Not much out there regarding development or sales/deployment. RacalRadio@groups.io is a good source for current information on Racal equipment. For further circuit details see Ray Robinson’s excellent tuberadio.com website on the TRA-967, Reference 109.

Some field ops and interoperability evaluations were held at the recent west coast Military Radio Collectors Group event. We operated over a few hundred meters radius on 51.00 mc. That frequency is commonly used by US and other Hams operating military gear.

We had the TRA-967, PRC-6, PRC-10, a Czech RF-10 and a ricebox on the net. They worked together very well within their individual deviation specs.

The TRA-967 can tune 52.525 mc for work on the US 6 meters simplex calling frequency, something the PRC-25 https://www.n6cc.com/prc-25-radio/ can’t do due to its 50 kc channel spacing. Both radios can also work on the 4 meter Ham band in Europe and elsewhere where authorized. Also note that neither of these sets can provide a transmitter “offset” to work with Ham repeaters. No worries, simplex works.

Below is my 2023 Field Day portable setup in the woods. The TRA-967 was along for 6 meters activity. However I was located in a deep canyon using HF NVIS to work CW and SSB on 40 meters: No 6 meter signals were expected into this location. But the radio did monitor the local Highway Patrol and local parks police and fire department repeaters (situational awareness).

Stay tuned for reports on future field ops.

AR

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