The GRC-215 radio was a complete radio system that was designed to be mounted in a Military Chevrolet Blazer.  This was part of a military radio system refereed to as the Regency Net.  The Regency Net was designed in the 80’s to be a HF radio net for the US Army to be used for tactical communications in a nuclear environment.  The GRC-215 system had the capability of removing the R/T (receiver/transmitter) unit from the Blazer package and using it as a portable HF radio.  The components needed to operate the portable radio were obtained by FEMA from the military to be used with US&R Task Forces.  The components are in new condition and have never been used.

The original GRC-215 had crypto and frequency hopping capability.  These components are restricted items and not supplied to FEMA as part of the backpack system.  These components were removed at the Army Depot prior to being shipped to FEMA.  Some of the removals were not done in a first class manner and you should inspect the radio prior to use.  All of the mounting screws on the face of the radio should be tight and snug.  There should be no loose parts.  If the face screws are loose or if you hear loose parts in the radio, undo the front hex screws and pull the chassis out of the case.  Make sure all of the boards are seated in the chassis.  Replace the chassis in the case and tighten the front screws.  With a small screwdriver remove the front plate that says “Contains KGV-10 TSEC” and discard as the unit does not have a TSEC unit in it.

The unit runs on the enclosed NICAD batteries.  You will have to make a charging kit and there is an explanation about this circuit attached.  Read this explanation carefully as most of the initial problems have been with battery charging.  Although the batteries have aged some, we have only found one bad battery to date.  You may also use BB-590/U Lithium batteries (obtainable though DLA, DRMO, or local military units with this radio.  The charger can also run the radio.

The most important part of the performance of the radio is the antenna.  There are several web articles attached about NVIS antennas:  http://www.qsl.net/vcars/CARL/NVIS.html and http://www.gordon.army.mil/acd/tcs/hf/2418xtr2.htm   A properly tuned NVIS antenna gives 95% coverage out to several hundred miles.  As you will see in the literature the unit must also be operated below the “MUF” (Maximum Usable Frequency) for reliable coverage.  A note on the antenna connectors.  The BNC connector has an output impedance of 50 ohms and can feed any 50 ohms antenna.  When the whip antenna is inserted in the connector for the whip, the protrusion on the whip connector activates a switch in the connector and changes the RF out as well as forces the radio to tune the whip.  Technicians on the MATF-1
TF have removed the adapter from the bottom of the whip and connected a wire to it and used it to feed antennas that are not 50 ohms.

When you turn on the radio it will go through a series of internal tests, including tuning the antenna.  Should the radio see an unacceptable match it will go into the fail mode.  Depending on whether it is a soft or hard failure, the radio may inhibit the transmitter.  You can then change the antenna and force the radio to reset (see operating instructions).

The handset supplied with the GRC-215 is not a standard military handset (even though it looks like one).  It has a special microphone circuit and if you use a standard handset you will get extremely low audio.

These instructions as well as some other useful documents are posted at the web site: http://www.matf.org/grc215.htm

If you have any questions or comments you can send them to: mfoster@shore.net

I would appreciate you sending me comments as I can pass the information along to other TF’s that are fielding these units.

Mark Foster, TFL – MATF-01

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