Description taken from Wikipedia
An HF/USB/AM/CW transceiver built by Plessey and issued down to company level. The set operates in the 2-29.9999 MHz range with a possible 280,000 channels. RF power output is a selectable 3 or 30 watts. Derived from an earlier prototype known as the B20, the PRC 320 can be used as a manpack (backpack) or vehicular radio and it originally replaced the Larkspur Station Radio (SR) A13 SR C13 and other HF Radios in service with the British Army.
The PRC320 can be used with a number of different Clansman antennas that are supplied with the set; A 2.4m whip antenna is supplied for portable manpack operation using HF groundwave communication. Alternatively a dipole antenna can be used for HF Skywave operation. The set includes a built-in Antenna Tuning Unit (ATU), this electrically matches the whip antenna length to the radio frequency in use. The ATU can also match any other wire antenna to the operating frequency. The set together with its ancillaries (batteries, cables, audio gear and antenna parts) together make up the complete equipment schedule (CES).
It is a well known fact in signalling (military radio operating) that the use of morse code and later data transmission and reception could extend the range and add to the versatility of the UK/PRC 320. After Market a number of data entry devices were produced as add ons such as MEROD, TDED and Kipling.
Current Users. Clansman HF Sets are still in use in the UK by the Cadet Forces. Many of the sets have found their way into amateur service since the Clansman system became obsolete.
This is a picture of a 320 on its para-frame along with its accessories. This is shown with the hand charger and 1Ah battery. My own one is fitted with a 4Ah battery and I don't have the hand generator for it. I do have all the other accessories for it though along with several pressel switches and the alternative telephone style headset.