Produced

1939 - 1945

Standard frequency range

6 - 9 MHz

Transmitter RF output 

0.25 Watt

The Wireless Set No. 18 was the first mass produced set for the British Infantry and was specifically known as a man pack.  It was based on a design by the Government Signals Experimental Establishment (SEE) however; Pye Limited took a vested interest in it's development and was approached by the Government to enhance it's capabilities.  It's rapid development and production was due to the emense loss of wireless equipment at Dunkirk in 1940.

Designed to be carried by one man and operated by another (although this was not pre-requisite).  The WS18 primarily consisted of two parts.  The tuneable transmitter and receiver units mounted in a back-pack style carrying case, with integral battery mounted in the base of the case.  A sectional vertical rod aerial was used mounted on a base at the side of the case with the aerial sections being housed in rack on either side of the casing.  In addition to this.  There was a 25 yard ground aerial wire which could be plugged into the aerial base and either run along the ground or suspended from a branch or building.  This made the operator and wireless station less conspicuous.  A traight was to glue the ground aerial board to the top of the wireless casing.  This appears to have been unique to the British Airborne.  The above set, from Arnhem, has evidence of this still in place.  

The  2 Volt filament type valves were extremely fragile and were often damaged during parchute drops somewhat limiting the operational use of the equipment as happened during Operation Market Garden.

The first sets came off the production line in 1940 and were extensively used in North Africa, Italy, South East Asia, Normandy, Arnhem and during the Rhine Crossing.  More than 76,000 sets were made by Pye and a number of other sub-contractors.

During 1943 the monthly production average was around 2310 sets.