The T.3180 ‘Walter MK.1’ transmitter, stores reference 10DB/975 was a compact portable homing transmitter designed to help locate downed airmen. It was fitted with a telescopic aerial mast and integral dry-cell battery power supply that emitted a pulsed signal that could be received over a range of up to 20 nautical miles by airborne ASV Mk. II radar sets or Rebecca Mk.IIb equipment fitted in Coastal Command and Fleet Air Arm aircraft. In use, the telescopic mast extended to a height of approximately 6 ft. with the oscillator unit and wire dipoles at the top linked to the switch unit and battery case with thin wire leads. The mast was fitted with three guy ropes that secured it to the dinghy sides. The lower section of the unit was held between the airman’s knees with a felt pad fitted to the base in order to prevent slipping and damage to the dinghy floor. To preserve the battery it was recommended that the transmitter be operated for 15 minutes at a time at five-minute intervals and only intermittently until an aircraft or rescue craft was sighted. The 'Walter' was used in single seater dinghies, type K, the sailing dinghy type Q, in multi-seater dinghies types L, M, M1A, H Mk.III and K Mk.III, and also in airborne lifeboats, Mk.I (Hudsons) or Mk.1A and II (Warwicks). Superficially this looks excellent but the mast is stuck in the 'stowed' position and I don't want to force it. There are no obvious problems with the tube so am guessing that with some care and effort it may be possible to extend and erect the mast. The battery case is complete and has the felt base pad and all three guy ropes/clips are present. The oscillator unit case and switch unit both appear to be excellent and the dipoles are in place. These are rare and sought after. A great display piece or use to complete your dinghy pack. Stock code S24323.