USSR/Czech VHF transceiver A7b

VHF man pack transceiver A7b

Czech type A7b VHF man pack transceiver was a post-war version of the USSR A7a set. (Go to the War time USSR A7a   for more details on the USSR parent versions of this set). Both Czech and USSR versions are mechanical and electrically very similar, differing only in the frequency range and use of more contemporary components such as resistors and condensers. The A7 series are man pack sets, though looking at the shape of the set, its heavy weight (50lbs) and unsuitable carrying harness it must have been an awkward load.

• Frequency range 24-28 MHz. RF output approximately 350-450mW.
• Frequency modulation is employed, deviation is not known.
• Production date is estimated in the early 1950s.
• Mechanically the A7b comprise a transceiver unit in a metal box, sliding in the top compartment of the wooden carrying case.
• Fitted in the bottom of the carrying case are a pair of 1.2V Nicads to provide 2.4V LT and 120V dry batteries for HT.
• Antenna sections, long wire antenna and counterpoise, along with micro telephone, Morse key and headphones are stowed into the centre compartment accessible via hinged lid.

Transceiver unit A7b

Front panel layout of Czech A7b transceiver unit. The tuning dial is calibrated in 50kHz divisions. The receiver section has a fine tuning dial (bottom centre). An interesting detail is that the set can be used as an ordinary field telephone, having the two line terminals 'L' and Ground. The function switch on the top left hand corner has three positions: Calibrate, Telephone and Radio. The meter is calibrated in volts. The voltage to the filaments is adjustable by the control just above the micro telephone socket. The 120V HT is read by simultaneously pressing the handset and the small button on the meter.

War time USSR A7a