Special radio receiver `` PR-56 ''.
Receiving and transmitting radio equipment.The special radio receiver "PR-56" has been produced since 1956. A special short-wave transmitting and receiving portable telegraph radio station `` Rion '' is designed for simplex and half-duplex two-way communication. The radio station operates in a smooth frequency range from 2.5 to 10 MHz (transmitter) and from 2 to 12 MHz (receiver `` PR-56 ''). The radio receiver of the radio station allows operation in the self-excitation mode of the master oscillator or with quartz stabilization (quartz crystals can be used at the fundamental and second harmonics) in the entire frequency range. The switching scheme of the radio station allows simplex operation using one antenna, as well as half-duplex operation; in this case, an additional antenna must be deployed for the radio receiver. The sensitivity of the receiver in the telegraph mode is 5.5 µV. Transmitter power 5 ... 10 W. Subsequently, apparently there was a modernization of the radio station, since the radio receiver added the index "A" to the name "PR-56". There is no exact information on this yet.
