Radio Control Panel

Control Sun-Assembly
640/1/22400/124
Serial No. 10109
Plessey Avionics
────────────────
Board Position
Converter Digital (Display) 419/1/25115
Store Digital 419/1/85039
Multiplexer 419/1/25492/100
Converter Digital (Mode) 419/1/25479
Power Supply 419/1/85045
────────────────
[ink markings]
MA046614
STI/586
[B]ACK
STF/TOR/427
5821-99-352-6869 [NSN]

This Radio Control Unit is very similar, perhaps an early version of the Manual and Preset controller option from the ESD1741 lightweight VHF military airborne transceiver. This system is designed to provide high-reliability air-to-air and air-to-ground communications in all types of helicopter and fixed wing aircraft and is intended primarily for air traffic control use.
The equipment consists of two units, the transceiver and the control unit. Two alternative control units are available which either provide manual selection only of frequency or this one which has manual selection of frequency plus 30 preset channels. Both control units incorporate a built-in test equipment facility to check output power, modulation depth, and receiver sensitivity. A non-volatile store is used to provide the preset channel memory.
The unit is designed such that it can control two transceivers, one VHF and the other UHF.
Power for the transmitter and control unit is taken from the aircraft +28VDC supply.
The radio products of Plessey were taken over by GEC-Marconi at both the Basildon and Christchurch sites. This may be a GEC-Marconi manufactured item although Plessey would have been the designers.
The Panel was fitted to the Saudi Tornados