Hi All,
The receiver referred to by Hawker is the Royal Navy Outfit CJA/CJC.
More info at:
http://www.commsmuseum.co.uk/receive...%20CJA/cja.htm
The receiver in the attached photo belongs to Don ZL4GX and shows the receiver with its associated Frequency Synthesiser.
Outfit CJC was a single receiver in a desktop cabinet without a synthesiser. Outfit CJA was a dual receiver installation with each receiver having an associated synthesiser in a floor mount cabinet and weighing nearly half a ton! The receiver alone weighs more than 150lbs. and is the only receiver I know which need air cooling - the cabinets have forced air circulation and there is an air intake port on the receiver to duct air to the IF amplifiers.
The synthesiser is not a true synthesiser in the modern sense. It compares a sample of the receiver local oscillator with an internally generated signal derived from an external 100kHz source to derive an error voltage. This is the fed back to the receiver to a reactance modulator on the local oscillator to correct any frequency error.
The Outfit CJA was intended primarily for the un-attended reception of RTTY broadcasdt traffic, and replaced Outfit CJK (Racal RA117E etc.) which had been introduced as a stop-gap due to the late delivery of CJA.
The extreme front end performance referenced by Hawker is achieved using selected ECC82 cascode RF amplifiers and 6 tuned circuits at signal frequency, housed in a massive turret.
Few of these receivers (and none of the synthesisers) seem to have survived in the UK, possibly because of the silver-plated chassis making the valuable as scrap.
If anybody has a synthesiser they don't want please let me know!