Built during 1956 – 1962 the Eddystone 730/4 is a professional commercial receiver based on the 680X  with 15 valves, 2 RF stages, 2 IF stages (450kc/s), BFO, IF cathode follower output, variable IF selectivity, xtal filter, xtal calibrator, adjustable scale, noise limiter, S-meter, audio filter for CW, fully tropicalised. Cost at time of manufacture £230. This receiver was ordered by the Ministry of Defense in large quantities and used by the Royal Signals The opportunity arose for me to purchase an Eddystone 730/4 spares or repair from the family of a Silent Key at a reasonable price, so I … Continue reading →