The first photo here shows the faulty set. The relay ive been testing is located in the bottom right corner of the PCB, which is unit 6. In this state, with unit 2 (the rear section) attached, the radio operates, and I can check at least a few voltages.
Above is the test-bed radio with unit 6 in the 'service' position. How your meant to service the radio like this when the back doesnt attach the manuals dont say. The relay can just be seen behind the pink wires at the bottom. There are three components associated with this relay, a 100 ohm resistor, a 68nF capacitor, and a 180uF 6.8v tantalum capacitor. All are suspect! The tantalum isnt part of the relay switching like the other two, but is a smoothing capacitor on the 6v Rx rail. If I have a suitable part then this might get replaced anyway! The various audio module cans are shown here, of particular suspicion is the top one, 6b, as this has another big tantalum in its 6v Rx rail!
From the other side. The other slave relay is part of the turret tuning mechanism, which is the big metal block in the middle! You can just about see the relay in the middle of the side plate, part hidden by the tuner unit.
And the view from the other side, which shows just how difficult it will be to work on the relay in the turret tuner!
So, my plan is thus - tack solder an LED to the 6v Rx rail and see if I can discern any link between the delay in return to Rx and the switching of this rail. If so, or if inconclusive, I will replace the associated components, and if the fault remains, will exchange the relay.
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