I am restoring the above receiver and transmitter for a friend here in Costa Rica. The receiver didn't give much problems, but the transmitter was "worked on" before. I think that there wasn't a single trimmer cap or slug that wasn't touched and mis-aligned. The balanced mixer had other diodes and I couldn't null the carrier enough. There were various caps non original and some short circuited. A few high resistor values way off. etc, all quite common and simple to solve problems. What gave me a bigger headache was the the coil of the antenna relay was broke. I think it is a 100 V relay from Potter and Brumfield, and I wasn't able to find one. The wire is approx. 0,05 mm, so rewinding without a machine is close to impossible. I tried but the wire broke 4 times and I gave up. So I did rewind the coil with 0,15 mm and that gave me a relay that operates at approx 6,5 Volts. Rectified the 6.3 VAC filament voltage and powered the relay with that instead of 265VDC via two 8.2 kOm resistors as original. Its a small mod, but the transmitter works again. May be a tip for high voltage relays that can't be found.
The power supply transformer has a short and pulls the fuse. Even at 12VAC instead of 115 it takes a few amps unloaded, so I have to try to find one or replace the transformer with a Hammond type that come close.
When ready I will miss the S-line, it was real fun to get them going again
Fortunately, the owner had a spare set on acceptable condition without power supply for spares, and he gave them to me for the repair. So I can do it again. But this time they will stay.
Nice stuff.