Relay problem solved. I learned a few things about AC powered relays. You can't bring them up on a variac slowly or they will chatter between 50 and 100 volts. They need to be operated at their full voltage, over 110 volts. It turns out that when using the dim bulb in line with the variac, the voltage drop was too much, and the relay dropped below its cutoff voltage and started to chatter. With 115 volts AC across the contacts, you get to see some sparks (not good). I turned off the dim bulb, set the variac at 120 volts and flipped the switch! The transmitter powered up and started drawing about 1.2 amps. No smoke or explosions :)
Did some more work on the Navy TCS receiver. I finally located the missing resistor. They were really tricky and added it to the back of the RF gain pot. I then checked the resistances. Now the pin that is supposed to read 1M reads 1.3M. So a little high, but within the ballpark. Next I ran a signal of several hundred micro volts directly into the antenna. No signal was heard. That probably means that the oscillator is not running. Time to read the manual again :(
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