Drake 2C troubleshooting

[iw5ci]

I am trying to fix by myself.
Syntoms:
slight hum on speaker and maximum volume very low
vfo is working i can tune stations over the bands but the reception is just above noise
no meter deflection , the preselector peaks on the correct segment but signal are extremely low, only the strogest may be audible.
ssb is ok because if i ear a station the sound is good, selectivity control works.

AGC is not working as in off slow or fast position there is no difference.

RF gain working as when i deduce it the s-meter goes up.

I have swapped all the tuber with other tubes got from a good working radio, so tubes are ok.

Any suggestion about where to start?

[WQ9E]

Check the voltage from the power supply (at C46, C47, and C48); this will give you a quick check of the power supply, the main filter caps and their associated dropping resistors. 

If these are normal then I would suggest either checking voltages at the tube sockets or using signal injection stage by stage to check for gain/faults.  Checking voltages will probably be easier in this case.  If those are normal then it is time for a signal injection test because you may have a problem in an IF transformer.