My Guess is that the missing resistor is quite low in value as it's in a high current low voltage situation, as has been said some details about the resistor might help, as was explained earlier it might be possible to work out with a reasonable amount accuracy what its value was.
From the PSU schematic you posted it looks like the AC supply to the rectifier that supplies the PA supply is 40 volts? and that the AC input to the other rectifier is 7 volts?
If that is the case then I would say that the 40 Volts is for the PA and the 7 volts is for the preamp and processing.
In the absence of a current limiting variable bench PSU I would start with the amplifiers PSU and get that up and running under a load in isolation from the rest of the amplifier, if you know what the continuously rated RMS output of the PA is you can get a rough idea of the PA's current draw as you can roughly work out approximately what the B+ supply is by calculating it from the AC RMS input to the PSU.
From all that you can work out the value of a suitable dummy load to connect to the PSU, I would work out a value that is suitable to simulate the PA's current draw at half it's rated continuous RMS output and would run it like that for an hour to make sure the transformer etc is ok.
Lawrence. EDIT: Whoops...missed refugees post.
From the PSU schematic you posted it looks like the AC supply to the rectifier that supplies the PA supply is 40 volts? and that the AC input to the other rectifier is 7 volts?
If that is the case then I would say that the 40 Volts is for the PA and the 7 volts is for the preamp and processing.
In the absence of a current limiting variable bench PSU I would start with the amplifiers PSU and get that up and running under a load in isolation from the rest of the amplifier, if you know what the continuously rated RMS output of the PA is you can get a rough idea of the PA's current draw as you can roughly work out approximately what the B+ supply is by calculating it from the AC RMS input to the PSU.
From all that you can work out the value of a suitable dummy load to connect to the PSU, I would work out a value that is suitable to simulate the PA's current draw at half it's rated continuous RMS output and would run it like that for an hour to make sure the transformer etc is ok.
Lawrence. EDIT: Whoops...missed refugees post.
