With the series resistance of 100k you loose 200V and get 450-200=250V on C24.
If there is no 450V simply adjust the resistance to get the voltage right again.
No precision needed, 10V more or less isn't important.
Mona
If there is no 450V simply adjust the resistance to get the voltage right again.
No precision needed, 10V more or less isn't important.
Mona
After driving back this morning, I started to tinker about with the amps. On the power amp, I changed octal plug pin 3 to the tie point in between C13 and R15. This is now supplying the preamp with 410V. (All voltages in the amp are a little low, even after changing rectifiers)
After C24 in the preamp, the supply voltage is at 250V and the plate voltage of the ECC40 is 75V. It's extremely cramped inside the chassis and fairly impossible to get to either cathode to measure that voltage. I hooked up the record player and was able to play some 45s through it. I'll have to fool around with the various inputs as well.
My next step is going to be swapping R5 out from 120K to 150K. Then I'll go ahead and see how adding the original 100K gain pot affects things.
After C24 in the preamp, the supply voltage is at 250V and the plate voltage of the ECC40 is 75V. It's extremely cramped inside the chassis and fairly impossible to get to either cathode to measure that voltage. I hooked up the record player and was able to play some 45s through it. I'll have to fool around with the various inputs as well.
My next step is going to be swapping R5 out from 120K to 150K. Then I'll go ahead and see how adding the original 100K gain pot affects things.
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