I took my time and the summer to build it. I had a couple of errors along the way , like the back on the front and attenuators upside down . Lol . Ordered more wire , tore it apart and made it right. But I had a hum I could not find and finally threw in the towel and sent the board back to Roy . I had two sets of resistors mixed up as I had either marked them wrong or measured them wrong with the meter. It was , I think 280 Ohms verses 280 k ohms ? Anyway Roy changed them , tested the board and sent it back.
But the problem still persists . Rotating the volume attenautor from low to high ........ There is distinct hum at the low end , this lessens or disappears by mid point. At the extreme end of the dial ( or max ) the hum will re-appear. This is with no input running of course . Plays music sounds ok at mid volume. But to me I don't get as much volume as I would like either ?
I used a SS preamp prior too and it had plenty of room . System is in the basement and I crank it sometimes when we are upstairs.
I had to unsolder and turn the attenuators around , so not sure if they could be over heated them and cause me problems. That will be my next step. Order a new one and run directly to it from one of the jacks.
This what I have done so far:
All voltages check out as per Roy's instructions. I have tried new tubes. I have wired directly from one set of jacks to the attenuators , thus bypassing 90 percent of the wiring and switches with in . I ran a ground from the board to the ground buss to try that and nothing changes.
We will assume the board is fine as Roy tested it . Either I have missed something or a transformer? Not sure how you could check that as I don't have an oscilloscope .
And yes I probably should have just sent the whole thing back , but I was sure it was the board and cheaper to send it as I live in Canada.
I see Roy is away. So any help would be much appreciated.