if one or more caps are blown (i.e. show as open circuit to AC), then your meter may be showing something closer to the peak (unfiltered) voltage.Hi, I wonder what could cause too high voltage from filter caps? Might be a difficult question, but if there are some general rules?
That’s still only the layout you posted.That's interesting Vanyu, why do you think that? I mostly used that layout yes? But I have the schematics as well:
Now that we have a schematic, it's very easy to devise a troubleshooting strategy!... I seem to get a bit high voltage, about a 100 more voltage on b5 and b4 than the schematics states. It seems like the tubes doesn't get any working feed, there is only a very low hum in the speaker. ...
Check the screen grid resistors they may be openSorry about the vague kind of question. I am building a Dumble clone, and when I finished it there was sound going through, although not the right sound. Then at some point it all went dead. I have changed all the tubes and they seem to be OK, glowing as usual. Normally you can get some "scratch" sounds when you touch certain pins on the tubes, but nothing. When I measure the B+'s I seem to get a bit high voltage, about a 100 more voltage on b5 and b4 than the schematics states. It seems like the tubes doesn't get any working feed, there is only a very low hum in the speaker. This amp is difficult, bit too much I must admit.