Post by mb9513 on Jul 23, 2017 0:21:31 GMT
Hi all, I am trying to get a 514 amp working properly. this is the most difficult amp I have ever had the misfortune to work on. it had low volume. after a recap, same problem. I started going through the resistors that bring the signal to ground. that helped somewhat still only moderate volume at full tilt.
then I just lost all sound, totally. have checked the connections for cold solder(again). retested the tubes, all good. then went to inject signal into the tube grids and got sound all the way back to the oscillator.
I do not know how to test that section of the amp. I tried injecting signal into the screen grid of the 6J5. nothing
other things I have done is disconnect the mute plug so the amp is live all the time. have checked the line to the cartridges, there is continuity. the A-B micro switch was replaced earlier in the repair.
this amp is the very last issue I have with this 1400. please help! if I had hair I would be pulling it out now. Thanks Mark
