kingfredward
Well-Known Member
- Joined
- Sep 30, 2022
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Sorry I should have clarified. that was without tubes. Shall I try with tubes? I can garantuee ill have the same resultThe tubes are not conducting because if they were, your ht would be lower. I cant see from the pics but is there a lead going to ground from pin1 of the power tubes?
Good advice. I have continuity between both pin 3s and I have a solid connection. Any other suggestions?Turn amp off, drain filter caps and with dmm on continuity test, check between this junction and pin3 of power tubes. Report back readings
View attachment 158974
Yes, 162 negative volts is not right. The max is usually in the -70V range. That will stop the tubes from conducting. What are the readings from pin3 to center tap for both tubes?Good advice. I have continuity between both pin 3s and I have a solid connection. Any other suggestions?
Great I’ll try that. Could you point me how to measure that reading? Not entirely sure what the centre tap is. Sorry still a complete noobYes, 162 negative volts is not right. The max is usually in the -70V range. That will stop the tubes from conducting. What are the readings from pin3 to center tap for both tubes?
Its on post #167. You want the readings in ohm. Write them down for both power tubes and report back.thanks for your continued help and patience
Also noticed I never need to discharge this cap
View attachment 158987
Great I’ll try that. Could you point me how to measure that reading? Not entirely sure what the centre tap is. Sorry still a complete noob
Take the readings i asked you. And clean between those turrets, there are a lot of small solder balls in thereI think I found the issue!!!
Cold solder and loose connection could that be plagueing the whole system?
View attachment 158988
I think I found the issue!!!
Cold solder and loose connection could that be plagueing the whole system?
View attachment 158988
thanks for your continued help and patience
Also noticed I never need to discharge this cap
View attachment 158987
Great I’ll try that. Could you point me how to measure that reading? Not entirely sure what the centre tap is. Sorry still a complete noob
Ok, its not clear from the picture, but is the center lug of the trimpot connected any of the other two lugs of the trimpot? If not, connect it to the lug thats connected to ground. Do that and measure again the max negative voltage at either pin5 of the power tubesHere’s the View attachment 158989View attachment 158990trim pot I have cleaned all the Debry off it too (not seen in the photo)
Anyone got any suggestions what to look at next?