03-16-2012, 03:02 AM
(03-16-2012, 12:17 AM)TA Forbes Wrote: Is the grid cap on the tube loose? I am talking about the silver cap that should be premanently affixed to the top of the tube, not the wire connector end. If yes, that could be the issue.
Try replacing the 75 with a strong tube and go from there. The 75 is the first audio/2d detector tube, and the volume control feeds the grid of the 75 through a .01mFd cap.
It could also be a flakey solder joint on the lead near the clip, or the wire breaking internally near the clip, those are pretty common problems around a grid cap along with the cap itself.
Regards
Arran