Have a ST70 bias issue and questions.
Left channel will only reach 1.3 VDC and bias pot is maxed out. Center tap of bias pot to ground is 9.8K ohms.
Right channel is good at 1.56 and pot is not maxed out. Center tap of bias pot to ground is 12.1K ohms.
Components in the bias checked good.
Swapped the left and right channel tube pairs. The problem followed the tubes to the right channel, left channel bias ok to 1.56 VDC
So now the problem is in the right channel. Tried a completely different pair of tubes in the right channel and maxing out around 1.33 VDC.
I did notice that the 2 x .02 disc cap is bubbling but did not measure any shorts there. Would this effect the bias adjustments?
I will attempt to include two images in this post.
Thank you. MC
ps. I also noticed a lot of wax on the bottom cover that must have dripped from the choke. Is this something to be concerned about?