[Ron Ramirez]

At the workbench.

I think the main problem was the balance control.

Just now, I fired it up again and after a few coughs and sputters, the left channel came to life. Wiggling/tapping components around V20 had no efect.

Then I twisted the balance control.

The left channel went away, only to return a short time later.

A-HA! The balance control is made in such a fashion that the rear portion of the control (the left channel) has the terminals at the bottom of the chassis, so it cannot be reached with DeoxIT or any other spray chemical unless one (a) disconnects and removes the control in order to clean both sections; or (b) gets the rear cover just open enough to get some chemicals inside.

I had forgotten that I cleaned every control except that section of the balance control.

I went with option B. Carefully, I managed to get the rear cover open just enough to give that section a brief blast of DeoxIT, followed a short time later by FaderLube.

I tried it again - and the right channel came up, followed by the left channel a few seconds later. I'm hoping that is because I'm testing the unit with its original (and extremely weak) Fisher-branded 7189 tubes.

I twisted the balance control left and right, and there was no snap, crackle, or pop.

I can live with a few seconds' delay from right channel to both. Although, this unit wasn't doing that before my latest round of replacing coupling caps and making the low-high filter mods.

I think I will move on to the IBAM board now.