Posted by Kevin on January 30, 2003 at 17:32:38:
In Reply to: Re: Comment from Duke? posted by Mike Bieda on January 30, 2003 at 15:14:28:
>Found that a very, slight/imperceptible move of the screw made a significant difference in balance.
I had this problem too once and after some investigation I discovered that the bias pot had developed a "dead spot". This was when I had the bias control almost fully clockwise so perhaps the low series resistance allowed a large current to flow, presumably during a line surge, that burned out the resistive element in one spot. As mentioned elsewhere, I now turn the bias control all the way down when I'm not listening, and one benefit is that the large 10K series resistance limits any current surge to a few tens of milliamps.