I seem to have lost my bias adjustment capability on my AC-3. When tuning up the TR-4C I get normal output but am unable to dip the plate current...that is it peaks about midrange and minimizes at both ends of the meter spectrum. I only tested this on 40 and 20. That's when I noticed that I can't get the bias to adjust. I've checked for proper PS output voltages and for any unwanted AC on those outputs, but it all appears normal. Suggestions?
