03-07-2016, 06:14 PM
Did you replace the 40-40-40 filter that filters the E supply? If you did, E is probably OK.
From the symptoms in your original post, I suspect the input jacks are not shorting the input when no plugs are inserted. Did you move any of the grounds from the main filters that might not be rewired correctly? I've had many Ampeg hum pots that are intermittent, especially if there was ever a shorted output tube. You may have a bad hum pot. With the amp off, measure from ground to each side of the pot while turning the shaft. Each side should go to ground. I usually change the hum pot it is not 100 percent solid.
From the symptoms in your original post, I suspect the input jacks are not shorting the input when no plugs are inserted. Did you move any of the grounds from the main filters that might not be rewired correctly? I've had many Ampeg hum pots that are intermittent, especially if there was ever a shorted output tube. You may have a bad hum pot. With the amp off, measure from ground to each side of the pot while turning the shaft. Each side should go to ground. I usually change the hum pot it is not 100 percent solid.