Rusty,
here are a couple of things to try, initially. By the way, it sounds like you have a nice lab supply that you are using.
First, is the volume low for all areas of the band? Second, have you tried all three positions of the tone knob. Maybe one position is faulty. Third, there is a small trimmer capacitor, which can be adjusted from the outside. It is located just under the antenna. See if that makes a difference. That capacitor is supposed to help match your antenna to the radio.
