>From lots of prior experience and hair tearing: If you are not seeing 122 to 125 V input to the power supply, you are going to have problems. Get your primary set there and then worry about other settings. Also, most of the variacs folks are using are not large enough to handle the input current required by a fully loaded PS-7. As the load increases, the variac heats up and the primary voltage drops. Keep a meter on the primary input voltage at any time you are making adjustments and watch it carefully!
73,
John, W4AWM
