I have a loud hum-buzz type noise from the power supply on keydown. When running CW it follows my keying like a second sidetone. HV -Grid-Plate readings all seem normal. Am I looking at replacing a power transformer or ??? Thanks.....73 Ed W3NR -- FAQ on WWW: http://www.contesting.com/FAQ/amps Submissions: amps@contesting.com Administrative requests: amps-REQUEST@contesting.com Problems: owner-amps@contesting.com