[NostalgiaRadioTime]

Good idea, Terry. Just tried that...took it up to 32.1 VDC with the variac and set on. Unfortunately, it made no difference in the buzz. It's still there. So, figuring if nothing else I can eliminate that possibility, one by one, I tried swapping tubes with known good one's. This too made no difference in the buzz. I'm at a loss as to what the cause could be. I would think if it were some sort of interference from the transformer itself the buzz would manifest itself steady across the dial. Not drop off after 1100. Any ideas on what to try or check next?

The buzz does get louder when the antenna is connected verses when not. If I hold both the antenna wire and ground wire in one hand....with neither wires touching or connected to anything else...and then touch the shielded cable going to the power supply cylinder, the buzzing gets a bit quieter.

Couple of other questions....could the transformer itself that I'm using in my power supply be causing the buzz? It's not a signal transformer, as I'm still waiting on the one I ordered that got lost (it was found in California and is en route again) but just a standard 120V / 24V step down transformer that is probably less than 50VA.

Also, I replaced the caps in the power supply with the values of the original caps inside. I know they were the original caps, as they match the style and size of the caps under the chassis and showed no signs of ever being replaced. I went by the values on the caps themselves (.1 and .25 's). On the schematic, it shows double the value that were in the power supply.... .25 and .5 's. Could that have anything to do with the buzz?

Sorry for all of the questions. I'm stumped on this...never dealt with a 32 volt radio before or with a vibrator power supply. I can't thank you enough for all of your help and continued patience.