02-01-2017, 05:55 PM
I just had this radio out and cleaned the control. It played on the bench for three hours, no problems. I reinstalled it in the cabinet and continued to play it. While the volume control is working normally, I have noticed that randomly the volume will drop slightly. If you leave the radio alone it will suddenly come back up. If you raise the volume with the control, when it drops, when it comes back it is way too loud for comfort. I have monitored the output tube bias on the 71's and that stays constant so it isn't a problem with the transformer. I am not able to get to the 27, first audio to monitor any voltages. I have substituted all of the 24's and the 27 with known good tubes and that isn't helping. Thanks guys.
