The PHILCO Phorum

I finished restoring this nice model 16 Tombstone. It has a tone coming through the audio much higher than power supply hum. I would describe it more like an audible note or tone. All Bakelite blocks recapped, New filter caps. There were a few dog bone resistors out of range so I replaced them. The radio plays fine otherwise. Shadow meter works good. Alignment went well. Any ideas would be appreciated. Thanks, Mike.

Fixed it. I started grounding the grids of the 42 output tubes, no change. Then the 42 second audio, no change. Then the grid cap of the 77 first audio no tone noise. I replaced the 77 first audio, problem fixed. No noise, radio plays and sounds great. Thanks to all that looked at this thread. Mike

It is also possible the 77's grid cap wire was outside of the shield and not inside, and while replacing the tube you put it back inside.