Model 20 weird volume issue - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: Model 20 weird volume issue (/showthread.php?tid=26234)

---

Model 20 weird volume issue - WallaceRoger - 01-25-2026

Long term, I've planned to replace the volume control in my model 20. I finally found a good original and it went together just fine. There seems to be two different styles of volume control in these as I've seen photos of radios with the one I had as well as the one I bought. They both appeared to wire up in similar fashion but the stages were swapped and the old one had a bridge between the first and second stage that the replacement doesn't.

One issue remains, but has improved since replacement. When powered up, the volume is very low. Turning the control increases it but it's still very low. However if I touch my finger to the control, the volume immediately is nice and strong. Here's a video clip demonstrating what's happening.

https://streamable.com/1ayjng

I tried swapping the screen grid tubes with a spare I have with no change.

The issue exists regardless of whether I ground the chassis or not or use an antenna or not. 

Any ideas?

---

RE: Model 20 weird volume issue - morzh - 01-25-2026

This is quite normal.
The volume pot is isolated from the chassis, and the shaft gets close (not sure if it is connected) to the resistive element which connects to antenna.
This will almost disappear once you put the knob on that shaft.
And also, when you hook up a good antenna to the set, your touch will not have the effect this strong.

---