The PHILCO Phorum

I turned on my 1st complete restoration, my 1936 Philco 620B Tombstone, to listen to the local news late this afternoon, and got no audio.    Not even static at full volume.  

I recall the last time I turned it on, it worked for a minute, then went silent.  

Up to the last time I turned it on, it was my go-to radio to listen to. It's been an excellent performer, so I'm a bit surprised.  

So I'm pulling it down and 1st thing will be to pull and check the tubes.  

1st thing I checked was the output tube, the 42. It checked out OK. Next was the 78 (IF), also OK. 75 tested strong on all 3 tests. The 6A7 shows just a nudge under 300 on the OSC section, but my chart says OK if above 100. The Other 78 (RF) tested in the Red, low.

I pulled a 78 from my 620F, and popped it in, and the radio came right on and worked as it always had.

Then, just to confirm it was that tube, I popped the original back in, and it worked! Odd. I jiggled the tubes around, checked the grid cap connections, and it continued playing. Maybe it was just a loose connection somewhere.

For now it's working, so I'll stick it back up on the shelf.

I'll re-visit this thread if it acts up again.

Even if tube tests LOW, unless it tests DEAD it usually works, just not so well. With few exceptions, an oscillator might be one.