[PhilcoPhan1936]

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.  

[Image: https://farm5.staticflickr.com/4694/2612...47dc_z.jpg]

[PhilcoPhan1936]

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.

[morzh]

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