[Eric]

Philco 40-185



This looks original and not messed with so I started recapping one at a time and was very careful of the wiring which is very brittle. Tubes tested good my problem is this. Across #61 a 12uf electrolytic which I replaced with a 20uf I get about 200vdc but across 58# a 16uf electrolytic I replaced it also with a 20uf I get 0vdc. Now the field coil shows 1100 ohms and I get continuity thru the wiring. I have a second radio a 41-285 that I've not started and had the idea of swapping speakers as the resistance is the same but it didn't make a difference.

Now across the transformer black leads I have 6.3vac filament voltage

Across the transformer yellow leads which go to the 84 plate I get 227 to ground

What am I missing? Why no voltage on the #58?


Eric

[Radioroslyn]

Check 59 and 60 if open will cause that problem or if 58 is in backwards.
Terry

[Eric]

Will check 60, 59 in the morning. 58 is tied in with the NEG end tied to ground.
Thanks

[Eric]

Checked out 59 and 60 and there ok 59 is 16.6ohms and 60 is 160ohms.

Both neg on the electrolytic's go to the chassie but on 61 the case is insulated and 58 the case is grounded not sure why?


Now I get 0vdc when checking to ground but 25v when checked the the base of 59???
Any other ideas?

[Radioroslyn]

Ok then disconnect the wire that goes from + side of 58 to the screen grid pin of the 41 tubes. Now measure the voltage across 58. Should have 300v or so. The two resistors make up a voltage divider on the - side of the high supply, is provides the - bias for the 41's.
Terry

[Eric]

Terry
Found the problem and it was ME! Thought I was so careful doing the operations one at a time and I put a wire on the terminal next to where it needed to be. When I corrected that I got static which was music to me then hooked up the ant and other wiring and she plays!! Still have lost of work to clean up the chassie and the cabinet needs a lot of work but it should look good when I'm done.Thanks again
Eric