[frankie-d]

gentlemen, I am at my wits end, i have recapped about 20 old radios of many brands and all i have is a multimeter, i have ordered a tube tester and now  my problem is my 40-180, it has a loud hum and no audio before i changed the caps it had a very low audio, and now no audio, i am just a beginner and i happen to like old radios, i would appreciate any advice you can give. thank you... Frankie Deramo

[morzh]

Frankie

Other than the caps, there are many things in radios.
You could measure voltages and see if all plate voltages are present, for starters.
Also, check all resistors, check all wiring (40-180 is exposed to rubber-jacketed wire plague, where it cracks and falls off), and then check all the coils for continuity.
Then, if you did wire replacement, parts moving: make sure the wiring is still correct.

[klondike98]

Hi Frankie, Welcome to the Phorum!


So everyone is on the same page, here is the schematic from our online library for this radio:
https://philcoradio.com/library/download...20Book.pdf

The most likely cause of it working, even badly, before recapping and not working afterward is that something got rewired incorrectly. Recheck your cap replacement wiring by following the schematic. A common problem is people do not rewire the filter caps correctly. Check cap #61 (12uF electrolytic cap) that you have the polarity correct. The Negative side of the cap goes to the center tap of the transformer while the positive side is connected to Pin#4 of the 84 rectifier tube and one side of the field coil (#62). The other filter cap (#58) negative is connected to chassis ground and the positive to the other side of the field coil (along with other places in the radio). Keep in mind the schematic is an 'electrical' representation of the connections not a physical representation of wire locations.