06-19-2019, 08:17 PM
IMHO the extensive cleaning can and should wait. First determine if the power transformer is alive. Remove the 80 rectifier tube, examine the pilot light wiring for shorts. Tubes can be left in. Check the power cord for breaks that could short. Tape them up.
With the 80 out of the radio and all wiring associated with the power transformer in the clear but connected, power the set. The tubes should light, the transformer will fail almost immediately if it is bad or as long as 30 minutes. If the transformer is cool and no cracking, smoking after 30 minutes. The transformer is good.
Do not power the radio again until all restoration is completed.
Next check, rather, re-check the antenna and RF transformers. If any are open they must be rewound or replaced. The "Rule" is rewind as the Philco Ant. & RF transformers have celluloid layer insulation. This insulation decomposes and then corrodes the copper wire. There is no "solder-in" fix for this unless someone rewinds the coils for a hobby...
The final check is the volume control, ideally, the only check is an operating radio but if the control does not change resistance measured with an analog ohmmeter uniformly, it is likely "noisy" use a known control cleaner, not WD-40...
If the control is shot either a used replacement, again, iffy or a replacement from Marc Oppat. His specialty is controls and will have what you need.
Now clean and shine up, all the tough stuff is done...
There are a couple of procedures how to easily gut and repair the Bakelite block caps. Info on the web. These must be done as they are paper construction and are leaking.
Do take care of the 45 tubes, they are expensive to replace even for weak ones.
Do not re-route the wiring as changes could cause un-wanted oscillation. Replace any rubber covered wiring with similar size/type new plastic insulated.
YMMV
Chas
With the 80 out of the radio and all wiring associated with the power transformer in the clear but connected, power the set. The tubes should light, the transformer will fail almost immediately if it is bad or as long as 30 minutes. If the transformer is cool and no cracking, smoking after 30 minutes. The transformer is good.
Do not power the radio again until all restoration is completed.
Next check, rather, re-check the antenna and RF transformers. If any are open they must be rewound or replaced. The "Rule" is rewind as the Philco Ant. & RF transformers have celluloid layer insulation. This insulation decomposes and then corrodes the copper wire. There is no "solder-in" fix for this unless someone rewinds the coils for a hobby...
The final check is the volume control, ideally, the only check is an operating radio but if the control does not change resistance measured with an analog ohmmeter uniformly, it is likely "noisy" use a known control cleaner, not WD-40...
If the control is shot either a used replacement, again, iffy or a replacement from Marc Oppat. His specialty is controls and will have what you need.
Now clean and shine up, all the tough stuff is done...
There are a couple of procedures how to easily gut and repair the Bakelite block caps. Info on the web. These must be done as they are paper construction and are leaking.
Do take care of the 45 tubes, they are expensive to replace even for weak ones.
Do not re-route the wiring as changes could cause un-wanted oscillation. Replace any rubber covered wiring with similar size/type new plastic insulated.
YMMV
Chas
Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”
