[jlwiley123]

This is my first post - thanks for letting me join the group!!

Regarding my background - I restored/repaired a number of old radios in the late 1970's and early 80's, but have been away from the hobby for most of the last 40 years.

I recently picked up a Philco Chassis 91 code 123 radio. The radio is pretty complete, although I think it is missing one of the shields. The tubes are not all original philco branded tubes, so it has had some tube replacements in it's past. From looking under the chassis, I am pretty sure that there has never been any work done under there. All the bakelite blocks look original and the dogbone type resisters are still there.

I am pretty comfortable doing the restoration work to get the radio working again, and frankly that would be my primary interest - I don't really like display only radios - I want them to be functional.

All that being said - here is my real question: Would I be committing some kind of cardinal sin by digging into this radio - replacing all the paper capacitors in the bakelite blocks, electorlytics and any resistors that are drastically out of tolerance? Please let me know as I will probably dig into the thing in the next 2 or 3 days.

Thanks

   

[klondike98]

Welcome to the Phorum!


Replacing all the paper and electrolytic caps and any out of spec resistors is the right way to go. Some folks simply replace the paper caps with modern ones while others gut the old paper one, stuff the modern one in there, seal it with wax or hot glue and put it back in the circuit. It all depends on your preferences. I've done it both ways depending on how I felt about the radio. Aluminum can or copper electrolytics are pretty easy to gut and stuff but putting the new electrolytic under the chassis (after disconnecting the old cap) works also. My 91B electronic restoration thread is here: https://philcoradio.com/phorum/showthrea...#pid119958 and the cabinet is here: https://philcoradio.com/phorum/showthread.php?tid=17643 . Maybe there is something in those that is useful for you.

Those bakelite blocks can easily be stuffed as well. I usually take them completely out to stuff them and then solder them back in. Here's a service tip from our library on doing it without taking them out. https://philcoradio.com/library/index.ph...soldering/ ...and some bakelite block data from the library: https://philcoradio.com/library/index.ph...lock-data/

[KCMike]

Welcome. Answer to your question No, no sin here. If you was not going to ever plug it in than you could leave it alone but since you want to use it, yes replace the caps and whatever resistors need it.
The chassis looks really clean and I don't see any paper caps so it will look pretty original when you get done
with it. Good luck and keep us posted on your progress.
Regards, Mike

[Joe Rossi]

No paper caps in a Philco? What next?  Joe

[jlwiley123]

There are paper caps in the radio - they are inside the bakelite blocks. potted in tar.

[klondike98]

yep...see my updated post above with more info on those blocks. You warm up the block with a hair dryer, snip the wire connecting the paper cap to the block and pry the guts out of the block. then you simply put the modern caps into the block (no need to refill with tar), solder them to their correct leads and then put them back into the radio.

[klondike98]

If you are missing the Tube Layout label in the cabinet I just add one to our digital library at:
https://philcoradio.com/library/index.ph...out-label/

[jlwiley123]

Thanks - I do actually have that layout on the curved shield on the IF side of the chassis. The shield on the opposite side of the chassis is missing - pictures I have seen show just a single, flat piece of sheet metal shield in the clamp mount - is that correct? If your radio has that part, could you get me a rough measurement. I doubt the dimensions are criticle.

[klondike98]

Unfortunately I no longer have that radio so I can't measure it directly but I do have two photos that were not in the original Phorum thread that might help with the estimate. I think you are correct, the exact size does not matter, in fact, the photos I have of the finished chassis restoration seem to be missing that shield. I must have misplaced it and not put it back on. If I recall however the radio played just fine without it. Anyway here are the two photos from before the restoration. The gold model/patent label is 4" x 4" for reference. It looks to me the shield would be in the 5" x 5" range or so, or maybe a touch larger.