The PHILCO Phorum

This is a timely thread for me.  I have had a Philco 38-116 in various homes for over 50 years. My wife liked the cabinet, and nostalgia look however it was never even plugged in to power.  I am now retired and looking at the console one day, I thought perhaps I will take a look at it and see what it might take to fire it up. I mentioned it to my wife and she was overjoyed with the prospect of it actually working, so now I am committed.

I thought this was an unmolested radio as it has been in my custody for so long.  Not so!  Back panel is missing, there has been an RCA type phono jack and switch added to the back of the chassis, and the capacitors under discussion in this thread are missing. Underneath I find a dual 8ufd tubular under the chassis which is wired in using electrical tape!  I can not see the working voltage on it, and the end cap is blown as expected.  The cans that were the original caps are no longer there. I have the schematic and see that these were originally two 8ufd in parallel.

So I am in the first phase of restoring this radio, and restore is too generous, as I really just want to make it work, and do so in a workmanship like manner.  I am sure most other Ecaps will need to be replaced. Not sure this is a sustainable hobby for me but want to take a crack at this one and have been surfing the net for guidance, and rather enjoying it. I am trainable and have some electronic knowledge so any guidance or pitfalls with this particular chassis would be greatly appreciated.

Congratulations on your new adventure. You don't say what previous experience you have doing electronic repair. If you are a novice at such work you will find a lot of information and help here. If you don't have one, I suggest you buy a Weller soldering gun. The model 8200 is ideal for our work. The kind of irons used for printed circuit board work do not produce enough heat to work efficiently on these old radios. If you buy an 8200, get one with the NUTS to hold in the tips, not the new kind with set screws. This means buying a used one, which you can find very reasonably on ebay.

You can find the service information for your radio right in the library section of this site, https://philcoradio.com/library/download...l.%202.pdf .  This is the actual Philco service information, well scanned.

You say the original electrolytic condensers are missing from the top of your chassis. Did they leave the clamps for them? If so, you can make decent reproductions fairly easily, and clamp them in the proper place, leaving your radio looking more like its original self. Here is a link to one of my own restoration projects where I explain how I do it. https://philcoradio.com/phorum/showthread.php?tid=22318  

Besides the soldering gun, you will need a number of hand tools, needle nosed pliers, wire cutters, hog nosed pliers, etc. You'll figure that out as you need them. You will also definitely need a decent multi-meter. Good ones can be had reasonably from many sources. I bought the one I use the most at Harbor Freight. You will need this to check resistors, and voltages. With some you will also be able to check condensers. (Oh, don't mind me, I'm old and still call them "condensers" because that was what I learned, today most folks call them capacitors.)

More advice, replace all the paper condensers, and all the electrolytic condensers. There are a number of sources. I primarily use https://justradios.com/  and  https://www.tubesandmore.com/  and  https://www.oldradioparts.net/   Mark has all kinds of parts, and is an excellent source for hard to find potentiometers. Also check the resistors, and replace any which have drifted out of tolerance over the years. Most will be +/- 20%, some will be +/- 10%, and rarely you may find a +/- 5%. If you don't know the resistor color code You will need to learn it. Here's a link to a good page about it https://www.teachengineering.org/content...v1_dwc.pdf   There is a horse for remembering the numbers each color represents. It goes...  BAD BOYS RAPE OUR YOUNG GIRLS BUT VIOLET GIVES WILLINGLY, GET SOME NOW  . That stands for, Black, Brown, Red, Orange, Yellow, Green, Blue, Violet, Grey, White, Gold, Silver, None . Black = 0, Brown = 1, Red = 2, Orange = 3, Yellow = 4, Green = 5, Blue = 6, Violet = 7, Grey = 8, White = 9, Gold = 5%, Silver = 10%, None = 20%

So, that's a start. I hope this is of help. Welcome to the site and to the hobby. Be warned though. Once you restore this radio, you are liable to find it is addicting. Many of us have a house full of antique radios at this point.

These posts have been split into a separate thread by admin.

I just thought of another help if you are starting out on repairing these old radios. Right here in the Library section of the main site you will find this... Everybody’s Radio Manual: How to Build and Repair Radio Receivers  . It is good reading. I have a hard copy in my own library. It will teach you a lot about the basics. It is an old book, from the period when these radios were built, so it is well suited to the receivers we work on.

I just looked at the documentation of the 38-116. There are actually 3 electrolytic condensers used in the power supply. Two, part 141 and part 142 are simple 8 MFD electrolytic condensers. Part 140 is more complex, a 2 section electrolytic with both sections in one can, with common negative. BE CAREFUL when wiring these condensers. The negatives of all three DO NOT GO TO CHASSIS GROUND ! If you make your reproductions as I show in the link I gave you this won't be a problem since you will have both the positive and negative leads coming out of the bottom, and can easily connect them as required. All three negative leads connect together (eventually, not necessarily directly) and to the green and yellow wire from the power transformer, the HV secondary center tap, and to one side of part 128, the 490 K resistor, one side of part 134, the 3 K resistor, and the blue and white wire to the speaker field coil. Looking at the circuit, I see no reason why you cannot use 10 MFD axial 450 V or better 500 V condensers for all 4, parts 141 and 142, and both sections of part 140. Also, since both sections of 140 will be 10 MFD, you can wire either positive lead to either place and be OK. Again, hope this helps you. Feel free to ask questions. If I can't answer, I'm sure someone else here will be able to.

Mike,
Thank you so much for all the info.  I have now downloaded the schematic and see most of what you are discussing.  My model, it turns out is a 38-116, ver.125.  I reviewed your link for fabrication of the Ecaps and looks doable for me.  I do have a moderate skill level and tools, but it has been a while since I have used much of it, more focused on vintage cars and motorcycles. In regards to soldering equipment I have one too small and one too big. A newer Weller for PC board level stuff, and a vintage QuickHeat that I think is about 250 Watts. I have an older Philips scope, a Simpson 260, and a Fluke DMM.  I just need to get to work.  I have ordered Ecaps from the site you recommended.  Looking forward to the challenge! I have a NOS small Monarch Variac that I need to put in some case and do a little wiring.

Hi and welcome to the Phorum. Nothing like putting life back into an old friend. One of the first things you'll want to do is measure all the coils and transformer windings for continuity, including the speaker. They are probably the hardest things to source if there is an issue. Universal audio output transformers are easily available but the rest are tricky. So you'll want to know right away what you're up against. Above all, go slow, take pictures (both for yourself and us) and have fun.