[codefox1]

I believe I have a model 432 Musiphonic from 1953 or 1954. It is to the right of the absoloutely georgeous Philco 48-464 on tha attached photo. I got them both in a package from Ebay. (The Philco was re-capped, cleaned and georgeous, I'm keeping that one.) Anyway, this little GE "mutt" is a 6 tube printed circuit dog's breakfast of a radio, but it does have a RF amp, 3 gang tuning capacitor, kind of interesting output transformer with a feedback winding, and the cabinet is perfect.

I recapped and cleaned the "mutt" (all the filter, bypass and wax caps) and I know I will have to replace the 35C5 socket, but there is an intermittent problem downstream that is shorting the B+. I tried blasting out the IF cans with Deoxit 5, and did a thorough decontamination of the pc board via mineral spirits brushed and wiped with paper towels, and left to dry for several days.

After that I was able to pull a couple of stations in, weakly, with garble and static, and current surges visable on the pilot lamp, and decided to stop before I burned the little sucker up.

The previous owner was, it seems, a rat who smoked. Now I am of a rat year (1948, and I smoke.) so that should not alone sentence this little box to death, or dismemberment to the crazy house of my spare parts.

I need a schematic, and would be very grateful if anyone has one and can make me a copy, or has tackled and won, or has tried and failed on one of these.

Thanks

Bill (AKA Codefox)

[rghines1]

Schematic emailed.

[codefox1]

Richard

Thank you so much. I should be able to bring this puppy back to life. I hope I can return the favor some day.

We certainly have an excellent resource at hand in this forum (or Phorum.)

I hope everyone enjoys a happy holiday season.

Bill

[codefox1]

It lives. I could write an obsolete book on how to not make a radio, and this model would be mentioned in every chapter. There is good sensitity and resaonable selectivity but the mutt of a printed circuit and point to point wiring make it a nightmare to work on. Jury's still out whether the buried capacitors in the IF cans are OK. Don't know how to get the cans off without a chainsaw. Cabinet responded well to brasso, and now shines like a "I an see my whiskers." Now what. does sanyone want it? Will burn it in a few more hours then it's off the bench and on to the shelr.

[rghines1]

Congrats!
Haven't worked on a tube radio with a printed circuit board. Hear they are prone to have broken traces, etc. Don't know I could have persisted to a successful conclusion. You'll want to keep this one and put a note inside on everything done for the next owner to ponder.

Richard

[codefox1]

Thanks to all. This set was a challenge. The wax capacitors melted everywhere and combined with smoke and grease to form resistors between the traces on the circuit board. And this gunk was cooked into the tube sockets, especially the 35W4 and 35C5. I went over the board and touched up all the traces and connections. I attacked the circuit board and chassis with paint thinner and a tooth brush and blotted with paper towels until all the gunk was gone, then blasted Deoxit on everything. The push pull on-off switch was intermittant, and needed to be disassembled, cleaned, and re-assembled. The (main) spot-welded wire to the chassis was loose. I had to resort to cardboard soaked in deoxit to clean in between the blades of the variable capacitor, and disassemble all the trimmers to clean the micas. I blasted the if cans three times before the fluid coming out was the same color as going in. It took a while to align after all this.

Surprisingly the kitchen grease and smoke deposits helped preserve the plastic cabinet, original line cord, and even the plug. The few scratches came out with a good rub with brasso. I could have polished the chassis better, but this was turning out to be a crusade, not a project.

The only thing remaining to do is fix the knobs which have rough outer edges. I am patiently building the edges up with coats of clear nail polish. Then I'm done, and can get this off my bench, so I can finish up the 2 Philcos.

I'm learning a lot of new things by reading the Phorum threads, thanks to all for the help.

[Jim Berg]

Sounds like it must have been a kitchen radio. The old PC boards get pretty bad around 35W4 and 50C5 due to all the heat. You should not need a chainsaw to get the IF cans off, as an air chisel should work just fine.

[Texasrocker]

A couple good pro-tech fast-cleaners I have found in the past for these type "heavy" cleanups are in spray-cans avail from electronics supply houses. One is called "Blue Shower", and the other is " Big Bath". Either type quickly removes, disolves, ALL dirt, grit, grease, etc type debris accumulated over many yrs. It dries very fast, and leaves printed circuit boards,metal chassis, etc looking like new! Just make sure you dont accidentally get the overspray on other various type plastic parts, such as dialcovers,dialscales, cabinets,knobs,etc. The cans have instructions, and are abit pricey, but a can lasts a long time, and saves many hrs of chassis cleaning labor indeed!

[Arran]

I've been cleaning chassis of late with a solution of TSP, about a tablespoon to a gallon of hot water. First, remove the dial, speaker, tubes, and anything else that might be in the way or get damaged. You then slather down the chassis with the solution, sometimes even poring it over it, let it sit for a few minutes, then scrub with a toothbrush, then you rise everything down with hot water and sit it someplace warm to dry for a week. I haven't tried it on a PC board but it removes filth from a steel chassis very nicely, plus has the added bonus of shining up the aluminum and copper.
With regards to what may be loading down the B+, I would check the tubes, there could be an intermittent short causing the problem. I would also take a look at some of the resistors and the pilot lamp socket, one of those may be acting up.
Happy Christmas
Happy New Year
Arran