[camateg]

Hello -

Please go easy, as this is my first post. I have a nice Philco 46-1226 and I am very confused as to some specifics of the design.

I have the following references:

- Ryder's schematic for -121 model
- Sam's schematic for (???) model

The two differ considerably from what I can see, likely due to the difference in models that they represent...

The problem with the radio initially is that the two 10W power resistors were "open" and non conducting and I am not sure with which values to replace them. Being open, I could not measure them and although they had Philco numbers on them, I am having trouble reading those.

I guess my long-prefaced question is:

What 10W resistors are present in the -125 near the power transformer to form the B+? Or, failing that, is it possible to look up the Philco resistor numbers somehow?

Thank you very much for any assistance.

Matt

[camateg]

In retrospect, I think that the 121 was correct, based on another person's description of a 125 on this forum. Sorry, but I can't seem to be able to cite it at the moment...

To further complicate matters a bit, it seems that the voice coil was replaced with one of the two resistors in question. I replaced it with a 680ohm, 10 watt and I replaced the other 10W resistor according to the value in the schematic, respectively, though I cannot remember the value now at the computer! Sorry for my vagueness...

In any case, the 680ohm seems to run a bit hot, but I have been listening to it for about 45 minutes now and it continues to run reliably and sounds consistent, aside from a detector with perhaps some dirty pins!

This is a nice radio and 2nd Philco still present. The other is a 1936 whose cabinet is being restored for me at the moment.

Thanks!

Matt

[rghines1]

Hi Matt,

Sounding like the speaker as been replaced with a permanent magnet type. The 680 ohm resistor must be standing in for the open field coil of the original speaker. The field coil is part of the power supply and the electromagnet of the old speaker. That resistor will carry the B+ current and dissipate about 5 watts and will burn your finger. You need to consider recapping the entire radio which is a major job. A cap failure likely burned out the field coil.

Richard

[Ron Ramirez]

Hi Matt

You are correct in that the speaker was changed to a PM type in Code 125.

There are too many changes for me to list them here. I'll scan the changes and post them later.

You really should ask Chuck if he has the service data for this model. With every schematic you purchase from Chuck, you receive all of the pertinent information for that model including production changes. The $7 fee is well worth it.

http://www.philcorepairbench.com/schematics.htm

[Ron Ramirez]

Click the thumbnail below to see a larger picture:

[Image: http://i326.photobucket.com/albums/k420/...26ch_1.jpg]

This scan combines two pages of changes to Model 46-1226.

[camateg]

That makes sense now, thank you!

It looks as though the electrolytics were replaced in the 1960s or onward, which confused me at first because the 10uF and 25uF were simply combined as one (C101) on my specific set...

I think the thing(s) to do now is to replace the 680ohm resistor with a 1300ohm, which I had thought was the "dummy field coil" and to re-introduce the 300ohm in series with the transformer output. Fortunately, I had already ordered those components rated at 10W a couple of days ago based on the Sam's.

Also, the new part numbers appear to be right on for the open resistors that I have lying in front of me in the parts list, a + c...

I had also (prior) replaced the electrolytic capacitors with modern equivalents and the wax capacitors with the orange drop type without polarization.

I will await the arrival of the proper resistor values and let you know how things continue to progress...

Thanks!

Matt

[camateg]

I got it all put together yesterday and it works even better than when I had done it "improperly!" :-) Surprise, surprise!

All caps are now replaced, as well as out-of spec resistors and tubes have been checked, etc.

Now my goal is to find some knobs and a phonograph cartridge, as the one that is in it does not seem especially good and does not consistently produce good sound. :-/ I don't know much about phonographs, but that's what the Internet is for, particularly this forum, where I appreciate everyone's help...

I may have enough knobs from past Philco "disasters" when I was mostly learning, but I need to find a way to fabricate those little metal inserts.

I will try to place a picture. It was not a bad find for $20 and $20 worth of parts!

Thanks again, all!

[Ron Ramirez]

Congratulations!

Try West-Tech Services for the cartridge.

http://www.west-techservices.com/
The knobs are identical to 1942 Philco knobs, and reproductions are available from Radio Daze.

http://www.radiodaze.com/
You can make your own knob inserts if you have any of those old tins that fuses used to be packaged in. Cut a strip of the thin metal narrow enough that it just fits in the slot where the insert should go, fold it over a few times and VOILA - instant knob insert. Better than no insert at all.

[camateg]

I think I beat you to the punch on the knobs, but I ended up "recycling" a sub-par terminal strip. :-)

Regarding the phonograph, it ended up being the wire from the cartridge instead of the cartridge itself, so that was an easy fix, too! The phono is a bit quiet, still, but a signal generator comes through loud and clear, so I will perhaps keep your links for the future.

In a side note, when my 37-620 was finished, my friend had to remove the decals, so I ordered some from antique electronic supply. They were $5 / sheet and they are general enough that I can use them on most Philco sets. The 37-620 is turning out very nicely from a cosmetic standpoint and I will start a new thread to "show it off" if that is permitted in an appropriate category.

I have to say that this is the first time I have found a forum to be useful. Perhaps I was not "doing it right" in the past, but I definitely thank you for this one, because you've been very helpful!

Matt