[Stevelog]

I recently became the owner of a Philco console 42-390, saving it from the dumpster.  It is missing the speaker. It uses a dual 41 push-pull amplifier for its output. I believe it had an 8" speaker.  I have not been able to locate locate an original speaker and transformer(36-1552-4; 32-8120), so I probably will have to install a PM speaker in its place.  Does anyone know what the measurements in ohms is for the field coil and voice coil?  I have a coil winder and have had good results winding new voice coils and field coils for for my Crosleys. Also, it would be of help to know what output transformer should I use as a replacement? 
Any help or advice is appreciated.

Thanks, Steve

[GarySP]

Welcome to the Phorum, Steve! The Philco Radio Library located at the bottom of the page has info on speakers and output transformers under the parts section. Perhaps this will help. Take care and BE HEALTHY! Gary

[Stevelog]

Thanks for that information. It would appear from the output transformer parts list that the transformer that was originally on the speaker is #32-7968. Year would be 1939. Goes with a push-pull output using two 41 (6k6GT) tubes. A closer examination of the very small print schematic indicates that the speaker is a PM type. The ratio specs for the transformer is 16,000 and 1.25. I assume that this is for the primary and secondary windings. Does this seem reasonable?

[Stevelog]

Using a 5W  1.5k  ceramic resistor in place of the field coil and using a 4 ohm PM speaker, I was able to bring the radio to life today.  If I cannot locate an original speaker, I will wind a FC for 1100 ohms. The resistor replacement cannot be a permanent solution.

[morzh]

>>A closer examination of the very small print schematic indicates that the speaker is a PM type.


http://www.nostalgiaair.org/PagesByModel...013535.pdf

This shows a Field Coil time, not a PM.

>> If I cannot locate an original speaker, I will wind a FC for 1100 ohms.

I do not understand. What field coil are you talking about, if your speaker is a PM one, and you do not have the original?


As for the ratio, seems reasonable. Class AB load is 12K, so 16K is plausible. Your transformer then should convert 1.25 Ohm into 16K.

[Stevelog]

#87 on the schematic. 
This radio had a 8" Zenith  speaker attached to it when I got it. I do don't know the history of the radio, but it was a terrible mess. Mice had eaten some of the
caps and everything paper and felt. Even the dial cord! This radio had been used as a mice condo for years, and stank to high heaven!  There was a large mitten on top of the chassis and inside the chassis. I know this is common with these old sets,especially consoles, but this topped them all.
I knew something was wrong with the way the the original cloth wires to the speaker was wired, so after taking the radio out of the case and cleaning it, I then noticed it had the output transformer under the chassis. Knew someone had botched this together because the Zenith speaker also had an output transformer.  I did not have a very readable schematic after paying $8.00 for on from AES. Anyway, I now have a more readable schematic and it was because of that I found the field coil on the new schematic and it's readable resistance value so that I can rewind a new one.
I have a few more caps to replace, then repair and refinish the case, and this will be a nice console. I would like to get an original speaker though. The band slide switches are a mess-caked with dirt and gunk, but I am cleaning those with electronic contact cleaner from AES.  Could not get reception on any band until I used the spray while pushing the buttons. Reminds me of the band tower on Zenith TO's.
As to winding new field coils on these old sets, I have had great success with replacing the speakers with PM type and hanging the new field coils inside a small tin can and hiding it in the case somewhere inconspicuous. I had to do this on a couple of Crosleys in my collection. Has anyone else on the Phorum done anything similar?