View Full Version : Converting an old Studebaker car radio to a home radio


radiotvnut
09-19-2012, 03:15 PM
Here's an old Studebaker car radio that I picked up. My intentions are to mount it in some type of cabinet and use it for a table radio. Now, I have to decide rather I want to build an outboard 6V power supply to operate the radio or rip out the original transformer, vibrator, and rectifier and replace those parts with a standard power transformer and rectifier. Anyone else ever done something like this to an old car radio? BTW, the model number is S4923 (Philco). I remember reading an article in ARC where someone converted an old Ford car radio to home use by ripping out the original DC power supply and replacing the components with a standard power transformer and rectifier from a junk radio chassis.

http://i538.photobucket.com/albums/ff341/radiotvnut/radiola33%20004_zps33875ec5.jpg

bob91343
09-19-2012, 04:59 PM
I don't recommend running a vibrator unless there is no alternative. They are noisy, of limited life, and hard to obtain.

Ripping out the transformer is an option, of course, but supplying AC to it is another. You would need a square wave power oscillator set to the frequency of design of the current power transformer.

My own solution would be to run the heaters from a filament transformer and build a little DC supply for the plates. There isn't much power involved so the whole thing wouldn't be very big.

I would, however, fix that dial so you can read it.

old_coot88
09-19-2012, 06:01 PM
When automobile production stopped at the outbreak of WW2, this same kind of conversion was done by Philco and Motorola to use up a stock of car radios..
http://www.philcoradio.com/phorum/showthread.php?tid=144

dieseljeep
09-19-2012, 06:18 PM
Here's an old Studebaker car radio that I picked up. My intentions are to mount it in some type of cabinet and use it for a table radio. Now, I have to decide rather I want to build an outboard 6V power supply to operate the radio or rip out the original transformer, vibrator, and rectifier and replace those parts with a standard power transformer and rectifier. Anyone else ever done something like this to an old car radio? BTW, the model number is S4923 (Philco). I remember reading an article in ARC where someone converted an old Ford car radio to home use by ripping out the original DC power supply and replacing the components with a standard power transformer and rectifier from a junk radio chassis.

http://i538.photobucket.com/albums/ff341/radiotvnut/radiola33%20004_zps33875ec5.jpg
That's exactly what I did 50+ years ago. I removed the original transformer and vibrator. I used the original rectifier tube, a 7Y4. They made a really good performing workshop radio. I even put a phono jack in mine. :yes:

wa2ise
09-19-2012, 09:23 PM
I'm not sure if the original vibrator step up transformer can operate at 60Hz, think vibrators of the day ran faster than that. But if this transformer can do 60Hz, you might be able to run this radio off a big "wall wart" 6V or 12V AC transformer. You'd remove the vibrator, and jumper out one side of the vibrator switch contacts. But I think that this transformer wants to see 100Hz or higher, and not like 60Hz. In that case, just remove the transformer and vibrator, and keep the rectifier tube. Hopefully, there's enough room to house a regular 60Hz power transformer that produces heater power and B+.

A less safe approach would be to convert the radio to a hot chassis design. If, and it's a big if, the circuits inside are not tied directly to the chassis (this might have been done to make the radio useable in a positive ground car and in a negative ground car). You'd change the tubes to their 12V equivalents, and the audio output to its 50V heater equivalent, and the rectifier to the usual hot chassis rectifier circuit.

dieseljeep
09-19-2012, 10:21 PM
The radios that had a non-syncronous vibrator would run on either polarity. If you look at the schematics in Riders, they show how to change the polarity connections if the radio did use a syncronous vibrator.
I've seen a radio that was powered by a large 6 volt transformer, that used only half of the primary of the vibrator transformer. It seemed to work OK.

Sandy G
09-20-2012, 07:06 AM
Restore the thing, spiff it up a little, sell it to a Stoodie freak for some OUTRAGEOUS price, & then buy a nice chairside..

dieseljeep
09-20-2012, 10:21 AM
A less safe approach would be to convert the radio to a hot chassis design. If, and it's a big if, the circuits inside are not tied directly to the chassis (this might have been done to make the radio useable in a positive ground car and in a negative ground car). You'd change the tubes to their 12V equivalents, and the audio output to its 50V heater equivalent, and the rectifier to the usual hot chassis rectifier circuit.[/QUOTE]

I saw this approach on a 4V31 Zenith farm radio. They used the vibrator transformer reverse wired, to provide the heater voltage and used a selenium rectifier for the B+, connected right to the line.
Hot chassis and a real hack conversion. :thumbsdn:

dieseljeep
09-20-2012, 10:24 AM
Restore the thing, spiff it up a little, sell it to a Stoodie freak for some OUTRAGEOUS price, & then buy a nice chairside..

Find one of those Philco chairsides, with the Mopar radio in it. :D

old_coot88
09-20-2012, 10:46 AM
...The radios that had a non-syncronous vibrator would run on either polarity.
As a side note, they would also run on 6v AC, albeiit with a nasty 'beat note' between the 60 cycle supply and the vibrator speed. (Been there, done that.):o

dieseljeep
09-20-2012, 01:55 PM
As a side note, they would also run on 6v AC, albeiit with a nasty 'beat note' between the 60 cycle supply and the vibrator speed. (Been there, done that.):o

I used my Lionel electric train transformer to run car radios at one time.

Einar72
09-20-2012, 11:23 PM
I tried hooking AC directly to a de-vibratored 50-51 Ford car radio once. I got a very loud SPLACK :sigh: as the copper "spark-plate" capacitor promptly did its job, routing the offending AC to ground!

BTW, most vibrators run at 110 Hz, IIRC. Pull the Sams' for that set and find the power xfr ratings, then go buy the closest one you can find. And watch out for the 1-1/2" square copper spark-plare, if used!

snelson903
09-21-2012, 02:57 AM
if that radio works and is all orginal [ wiring ] ,i rebuild generator's and starter's for the studebaker club over here in south bend in ,since rebuilder's dont seem to understand pos ground systems now days. that radio might be worth alittle money ,i could ask if interested and if it works ,i also have 6 volt vibrators i think 3 left for that radio.

toxcrusadr
10-01-2012, 11:55 AM
I was also going to suggest you leave it original and get it in the hands of a Studebaker owner. Which is not why you posted in the first place, so take it with however many grains of salt you wish.

I have a friend with a '52 Studebaker Commander, and I recapped his radio a few years back and got it running, and he was thrilled. Studebakers are not that common, and intact radios for them are even less common.

Just my 2 cents.