Packard Forum Index » Post-War (1946-54)

I need a little advice on my radio... The power comes on, the lights on the dial work, the speaker hums, but it won't pick up a signal at all. I took it out of the car and opened up the back (hoping to see something obvious that needed to be fixed), but wow this thing is really old . Is there something simple I should try (replace a transistor) or should I just send it off to someone else? Any suggestons would be appreciated.

Don't think you'll find any transistors in there. Have you checked the antenna connection at both ends to make sure it is connected or center lead has not been grounded somehow. If that all looks good, then think a trip to repair shop is about all you can do.

Yea, guess those little vacuum tube looking things aren't transistors . Thanks for the suggestion, I will check out the antenna.

If it hums that means the power supply or vibrator must be working and the radio is trying to sing but forgot the words LOL.

Seriously, most times on old radios it is the capacitors that are at fault. They are made of tin foil and wax paper and yours passed their "best before" date during the Eisenhower administration.

Today you can buy replacements made of mylar that last a lifetime. They cost around 25 cents to $2.50 apiece and there are 10 or 20 of them in each radio.

There are millions of NOS tubes around. Most cost $5 or $10 new. There are some exceptions but they won't be in your radio. It will have common tubes in it.

The vibrator can be taken apart if you are careful. You can clean the points with some contact cleaner on a piece of white typing paper.

The insulation is probably falling off the old wires. So they may need replacing.

Fixing old radios is not particularly difficult. Parts are available and usually not expensive. It's the labor that adds up. Probably $100 to $200 to overhaul a radio like yours.

If you feel up to tackling it yourself there are web sites that specialize in old radios. The best thing to do is get a copy of the original wiring diagrams etc first. Sometimes you can get them for nothing but at worst you might have to pay $5 or $10.

I definitely recommend repairing your old radio or pay someone to do it. Please do not let someone gut it like a trout and slap in a transistor set!

If you want a CD player you can buy one at Walmart for $29.95 that will work on 6 volts and can be wired into your radio. I just bought one called a Magnasonic MCD3968 that even looks like a 1947 accessory. It has an FM radio too.

Maybe you know an old time radio hobbyist in your area who can help out. Or, there are repair shops that advertise on the net. You might even tackle it yourself.

Here is a website for Justradios who sell the capacitors and schematic diagrams.

http://www.justradios.com/oldcarschematics.html

Here is an excellent tutorial on diagnosing and repairing old car radios. This guy also has schematics and tubes.

http://members.cox.net/dcosby1/Autoinfo.htm.htm

In any case if you have any questions feel free to ask.

Magnasonic MCD3968

Rusty , Thanks I'll have to look into getting one of these so I can play period correct music. My 1947 radio needs a vibrator and some other work but here in the north country there are no longer any AM stations so not really worth the expense to get it working. I now have another 1947 I found on Ebay with an modern FM unit inside the box. It is 12 volt but I power it through a 6V to 12 converter and it works great.

Rusty,

All I can say is WOW! That article on how to diagnose it awesome. I am going to walk thru it before I take it anywhere. I would never think of replacing the guts since everything else is original.

I do have the original owners manual for the radio and have attached the wiring diagram in case anyone else may want it.

Finally, I did find an antique radio place here in Houston that can fix it, over the phone they gave me an estimate of $100-$200, so you are right on with that as well!

Thanks again!

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Thanks for the schematic page. There is a 47 Sams factfolder also in the articles section but unfortunately one page is partially damaged.

You mention having an owners manual for the radio. Any information on the radio operation and button setting would be appreciated as that is a question asked on occasion. Would you consider scanning that manual so it can be posted.

Here you go. The manual is slightly bigger than an 8.5x11, so I had to cut off a little on my scanner.

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Less, thanks again. It's been converted to a pdf file & sent to Kev so he can post it in the proper articles section. I'm sure we all appreciate your contribution.

One other possible cause of a lighted, humming, no reception radio is reversed polarity. The car battery is correctly connected using a positive ground... right? Probably not the cause, but that was the problem with my '50 when I got it. Just correcting the polarity fixed the radio.