Vintage Transistor Radio Repair?

[Bobbr]

Greetings everyone.

I've worked in commercial broadcasting and a/v production for most of my adult life, and I'm a licensed Extra-class amateur radio operator. I have some vintage transistor radios from the 1960s that are very special to me, and they're not performing very well anymore. They probably need to be recapped, but I just don't have the time to troubleshoot and repair them myself, let alone hunt for replacement components.

Can anyone point me in the direction of people who might be able to refurbish these little gems? Magnavox and Bulova are the brands, so I know there is service documentation out there.

Thanks for any advice you can share!

Bobb
KB3ZIM

 

[kimbear]

The biggest problem is the Geranium transistors that are NOT IMPOSSIBLE, but difficult to find. I have powered up dozens of these little jems and found them all to still be working properly. The most common problem seems to be 9v battery snap replacement, and cleaning the volume pots.
I really don't think you need too much in the way of schematics, they were all pretty much a common 2,4,6,8,12 transistor design.
There was very little in them to go wrong with age, other than mechanical damage.
I guess that you could argue Electrolytics would need to be replaced...but again, every little radio that Ive put fresh batteries into has just powered up.

 

[Nigel Goodwin]

I guess that you could argue Electrolytics would need to be replaced...but again, every little radio that Ive put fresh batteries into has just powered up.

Electrolytics generally weren't a problem.

The most common failing on old transistor radios is the AF11x series of RF transistors, they commonly go S/C to the screen from one of the other pins (they are a four wire device) - a crude (but almost always effective) solution is to cut the screen wire.

 

[cowboybob]

... The most common failing on old transistor radios is the AF11x series of RF transistors...

Nigel, you've probably seen this article, but I found it a fascinating treatise on all sorts of early transistors.