[Coco] OT- Old Radio Help Request

KnudsenMJ at aol.com KnudsenMJ at aol.com
Fri Mar 26 11:32:20 EST 2004


In a message dated 3/26/04 6:07:40 AM Eastern Standard Time, 
spam_proof at worldnet.att.net writes:

> In my particular case, I'm getting a hum.  The shopkeeper said they could
>  pick up a radio station with it, but I sure can't.  I haven't taken it
>  apart yet, but I suspect that they've used wax capacitors, which decayed
>  over time and became conductive (I've had this problem in some of my other
>  radios).  The tubes seem to be fine.

Right, the wax paper "firecracker" caps are probably leaky and should be 
replaced.
Also so should the electrolytic caps, the big aluminum cans.   You probably 
know that the originals should be left in place for looks, but new, smaller 
ones should be wired underneath the chassis, after disconnecting the old ones.

You're also right in that the tubs are usually not the problem.  An exception 
is there may be ONE bad tube, which is why the radio was "retired" 
originally.  But it's a miracle how glass and metal tubes have held their hard vacuum 
for 50 to 80 years!

Hope your record changer is working so you can spin some 78s.  Probably have 
to replace the pickup cartridge; those are almost always dead.
--Mike K.



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