[R-390] IF deck caps

[blw]

> I know the failure rate of Black and Brown Beauties, but do the yellow
> Aerovox jobs suffer a high failure rate too? I ask because I just (groan)
> looked at the nearly 20 of them packed into the underside of this Teledyne
> IF deck that will require replacement if ALL the paper caps must be changed
> out. Some of them are pretty well buried. My other 390A, which was gone over
> prior to my purchase by a fairly well known rebuilder, had only C-553 and
> the BBOD's replaced, all the original yellow Aerovox's were left in. Was
> this a bad move on the restorer's part? That particular radio has worked
> like a champ for 3 years now.
> Jerry W5KP


Jerry,

Are you talking about wax covered paper caps?

If so, these have to go. They leak badly. These are good candidates for
reforming as you bring a variac up slowly, but you will probably find a high
number of them out of tolerance. These get pinhole leaks in the foil
innards. You reform them by bring up the voltage slowly and the holes get
filled again. But, you can guess the probability of failures soon with that
many of them in there.

Pull those wax covered paper caps out carefully and put them up for sale on
ebay. Advertise them as excellent dummy caps for the *L@@K* crowd who cover
modern caps with the shells of old ones to make it look *ORIGINAL*. Don't
laugh, a lot of people do this. I was just reading an old article about a
guy who forms his own square molds for the old type resistor look.


Barry