I've restored several BC-348s, and Ken is absolutely right about the Micamolds. The good news is that they're readily accessible in the BC-348s. When restored, these are nice receivers and living slices of history. 

I'm attaching a link to Andy Moorer's page, which has the manuals for most of the BC-348 variants. 
http://www.jamminpower.org/bc348.html

                           Joe Connor

On Wednesday, August 10, 2022 at 11:22:49 PM EDT, Kenneth G. Gordon <[email protected]> wrote:


> On 8/10/2022 9:02 AM, [email protected] wrote:
> >
> > I hate to be the bearer of bad news, but the only satisfactory rebuild
> > of a BC-348 is to replace _every single one _of the Micamold
> > postage-stamp bypass capacitors which, by the way have nothing to do
> > with mica. They are paper caps, and they all develop leaks sooner or
> > later - usually taking out one or more associated resistors.
> >
> > Miles, K2CBY

I can absolutely attest to Miles' words on the "MicaMold" capacitors!! They are total piecs of
junk.

I have recently rebuilt two National NC-57 receivers, both of which were full of those things.
There were something like 15 to 18 of them in each receiver. I tested every one of those I
removed with my rebuilt Heathkit C-3 "condenser" tester and not one single one of them was
any good. Leakage was terrible in every single one of them. Some were a dead short.

After I replaced them all with 630 metalized film caps, the improvement in the way the
receivers worked was amazing, and the noise was unusually low.

I have a BC-348 here now which I bought recently off eBay, but have not yet touched. My
thanks to Miles and others here.

Ken W7EKB

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