[R-390] killer cap and mica in RF?

[Guido Santacana]

The killer cap is C553 under the IF deck. Now, about the mica cap that
causes failure under 8MHz I want to know too. Replace all .1 and .033uF
bumblebee caps under the IF and RF sections. Those are probably gone by
now. The main multisection electrolytics in the audio deck may reform but
be careful and also check the tantalum cap under the audio deck. The best
thing is to replace it with an electrolytic. C551 is the big 2uF cap
mounted on top of the IF deck. It is a usual failure item and can be
replaced with a new smaller one installed under the chassis. I just went
through resuscitating an EAC unit that spent more than 30 years in storage.
Hope this helps.

Guido

Guido Santacana KP4FAR

On Mon, Oct 10, 2016 at 12:27 AM, Chuck Collins <chuckcollins at prodigy.net>
wrote:

> Plodding along on the 10 year owned R390-a restoration that has been
> ignored way too long. Which is the killer cap I hear about and which mica
> fails most often in the under 8mhz RF?
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