[R-390] triple mica tubes

[Tim Shoppa]

Scott Bauer asks:
>  Is there a certain place in the R-390A or R-390
> that would benefit from the use of a triple mica
> 5814A or 6189? Or will any old garden variety
> work.

I think that "triple mica" is related to "low leakage",
and low leakage is always a good thing around the
AGC caps, ...

BUT in every single case where a bad tube caused
me some AGC heartache, it was not just leakage but
a gassy tube. So I can't see any obvious advantage.

Just as a side point: I recently found out that the
5814A at one point a half century ago was specced
for some folks down the road from you - ARINC.
(ARINC has a nice little museum sponsored by
their radio club near the lobby of one of their
Annapolis buildings, too.)

Tim.