[R-390] Ceramic .01 bypss buy

[Tim Shoppa]

Perry wrote:

> I'm starting to buy parts for my BA rebuilds.  I plan to buy either
500
> or 1,000 new Vishay .01 1KV ceramic bypass caps from Mouser to
> relace BBOD's in R390s and SP 600's.

Silly question, but: What possible effects could there be in replacing a
plastic-wax-foil type capacitor (BBOD) with a ceramic?

Certainly elsewhere in the 390A (esp. RF deck) there are plenty of 0.005
ceramic bypass caps.

Ceramics seem to have substantially less winding inductance but perhaps
substantially larger voltage-dependence in dielectric (I'm guessing that
a 0.01 1kV unit would by X7R or Y5P dielectric.) In bypass use it seems
unlikely that the funky X7R or Y5P dielectrics would have a lot of bad
effects but...?

Or: why did Art not use ceramics to begin with?

Tim.