[Boatanchors] Ceramic disk caps

[Carl]

Discs give far superior RF bypassing and I use them just about 100% 
there. Exceptions are some 30's radios house radios using the 78/6D6 era 
or earlier glass tubes where a little shunt inductance helps stabilize 
RF and IF amps at times. There is a workaround using ferrite beads and 
small value carbon resistors to do the job.

Some say that ceramic caps can cause distortion when used in audio 
coupling but I havent been able to notice any at the low levels of 
single ended stages. To play it safe I use film caps with PP stages. 
There is a series of scholarly papers on the subject out of the UK that 
claims all caps are prone to distortion and some ceramics are fine.

I dont use OJ's, cant stand the color and bulk of them. Discs and 
smaller films make for a much less crowded appearance that blends in 
with the resistors and wiring. I use neutral color brown films and not 
the glaring yellow ones which also look so out of place. Personal 
preference; I wont buy a radio that uses OJ or yellow caps.

Carl
KM1H


----- Original Message ----- 
From: "WØQFC" <erastber at tampabay.rr.com>
To: <FLBOATANCHORS at yahoogroups.com>; <boatanchors at mailman.qth.net>
Sent: Tuesday, March 03, 2009 10:19 AM
Subject: [Boatanchors] Ceramic disk caps


When rebuilding  boatanchor gear, is it ok to replace the ceramic disks 
with
"Orange Drops"?

In what case would it NOT be ok?

For example, parts list shows a .002 disk as a screen grid bypass. Is a
Orange Drop ok here?

Or, does anyone know of a good source for the ceramic disks?

TIA es 73
Gene, WØQFC

Stuff for sale: www.w0qfc.shutterfly.com
Web site: www.w0qfc.com

AF&AM #91 Lafayette CO

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