Amps
[Top] [All Lists]

[Amps] Possible Plate Blocking Doorknob Capacitors

To: <amps@contesting.com>
Subject: [Amps] Possible Plate Blocking Doorknob Capacitors
From: philk5pc@tyler.net (Phil Clements)
Date: Wed, 11 Dec 2002 11:14:57 -0600
> Are Sprague 715C-Z 1300pf 15kv doorknob capacitors
> suitable for Plate Blocking caps in an HF amplifier
> utilizing about 3KV plate voltage?  I was concerned
> about their ability to carry the current 80 thru 10
> meters.

To my knowledge, Sprague does not make any RF rated
door knobs. There are probably 1000's of amps sitting out
there today with the old TV-type door knobs just humming away.
In the "old days" we just went down to the local TV repair shop
and bought them for amp projects. Of course, the power levels
were well below 1kw back then.

The give-away clue with door knobs is that an RF rated unit that
is also rated for 15 kv would be HUGE, and have very large threads
in each end. The exception to this is the Russian/Japanese micas
that look like ceramic units, except for the plastic casing. They usually
have metric threads equivalent to about a #10 size.

The "killer" of door knobs is 12-10-6 meters, where RF current is
higher through them than on lower freq. bands.

(((73)))
Phil, K5PC




<Prev in Thread] Current Thread [Next in Thread>