Kelley:
There's so much difference in the currebt versus resistance curves of
various vactrols that I really couldn't tell you what's right for your
Vactrol.
I've found data sheets for all the Vactrols I use on the web. The fairly
common VTL5C4 is at
http://optoelectronics.perkinelmer.com/content/Datasheets/vtl5c3_c4.pdf and
a Google search will get you any others.
When I do a controller for a Vactrol, I also insert enough series resistance
to guarantee I never put too much current through the Vactrol, nor more than
is needed to get the resistance down to a low enough point for me. As for a
maximum, that depends on what you want to use it for. To cover flags,
pennants, deltas, EWE's, etc I make sure the resistance will be 2K or a
little more.
There are a few articles at WA1ION's site (
http://www.qsl.net/wa1ion/bev/bev_remote_term.htm and others) where you can
find more information.
Chuck
----- Original Message -----
From: "Kelley" <kshaddri@myclearwave.net>
To: "TopBand" <topband@contesting.com>
Sent: Saturday, August 28, 2004 6:07 PM
Subject: Topband: K9AY Antenna Question
> I just bought a few vactrol's from B G Micro for use in my K9AY antenna in
> place of the fixed termination resistors. Looking at some older posts, it
> appears that the way to use them is with a 1k pot connected to the 12v
> supply. Is this how folks do this? There's really no documentation with
the
> vactrols, what about controlling current, etc.?
>
> Thanks,
>
> Kelley - WØRK
>
>
> _______________________________________________
> Topband mailing list
> Topband@contesting.com
> http://lists.contesting.com/mailman/listinfo/topband
>
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