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Re: Topband: alternative to vacuum variables

To: Pete Smith N4ZR <n4zr@contesting.com>
Subject: Re: Topband: alternative to vacuum variables
From: Eddy Swynar <deswynar@xplornet.ca>
Date: Fri, 25 Jan 2013 07:42:39 -0500
List-post: <topband@contesting.com">mailto:topband@contesting.com>
On 2013-01-24, at 2:33 PM, Pete Smith N4ZR wrote:

> One of the reasons I have mot gone to high power on 160 is the cost of 
> capacitors for my omega match - at least $300.  Anyone know of any workable 
> alternative?  I remember someone writing about using coiled-up RG-8, RG-213 
> or maybe Teflon coax.  Where can I find more information?
> 


Hi Pete,

I've used a short length of RG-58 coax for just that purpose in one application 
here, to supplement the "C" from my air variable at the base of one of my 
extended inverted "L's"...

There's nothing at all wrong with that, I don't think, as long as the coax is 
simply "padding" existing C---I don't think you'd want to use the coax for a 
LOT of capacitance, though: if I recall correctly, one foot of RG-58 has some 
25-pfd. of capacitance---to get, say, 200-pfd., would you really want an 8-foot 
coil of coax in your system...?

~73~ de Eddy VE3CUI - VE3XZ

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