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Re: [TowerTalk] CushCraft R7 Antenna Problem

To: towertalk@contesting.com
Subject: Re: [TowerTalk] CushCraft R7 Antenna Problem
From: Jeff Carter <towertalk@hidden-valley.com>
Reply-to: towertalk@hidden-valley.com
Date: Fri, 4 Sep 2009 16:46:45 -0400
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
I concur with this.  I've drained water out of a lot of those traps
over the years, and in some cases nobody would have thought it was
full of water.

Jeff/KD4RBG

On 9/4/09, Joe Subich, W4TV <lists@subich.com> wrote:
>
>  > Any ideas or suggests as to how to track down the problem?
>  > Sometime today or tmw, I will look inside the matching box to
>  > see what I can find. But if anyone as any experience or
>  > suggests, please let me know.
>
>
> Check the dielectric in the 20 and 30 meter traps capacitors -
>    http://www.telusplanet.net/public/telwest/R7/cushcraft_trap.htm
>    http://www.iol.ie/~bravo/r7_vertical.htm
>
>  If SWR is correct on 20 meters and up, it would indicate
>  the most likely fault is the 30 meter trap - either the
>  capacitor dielectric or the coil.
>
>  73,
>
>
>    ... Joe, W4TV
>
>
>
>
>
>  > -----Original Message-----
>  > From: towertalk-bounces@contesting.com
>  > [mailto:towertalk-bounces@contesting.com] On Behalf Of Ray
>  > Sent: Friday, September 04, 2009 12:42 PM
>  > To: towertalk@contesting.com
>  > Subject: [TowerTalk] CushCraft R7 Antenna Problem
>  >
>  >
>  > Recently I tried running about 600 - 700 watts to my old
>  > reliable Cushcraft R7 vertical. Everything went fine on 20m,
>  > but when I went to 40m the SWR became erratic, then jump to a
>  > very high level and stayed there (more than 6
>  > - 8:1). The RX is also quite numb on 40m. The same high SWR
>  > is on 30m too. 20m is still has a good low SWR.
>  >
>  >
>  >
>  > It seems that there is an open or something bad at the 30m
>  > joint or coil, but a visual inspection and ohm meter check
>  > show every think OK. I have not yet opened the matching box
>  > at the base. I did remove the heat shrink at the 30m coil
>  > connects, but those connects are fine with no burn spots
>  > along the coil.
>  >
>  >
>  >
>  > Any ideas or suggests as to how to track down the problem?
>  > Sometime today or tmw, I will look inside the matching box to
>  > see what I can find. But if anyone as any experience or
>  > suggests, please let me know.
>  >
>  >
>  >
>  > Ray, N6VR
>  >
>  > _______________________________________________
>  >
>
>
>
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