Pat:
I just checked the SWR on my 160M shunt-fed tower from the shack and it's
2:1 or lower from 1.8 - 1.9+ MHz. I don't ask questions.
73 de
Gene Smar AD3F
>
> I now have 30 radials installed on my tower and am shunt-feeding it through
> new
> coax, an antenna switch, and a vacuum variable. The coax run is 30ft. The
> tower is a 55ft crank-up with 20 ft of mast out the top and a TH7 at 56ft and
> a
> XM240 at 69ft. The shunt wire is 30 inches away from the tower and is #6
> stranded. I am able to get 1:1 on both 80M and 160M with my motor driven
> variable in a Gamma match configuration.
>
> The 1:1 reading is absolutely flat for about 60-70Khz. It is the same on
> both
> bands in as far as being flat and wide. I thought I might have a poor
> ground,
> but I have double checked all connections and resoldered everything that
> looks
> even remotely bad. I also have 15 ground rods connected to the tower on
> three
> legs besides the radials. This is my first attempt at shunt feeding a tower
> and
> my question is if it is possible to have such a flat SWR on a shunt fed
> tower?
> My numbers are with the MFJ are:
> 1830Khz R=24 X=167 SWR>25 397pf on the vacuum variable for a
> 1:1 reading
>
> 3500Khz R=24 X=295 SWR>25 157pf on the vacuum variable for a 1:1 reading
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather
> Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
> and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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