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Re: [TowerTalk] Shunt Feeding, Can this be?

To: <towertalk@contesting.com>
Subject: Re: [TowerTalk] Shunt Feeding, Can this be?
From: "Pat Chiles" <chilesp@adelphia.net>
Date: Tue, 15 Nov 2005 17:55:32 -0500
List-post: <mailto:towertalk@contesting.com>
Gene, you obviously do not have my black cloud.  My surprise is more a 
result of it working on the first try than anything else.  This can't be! 
Was my original reaction.  I will accept you suggestion because it makes 
sense and is going to save me putting up another 160m antenna to make 
comparisons with.

Bill,  I don't have a 1000 watts for 160M.  Just 100 watts for . First the 
antenna then the amplifier.  I did put 400 watts into it on 80M with my 
SB220 and a G3 told me that my signal was "crushing".  Once again, I knew he 
couldn't be talking about my signal because of my black cloud so I went 
looking for a problem.

Thanks for the responses.  I will just enjoy it and not ask questions.

Pat, K8PC
----- Original Message ----- 
From: <ersmar@comcast.net>
To: "Pat Chiles" <chilesp@adelphia.net>; <towertalk@contesting.com>
Sent: Tuesday, November 15, 2005 4:13 PM
Subject: Re: [TowerTalk] Shunt Feeding, Can this be?


> 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.
>
> _______________________________________________
> 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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