Hi Wes,
The issue here is that he is not over resonant radials and a balun which
would likely call for what you suggest.
He's over an FCP roughly 130 ohms capacitive reactance and a true
transformer which has normal residual inductance. Horizontal plus vertical
from 140' to 155' is common for L/FCP cut for R=50 and X=whatever often
corrected by a series cap. This extra length has the performance advantage
of improving RF current density up high on the vertical wire.
When an L and counterpoise are very efficient the ground
characteristics and surroundings can "pull" the particulars. That is why
the sweet length is a range instead of a singular value.
73, Guy K2AV
On Monday, November 7, 2016, Wes Attaway (N5WA) <wesattaway@bellsouth.net>
wrote:
> I haven't run any numbers but it seems like you should just shorten the
> horizontal wire (resonance freq is too low). I would go back to about 65'
> horizontal. Somewhere in the range of 60' to 70' you should get close
> enough.
>
> -------------------
> Wes Attaway (N5WA)
> (318) 393-3289 - Shreveport, LA
> Computer/Cellphone Forensics
> AttawayForensics.com
> -------------------
>
> -----Original Message-----
> From: Topband [mailto:topband-bounces@contesting.com <javascript:;>] On
> Behalf Of Art Heft
> Sent: Monday, November 07, 2016 3:06 PM
> To: topband@contesting.com <javascript:;>
> Subject: Topband: 160 m inverted L
>
> I finally got the inverted L up this afternoon. Vertical dimension is 65'
> and the almost horizontal dimension is 95'. I am using a very carefully
> built FCP and the commercial transformer. My SARK 110 shows resonance at
> about 1.68 MHz but the resistive part is up around 1000 ohms. Taken right
> at the antenna. Doesn't seem right to me. Any ideas?
> 73, Art K8CIT Hillman MI
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
> _________________
> Topband Reflector Archives - http://www.contesting.com/_topband
>
--
Sent via Gmail Mobile on my iPhone
_________________
Topband Reflector Archives - http://www.contesting.com/_topband
|