FWIW I have never had good results trying to calculate the difference in
resonant freq from low heights vs the desired height on an inverted V.
I finally reached the conclusion it was a waste of time to try and calculate
the difference.
Hoist the center up to its final height and leave a generous amount on the ends
and lower and raise each of the ends and keep pruning till you get nirvana.
Bob
K6UJ
Onp 4, 2013, at 5:42 PM, Wes Attaway (N5WA) wrote:
> Why not use EZNEC or similar program to model the dipole at 8' straight
> across and then at the 65'apex with whatever the height of the ends are?
>
> This should give you a good idea of what to expect.
>
> You should be able to determine how to cut the dipole while it is at 8' so
> that it will be close to what you want when you raise the apex.
>
>
> ----------------- Wes Attaway (N5WA) -------------------
> 1138 Waters Edge Circle, Shreveport, LA 71106
> 318-797-4972 (Office) - 318-393-3289 (Cell)
> Computer Consulting and Forensics
> -------------- EnCase Certified Examiner ---------------
>
>
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of
> john@kk9a.com
> Sent: Wednesday, September 04, 2013 7:35 PM
> To: TOWERTALK@contesting.com
> Subject: Re: [TowerTalk] Cutting a dipole
>
> The resonant frequency and the impedance will go up if it remained a
> straight dipole. Tuning it at 8 feet high is a waste of time.
>
> John KK9A
>
>
> To:<towertalk@contesting.com>
> Subject:[TowerTalk] Cutting a dipole
> From:"James Setzler" <jms_k1sd@verizon.net>
> Date:Wed, 04 Sep 2013 18:32:38 -0400
> List-post:<towertalk@contesting.com">mailto:towertalk@contesting.com>
>
> Greetings
>
>
>
> I should know this but I've not made too many dipoles.
>
>
>
> While it is hanging at 8 feet so I can get to it, I've cut a 40 m dipole to
> the frequency I want. When I raise the apex to 65 feet as an inverted V,
> how will the resonance frequency change?
>
>
>
> 73 James K1SD
>
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