> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Tom Rauch
> Sent: Monday, October 17, 2005 9:15 AM
> To: Dale L Martin; towertalk@contesting.com
> Subject: Re: [TowerTalk] Dipole resonates lower than expected.
>
> > All the responses have addressed the effects of insulation
> on the
> > wire, Bob. But, no one has commented on what the analyzer
> result was
> > in a 75 ohm system. Does your analyzer evaluate 75 ohm
> systems or
> > 52/50 ohm systems?
>
> That doesn't matter Dale. He is reading R and X on the
> analyzer, not SWR.
>
> What you say about tuning the combined system does matter.
>
> If the feedline has standing waves the only time an analyzer
> inside the house will directly indicate actual antenna
> resonance is when the feedline is an exact multiple of 1/4
> wl long. If the feeder is not an exact multiple of 1/4 wl
> and has standing waves, it will cause the X=0 point to shift
> frequency from the value at the antenna.
>
> I'd bet not many people consider that fact when setting
> resonance.
>
> 73 Tom
>
Wouldn't that be exact 1/2 wavelength of feed line or multiples, and not 1/4
wavelength.
73
Gary K4FMX
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