Larry,
I don't have a sceintific answer for you, just practical experience.
I have the rotor mounted sideways off to the side of the mast. So the
elements are out in the clear when in the vertical position. I'm sure the
mounting makes some difference. Just how much I don't know. I initially ran
some test with a friend about 50 miles away. We checked it out both
horizontal and Vertical. The signals were very close regardless of
orientation.
We also experienced some signal phasing occasionally and I was able to
optimize the signals by rotating the polarization on my antenna. I still use
the same antenna and it is mounted about 8ft above my TH6DXX, and I have a
tri-band J-pole above that, covering 144/220/440.
The rotor is an old CDE TV rotor, that I acquired at a swap fest without
controller. It initially had the contact for the ratchet type indicator. I
ripped all that out and installed two micro switches at O & 90 degree
points.
I have not applied this technology to my TH6DXX, but sure have thought about
it...(:->
* 73's Jim W5IFP *
>-----Original Message-----
>From: Larry Banks [mailto:larryb.w1dyj@verizon.net]
>Sent: Thursday, April 09, 2009 19:32
>To: Jim Hargrave; Towertalk
>Subject: Re: [TowerTalk] Antennas at 45° [was Gizmotchy's]
>
>
>Hi Jim,
>
>Good idea.
>
>One of the reasons I went with 45° is that I did not want the
>vertical mast
>to ruin the antenna pattern, which happens when the mast goes
>though the
>yagi, or even if the yagi is at the end of the mast. How did
>you prevent
>this problem?
>
>73,
>Larry
>W1DYJ
>
>
>----- Original Message -----
>From: "Jim Hargrave" <w5ifp@gvtc.com>
>To: "Towertalk" <towertalk@contesting.com>
>Sent: Thursday, April 09, 2009 3:18 PM
>Subject: Re: [TowerTalk] Gizmotchy's
>
>
>
>
> >-----Original Message-----
> >From: towertalk-bounces@contesting.com
> >[mailto:towertalk-bounces@contesting.com]On Behalf Of Larry Banks
> >Sent: Thursday, April 09, 2009 16:19
> >To: Dan Zimmerman N3OX; towertalk@contesting.com
> >Subject: Re: [TowerTalk] Gizmotchy's
> >
> >
> >Hi Dan,
> >
> >You said this far better that I did! Thanks for the better
>explanation.
> >
> >For the record, I used a 2M yagi at 45° for a few years to
>"optimize"
> >(compromise?) both SSB and FM. Worked. Turned out is was great for
> >directing Fox Hunts -- with the tricks the foxes did.
> >
> >73 -- Larry -- W1DYJ
>
>Larry,
>
>I have a better idea. I have a 14 element Hygain 2m beam. I
>installed a TV
>antenna rotor mounted horizontal at the midpoint of the Boom
>and rotate the
>beam vertical for FM and horizontal for SSB and anywhere in between for
>possible phasing. I modified the rotor and installed limit
>switches and do
>not use a control box. I just added a On/OFF/ON switch to the my main
>controller. It has operated great for the past 20 years.
>
> * 73's Jim W5IFP *
>
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