Arrow Antenna 2m/440cm Element Orientation question?

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spdfile1

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I have an Arrow II Antenna used for satellite workings (Model 146/437-10WBP) that I will be using as a beam (or directional) antenna for my Kenwood Mobile radio in hopes of hitting fringe repeaters better. The antenna is mounted on a camera tripod and the current element orientation on the horizontal beam coming from the camera tripod is 2m elements are horizontal and 440cm elements are vertical. Someone told me that the 2m elements should be vertical. Does it really matter is my question. I plan on using it for both bands at different times.
 

Thunderknight

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For the most part, FM on 6m and above is vertical polarization. SSB, CW etc is horizontal.
If you use the 2m (or 440) elements to try to reach a repeater, they should be vertical.
 

crazyboy

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I thought this was a question on the tech exam? If you are only using it for FM repeater work, you should look into a different antenna that you can mount with both bands vertical.
 

AK9R

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Satellite VHF/UHF antennas are a bit of a problem when it comes to working terrestrial repeaters. Most FM repeaters from 10m on up use vertical antennas, so your antenna should be vertical to match. A horizontal antenna working a vertical antenna will have about 18dB of loss just due to the antenna orientation.

The problem you'll have with a satellite antenna is that if you orient it so the 2m elements are vertical, the 70cm elements will be horizontal and vice versa. A compromise would be orient to the antenna so that the elements are on a 45 degree angle.
 

SCPD

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A good question Spdfile... and one that can be an opening to some interesting experimentation.
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While the official word on ham V/UHF FM antennas is Vertical, the ability you have of altering the polarization is a great asset. Being able to swing the antenna about on its azimuth- even its elevation-- makes this even better.
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Many signals start off vertically polarized, but get reflected off objects or refracted thru the atmosphere- arriving at your antenna at anyone's- guess- polarization.
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Since you've the ability to change things, I'd start out vertical, and try rotating the beam once you've acquired the repeater. My guess is that you may find that not only will the signal not be the strictly vertical, but it may also peak considerably off to a side -- as it may be reflecting off some favorable object; resulting in a much better than the direct path.
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When you get the chance to track a satellite, this will become all too apparent-- the polarization is constantly changing, producing some really deep fades if you don't correct for it.
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.......Good luck- you have the basis for some first class antenna experiments...... :)
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......................CF
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spdfile1

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All good input so far. So I originally had my yagi mounted on my camera tripod along the top which made the uhf elements vertically correct. Now mind you my camera tripod has a feature where you can flip the top part where you hook the camera to up. So when I flipped it up to change the vhf elements to vertical the antenna would droop down because the camera tripod attachment wouldn't hold it. I ended up drilling a hole in the top part and resting the beam on a ledge of sorts on the top part of the tripod and then putting a screw threw the newly drilled hole and hole in the beam and got it to work both ways. Now I can have the UHF elements vertically correct in the regular position and once I flip it up I achieve success with having the VHF elements vertically correct.
 

SCPD

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~~~snip~~~.
Many signals start off vertically polarized, but get reflected off objects or refracted thru the atmosphere- arriving at your antenna at anyone's- guess- polarization.~~~snip~~~

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Exactly. Years ago I had a friend who lived about 12 miles away over difficult VHF terrain. We both had a vertical and a horizontal beam. Vertical to vertical didn't work. Horizontal to horizontal didn't work. But vertical to horizontal and horizontal to vertical did.
 
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