This may have been discussed before forgive me if it has I am new at this.
I was wondering if an Elk or Arrow antenna mounted on a mast at an angle with a TV rotor would work as a base antenna for Satellite work. Has anyone done this and any tips on how you have been successful. If this does not work what would be the best antenna other than beams for under $200.00 to do this? Thanks for your information.
It's been done a number of times, though like most things, it's a compromise that will work better for some satellites than others.
The thing about the Elk or Arrow that works well with their usual (hand-held) use is that they are linearly polarized, but mounted on a 3-axis rotor system (your wrist) which can compensate for Azimuth, Elevation, and also rotate to match the polarization of a linearly polarized satellite. Many satellites are linear right now, so a fixed mounting will mean you will get some deep fading as the satellite spins. It's not unworkable - I have an Az / El rotor system with a vertically polarized 2m beam (not an Arrow), and I've learned to adapt.
The fixed Elevation is actually less of an issue. Put it at about 20 degrees up, and you should be good to go. Satellites spend most of their time NOT being directly overhead, and those antennas are not so sharp in their reception pattern anyway. And when the satellite is overhead it's also a lot closer, so that compensates a bit.
The last tip is that I don't think either antenna were designed for extended outdoor use, so they may deteriorate faster than otherwise, depending on your particular weather patterns.
But, as with most thing in this hobby, give it a try. The worst thing that will happen is that you will learn something.
Greg KO6TH
ld.lucas@frontier.com wrote:
This may have been discussed before forgive me if it has I am new at this.
I was wondering if an Elk or Arrow antenna mounted on a mast at an angle with a TV rotor would work as a base antenna for Satellite work. Has anyone done this and any tips on how you have been successful. If this does not work what would be the best antenna other than beams for under $200.00 to do this? Thanks for your information.
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Id, I have sent you my informal 'construction article' along with pictures direct.
This is an excellent compromise and economical...and it works great. I use the Elk because, as you will see in the photos, you can center the weight mass right over the RS rotor. I don't see how you could do that with an Arrow, so I think the Arrow will be way too much weight hanging out there. As you will see in the photos, you can paint ( any solid non-metallic color) all the pvc pieces for weather an uv protection. The antenna and rotor can be protected with multiple coasts of Rustoleum claer
Also, I think Bob Brunniga (from this group) has documented that 15 deg fixed is the best overall el setting. You can also modify my design to have the preamp on top. (mine is in the shack)
This setup got me most of my VUCC (but so did AO-51 !!) and it works.
GL, Ted, K7TRK
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of ld.lucas@frontier.com Sent: Sunday, August 19, 2012 2:18 AM To: amsat-bb@amsat.org Subject: [amsat-bb] Antenna
This may have been discussed before forgive me if it has I am new at this.
I was wondering if an Elk or Arrow antenna mounted on a mast at an angle with a TV rotor would work as a base antenna for Satellite work. Has anyone done this and any tips on how you have been successful. If this does not work what would be the best antenna other than beams for under $200.00 to do this? Thanks for your information.
_______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Also, I think Bob Brunniga... has documented that 15 deg fixed is the best overall el setting.
Yep, that puts the main beam on the horizon where you need it most and where satellties spend over 70% of their time. Even at 15 degrees, you still are within 1 dB of max gain on the horizon. That same amount of gain covers up to 30 degree too. And anything above 30 degrees is 6 to 10 dB CLOSER and does not need much gain. Above 70 degres there begins to be a null, but satellites will be in that null less than 1% of the overall contact time.
Bob, WB4APR
participants (4)
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Bob Bruninga -
Greg D -
ld.lucas＠frontier.com -
Ted