Dear All,
Currently for my satellite station I am using double stacked vertical polarized yagi antennas for 2M and 70 CM.
However, due to mounting constrains, I would like to mount them in a H configuration instead, on the G-5500 rotator, with the 2M antenna on one side and the 70 cm antenna on the other. A yagi for L and S band will be mounted in between the two antennas on the horizontal boom.
This would mean that I will require the antenna to be horizontally polarized instead of vertically polarized unless I use a non-metallic boom. Before I perform this, I would like to know what are the differences with using horizontal instead of vertical polarization when operation the LEOs such as AO-51, SO-50 and etc. Also, what are the effects of using a horizontal polarization with the ISS on 2M?
Sorry if this has been asked before, but was just trying to be sure before I perform any major modifications. Thank you very much in advance.
73, Sion Chow Q. C., 9W2QC.
Sion,
I have been using horiz oriented yagis on the LEOS for 5 months now.. and I am VERY pleased with their capabilities. My station is almost exactly as yours. Visit my web page and you can see the set up yourself.
Make sure you check my log as well to give you an idea of effectiveness.
-Steve Raas N2JDQ
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Sion Chow Q. C. (9W2QC) Sent: Friday, May 25, 2007 11:05 AM To: [email protected] Subject: [amsat-bb] Horizontal Polarized Antenna
Dear All,
Currently for my satellite station I am using double stacked vertical polarized yagi antennas for 2M and 70 CM.
However, due to mounting constrains, I would like to mount them in a H configuration instead, on the G-5500 rotator, with the 2M antenna on one side and the 70 cm antenna on the other. A yagi for L and S band will be mounted in between the two antennas on the horizontal boom.
This would mean that I will require the antenna to be horizontally polarized instead of vertically polarized unless I use a non-metallic boom. Before I perform this, I would like to know what are the differences with using horizontal instead of vertical polarization when operation the LEOs such as AO-51, SO-50 and etc. Also, what are the effects of using a horizontal polarization with the ISS on 2M?
Sorry if this has been asked before, but was just trying to be sure before I perform any major modifications. Thank you very much in advance.
73, Sion Chow Q. C., 9W2QC.
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if you're using single plane polarization yagis for the sats it doesn't matter what that polarization is ssince the satellites are not fixed in their polarization themselves often the satellites are rotating even so there will be no change in effect if you decide to do horizontal or vertical. Most satellite work is done with circular polarization because it receives equally well no matter the polarization so the satellite won't fade at all if it rotates. if you have a copy of the ARRL handbook the space communications chapter would be a good thing for you to read...although it is a little bit outdated -Steve VA3SAX
if you're using single plane polarization yagis for the sats it doesn't matter what that polarization is ssince the satellites are not fixed...
But some satellites are magnetic stabilized to the earth's magnetic field and so these satellites are horizontally polarized nearer the equator and vertically polarized near the poles. And very predictible in between.
On the RAFT re-entry web page are two horizon views of these changes in polarization for such spcecraft. The two views are about 30% down the page:
http://www.ew.usna.edu/~bruninga/craft/save-raft.html
A correllary to this is that when these satellites are due south of you (in the N hemisphere) the antenna is pointed right at you, so you are in a null and signals are weak for a while...
Bob, WB4APR
--- Robert Bruninga [email protected] wrote:
But some satellites are magnetic stabilized to the earth's magnetic field and so these satellites are horizontally polarized nearer the equator and vertically polarized near the poles.
...even if the Satellite has Circular polarization?
Or you are talking in case that the Satellite has Linear pol. antenna?
73, Mak SV1BSX
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Robert Bruninga -
Sion Chow Q. C. (9W2QC) -
Steve Attfield -
Steve Raas -
SV1BSX