[amsat-bb] Re: Polarization for ISS and Weather Satellites

[Grant Zehr]

The polar orbiting NOAA weather satellites have right hand circular helical
antennas for the VHF APT service.  Right hand circular polarization is
recommended for NOAA APT receiving antennas.

http://www.noaasis.noaa.gov/NOAASIS/pubs/Users_Guide-Building_Receive_Statio
ns_March_2009.pdf

See the section on ground station antennas, p. 45

Grant Zehr AA9LC

-----Original Message-----
From: amsat-bb-bounces at amsat.org [mailto:amsat-bb-bounces at amsat.org] On
Behalf Of Graham Dillabough
Sent: Saturday, October 27, 2012 3:58 PM
To: amsat-bb at amsat.org
Subject: [amsat-bb] Polarization for ISS and Weather Satellites

I haven't posted here in a very long time.  I hope this works.

I am building two Quadrifilar Helix antennas (from QST, August 1996); 
one for weather satellite experimentation, and one as a backup 
antenna for an upcoming ARISS contact.

I haven't found anything in the ARRL antenna book, or on the web, 
that specifically says that one mode (RHCP or LHCP) of circular 
polarization is better than the other for either of the two 
applications noted above.

Any insight or experience with polarization issues with the ISS and 
weather satellites are appreciated.  The last time I did an ARISS 
contact, I was plagued with very deep fades, and want to do better this
time.

Thanks,
Graham

Graham Dillabough, VE6KJ, VO1DZA

Albert Einstein, when asked to describe radio, replied:

"You see, wire telegraph is a kind of a very, very long cat. You pull his
tail in New York and his head is meowing in Los Angeles. Do you understand
this? And radio operates exactly the same way: you send signals here, they
receive them there. The only difference is that there is no cat."
Albert Einstein (1879-1955) 

_______________________________________________
Sent via AMSAT-BB at 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