[amsat-bb] Az-El Rotors

[Edward R Cole]

I agree with JoAnne:

Put up a small yagi fixed in elevation at 15-30 degrees with a cheap 
antenna rotator for azimuth (Alliance HD73 or similar) and you will 
be in business without the $700 cost of az-el.  Even mounting an 
Arrow this way is good to have hands-free operation.

I built a pair of Lindenblad antennas, which was an interesting 
project, and they worked OK.  But I missed having the gain of a yagi 
system for stronger reception of the sats (my old system was rated 
for AO-40).  I have taken down my Lindenblads.

I've acquired a replacement controller for my Yaesu B5400 and will 
re-install part of (26-elements) of my M2 436CP42 and have a 
7-element M2 2m yagi on a short tower with the B5400.  Probably will 
not get to this until spring.  You can see what I have done here:
http://www.kl7uw.com/sat.htm

73, Ed - KL7UW

From: "JoAnne Maenpaa" <k9jkm at comcast.net>
To: "'AMSAT bbs'" <amsat-bb at amsat.org>
Subject: Re: [amsat-bb] Az-El Rotors
Message-ID: <000901d15778$4c73e210$e55ba630$@net>
Content-Type: text/plain;       charset="utf-8"

Hi Fred,

 > ... starting with a small single antenna with both 2m and 70cm on
 > it (i.e. Arrow or other) ...

I've found that an azimuth-only rotor with a fixed elevation of 20? 
or so works well enough for most of what I do with LEO satellites. I 
got my rotor from ebay for $20. It is a primitive setup - manual 
tracking. Much of the time I prefer using an Arrow antenna.

If you are looking for rotor projects there have been two designs 
published over the past year or so in the AMSAT Journal. Here is some 
information you can use to find out more about these:

The AMSAT store has the printed circuit board for WA8SME's WRAPS 
inexpensive, portable az-el rotor system. See http://store.amsat.org 
and look for the "WRAPS Tracker Circuit Board". There is also a link 
to the article by Mark, WA8SME.

Bob, KI4SBL, wrote an article about his homebrew az-el rotor system, 
"CNCTRK ? A LinuxCNC Based Satellite Tracking System", for the AMSAT 
Journal. Bob has details of this project and the parts he sells along 
with a PDF of the article posted on his web site: 
http://ki4sbl.dodropin.org/CNCTRK/

--
73 de JoAnne K9JKM
k9jkm at amsat.org


73, Ed - KL7UW
http://www.kl7uw.com
     "Kits made by KL7UW"
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