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RE: Newbie questions

I do not yet have a ham license but I have listened to satalites in your
area. You are facing a problem that I am currently working on. I decided to
make my own AZ-EL controller for tracking the satalites, and have decided to
use TV rotators for the axis control. I decided on replacing the AC motors
with small DC motors because that will make it easier for me to controll
them. In my searches on the internet I have found a site that explaines a
control circut that could be used to control your TV rotators. The site
location is http://www.ai.uga.edu/~mc/alcor.html. I hope this helps you and
if you have any more questions or need help with the microcontrollers I
would be willing to help you.


-----Original Message-----
From: owner-AMSAT-BB@AMSAT.Org [mailto:owner-AMSAT-BB@AMSAT.Org]On
Behalf Of David Beach
Sent: Sunday, December 08, 2002 1:35 PM
To: amsat-bb@AMSAT.Org
Subject: [amsat-bb] Newbie questions

I am new to satellites - so new in fact I haven't done anything! My
questions stem from the fact that an elderly ham friend (VE3GTF) is
'retiring' from
the satellite end of ham radio. He has generously offered me all his
equipment (minus
the transceivers) if I take it away when the snow goes away. He has been
inactive on satellites since approx the mid-90's - after the demise of
AO-13, I think.

I hope this is the correct forum for these questions. If you think the
answers will unnecessarily load up the mailboxes (and these questions are
likely old hat to experienced operators), reply directly to me.

The equipment is:

-one az-el setup with a 2m beam (Telex/hy-gain 216S) and a 70 cm beam
(Telex/hy-gain 215S)
-another az-el setup with two 2.4 GHz ring beams (Downeast MW 1245LY) and a
(Myers SB-32 - looks to me like something one might make from a BBQ grill!!)
-both az-el setups are TV rotator jobs, one using two Alliance U-110's and
other using an Alliance U-100 for elevation and a ChannelMaster (model
unknown) for azimuth. All are run from standard rotator controls with the az
and el directions marked on.
-a 100W 70cm power amp
-an assortment of preamps, downconverters and transverters to be able to
transmit on 440 and receive on 2M and 2.4G using his two HF rigs (using 10M)
-plus he was kind enough to supply lots of documentation along with a
frequency counter, GHz wattmeter and other assorted bits and pieces,
including the Satellite Experimenters' Handbook.

Christmas came early even though I won't get the antennas up before spring!


Backyard limitations (ahem, my wife is less enthusiastic about satellites
than I!) may keep me at one 'tower' rather than two. It seems to me that
three 2.4G antennas
is a lot!
Could the ring beams be put on the other setup?
Is the 'BBQ grill' parabolic antenna better/worse than two ring beams?
Satellites seem to come and go - what are the 'priority bands' if I have to
stick with what I can get on a single az-el setup?

He was using manual antenna rotating. Today, computers are cheap - I have a
couple of spares!
How hard is it to computer control the old (kerchunk, kerchunk!) TV-type
of the sort I mentioned? I am fine at construction and could assemble a
controller if I had plans or a kit. I don't feel like designing one! I want
to get started relatively inexpensively and can't just go out and buy a
Yaesu 5500 (or whatever)!
Do I *need* to computer control these antennas? Manual control would be
simple BUT (never having operated satellites) it looks like running the
rotators while operating would be a handful!
Comments? Suggestions?

I have lots of other questions - and more, I am sure, will arise later. I
don't know of any active satellite users in my area (Prince Edward County,
Ontario, for any VE3's who are reading this) but will start asking around to
see if I can find a local Elmer.

Thanks for your help.

David Beach

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