Hi Ken...
Of course there are advantages to az/el tracking. With "spot on" TRACKING you will have better signal levels to work with on receive and be able to use less power on transmit.
The disadvantages of az/el are that you do need ACCURATE TRACKING or you can possibly worsen your received signal strength from the Sats. ISS is especially a challenge as it is so close to the Earth's surface (~200) miles that it's passes can move across your visible sky really quickly.
Your initial inquiry included a "hands off" requirement. That means tracking software that controls the rotors automatically. While you are at it you might as well adjust for doppler. Not much on 2 meters but enough, and a requirement on 435.
So...your decision becomes...do you stop operating as you collect this gear,software and fund this transition, or do you take the next step up and set up an AZ rotor while you are contemplating the rest. How much time do you have to accomplish this setup? How much money? What type of antennas are you considering? Circular polarization? Antenna gain vs required accuracy?
You have mentioned ISS several times...it can be worked with a HT and a rubber duck...at least on a clear pass. It has been shown many times that one of the best antennas for ISS is a 19" whip over a good groundplane. The same antenna works on 435 also.
Your available time and money should help set your goals for your antenna system and reap the rewards you are satisfied with.
Me...I'm a minimalist ;-)
Roger WA1KAT
----- Original Message ----- From: "Ken Owen" n6kth@n6kth.com To: amsat-bb@amsat.org Sent: Saturday, January 05, 2008 11:20 AM Subject: [amsat-bb] Re: Antenna advice
Hi folks:
So, I understand those that say it's not worth "chasing the last 2
percent"
with an elevation rotor. Is there ANY advantage to having EL capability
for
satellite purposes? What about for working the ISS?
Thanks,
Ken, N6KTH
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