Q Chris Bloy wrote:
How strong would it be? Would you pick it up with a 3-ele yagi?
Hi All:
In theory you can work a satellite such as AO-10 (in a Molnyia Orbit) with a Zero Gain antenna system. You just need to be in the right place a the right time. The orbit for AO-10 varies in altitude from 2,560 Miles (4,120 km) to 21,747 Miles (35,000 km ) every day (twice a day).
If the low orbit Dip is close to your House then you will have a 15 –30 minute opening when a Zero Gain antenna system will work for a few minutes (assuming AO-10 is running that day). However as soon as the satellite starts to climb in altitude, you will need to switch over to a higher gain antennas such as a 9-12 dBd system.
In the spring of 1994 I worked AO-13 many times with a pair of Zero Gain Ringo vertical antennas mounted to my Apartment Deck (on a hill, with 200-watt amps). The Secret was timing. I would plan ahead and then wait for the low altitude dip to take place near my apartment in Boston and set aside that time to work people on AO-13. My window of access time was very limited to approximately 15-30 minutes of good access, before the satellite screamed up to higher altitude.
After my new house and tower were installed, I switched over to a full AZ/EL antenna system (22 elements CP on 2 meters (element gain ~10 dBd) and 40 elements (element gain ~14 dBd) on 440 CP, Amps and LMR-600). At the higher altitude’s 21,747 Miles (35,000 km ) I could still work AO-13, however AO-10 was much more difficult.
This Month March 2009 AO-10’s Low dip is in the South Pacific and in the South Indian oceans. Has anyone heard AO-10 recently? I would like to give it a try again.
73 Miles WF1F Marexmg.org
Note: I prefer to use the terms Element gain because it cuts out the Advertisement hype. Most advertisers add an extra 3-6 points of gain to an antenna. If you ever see an antenna advertised with two letters “dB”, always subtract 3+ to convert it to “dBd”. Or Just count how many Half-wave dipoles are in this antenna and use the chart.
Antenna power tips
http://www.marexmg.org/fileshtml/packetpower.html
--- On Sun, 3/8/09, Gordon JC Pearce gordonjcp@gjcp.net wrote:
From: Gordon JC Pearce gordonjcp@gjcp.net Subject: [amsat-bb] Re: AO-10 Report On Sat Status To: amsat-bb@amsat.org Date: Sunday, March 8, 2009, 7:00 PM Chris Bloy wrote:
Hi All,
I see that IK2MKE has reported hearing AO-10, any idea
if this is
possible?
How strong would it be? Would you pick it up with a 3-ele yagi?
I could hear *something* on 145.810MHz but I'm in the middle of a city so it could be just about anything. I'll try in an hour to see if I can rule out local QRM.
Gordon _______________________________________________ Sent via AMSAT-BB@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