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Listen to AO-51 in L/S with your 2M handheld

Since AO-51 will be in L/S for a while, take the opportunity to put together 
a simple, portable
system to listen to S band on your 2M handheld.

I set the freq step size for the TH-D7A to 5 kHz and did quite a bit of 
Doppler correction
(from 145.250 to 145.140MHz), but listened to the last pass start to finish.

Using only my TH-D7A (in the left had), a K5GNA downconverter with a patch 
antenna connected
to it (in the right hand) was all I needed. I did run an extension cord out 
in the backyard to power the downconverter, but could convert this to 
battery power.  I image that one of K5OE's simple helix feeds
would work also. http://members.aol.com/k5oe/  you should be able to 
assemble one of these in about half an hour using available materials. 
Jerry also has a patch antenna design, that shouldn't be too time consuming.

Signals were excellent.  Take a few minutes and see how well you can copy 
AO-51 and the S-band downlink
on this very portable station.

I talked with Graham Shirville, G3VZV at the Symposium about this.  He made 
a post a few months ago about using this approach and I tried to duplicate 
it, but not sucessfully. He reaffirmed that it worked very well, so with a 
renewed interest I tried again.  I think the trick is to find the signal 
with its fast Doppler movement.
The feed is so wide that generally pointing in the right quadrant of the sky 
will work, but the signal doesn't stay on one frequency very long.  So, my 
advice is to hold the antenna steady and rotate your receiver freq knob 
looking for a signal. I got a full scale reading once I found it.

Give it a try,
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
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