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Field Day on AO-40 from N7UW

I dragged out my junk for the N7UW (Univ of Wyoming's ARC) Field Day effort.
Had great fun making 14 contacts (12 voice, 2 CW).  Not a big number, but 
still fun, contacting stations on both coasts and both borders of the US.
These were my (and the club's) first successful QSOs on AO-40.

Rig: FT-736R
Uplink: 100 brick amp on 440 into a home-brew 15-element Quagi.
Downlink: AA2TX-design aluminum foil pyramidal horn into a DEM preamp into 
a lightly-modified Drake 2880.
Location: DN61 in the Snowy Range mountains of southeast Wyoming.

This setup got me a beacon of about S5 at best.

Activity was brisk for the first few hours of Field Day, but by 19:00-ish 
UTC I was finding fewer and fewer stations.  Well before the satellite set 
for me (around 21:30 UTC) I could still hear myself in the downlink clearly 
but could find no other stations.  What was up with that?

Sunday the beacon was about S4 at best, but my signal coming back down was 
much weaker.  I could hear my voice signal in there, but would not consider 
it copyable.  I roped a good CW op (my CW skills are shameful) to make two 
contacts on Sunday, but could not find much other copyable activity.  High 
squint maybe?  Don't know what the squint was at any time during FD.

The two antennas were separately aimed (no fancy two-antenna mount readily 
available).  For the horn I simply shimmed the front edge with 2x4s as 
necessary for elevation (with a 1x2 for "fine tuning"), and spun the horn 
and/or table it was on for azimuth.  For high elevations I dropped one set 
of legs on the folding table which gave me about 35 degrees up, requiring 
fewer shims.

For the uplink, I used a Radio Shack tripod and mast.  I simply spun the 
mast for azimuth, and built the Quagi with a pivot for elevation, using a 
c-clamp to lock in place.  More on this antenna in another post.

David, ky7dr

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