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Re: Saying "hi" on AO27 gets my goat!



   I think the 22C has a claimed 15 dBdi gain figure.  A pair of them
   properly power divided should show an 18 dBdi gain figure.  If you
   figure a 1.5 dB loss in your coax, with a 160 watt PEP output, your EIRP
   will be somewhere around 38.5 dBW, and your ERP should be a whopping
   7,147 watts ERP! Be careful with that power; you might just go down in
   history as the Farthest West Ham in West Texas to start a grass fire,
   with his ham station!

Hey, i've been running 1W lately into homebrew 4 element-pair LPVA most of
the time lately, and on today's Pacific pass, getting decent signal reports
on a couple hundred milliwatts.  It's a little harder to get over the way-
south-of-the-border QRM, though, at that power level.

   Nah.  Good-old-boy network?  I don't think one exists in the context you
   claim.  Most of the big stations leave gaps in there for the smaller
   stations.  I can see why an operator frustrated by inability to get into
   the bird might arrive by that rationale.  I used to try working AO27
   with a Ringo antenna, and I imagine a JPole is at least as ineffective.

Well, out west at least, most of the experienced operators seem to be
running Arrow antennas or something comparable.  I'm pleased to give them
57 signal reports, because that means they're running just enough power to
communicate effectively.

   The midcontinent passes do get crazy as the pass proceeds on weekends to the
   point where it can become unusable.  I got into AO27 a few times today very 
   easily but as the pass progressed, hardly anyone was getting any intelligible 
   exchanges through the QRM.  I did hear Mike a few times from Sanibel Island 
   though :-).

You're right.  It's not so much of a problem with weekend passes as much as
DX passes over the 'States, with weekend DX passes being the worst.  People
try to be courteous, but the bird is just plain overloaded.

    The key word is "PREAMP",  that is the best $100 (for a brand new one) or
    $50 or so (for a used one) that a guy could spend!

Not necessarily.  I think the real trick is get to an antenna with the
right pattern.  For my first year, i worked AO-27 with an FT-5100 with
no pre-amp and a 2m quarterwave on the rain gutter of my van, tuned for
decent SWR at 2m and 70cm.  It doesn't work that well for terrestrial
use at 70cm, 'cause most of the signal goes skyward, but that's exactly
what you want for AO-27.  I hated the overhead fades and didn't do so
well after that, but the point is that you don't neeed expensive gear.
That's one of the charms of AO-27 is that skill and cleverness is worth 
more than power.  The materials cost of my current antenna is about $10.
Maybe i'll write it up when there are more J-FM birds aloft, hopefully
next month!
                                -- KD6PAG
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