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Re: Finally Heard It! AO-27



   I know it may not seem like much to some of you but I was able to hear the 
   downlink for the first time today here in Morgantown,WV (FM09) but was barely 
   able to make out what was being said. Was only using a small gain 2/70 mobile 
   whip on the mini-van and no pre-amp.

That's right, except possibly on low elevation passes, gain omni antennas 
are almost useless for satellite work.  They get their gain by concentrating
energy to/from the horizon.

   Was able to make out someone talking about something about around or up the 
   river, or something like that?

   Things learned: MUST HAVE PREAMP, MUST HAVE PREAMP, MUST HAVE PREAMP!!!  Was
   using a Motorola mobile radio programmed for the 5 channel rx system and wa 
   only able to understand what was being said when it was on ch.3 only? nothing 
   readable on 1,2,4,5. Also, could use some warmer weather too...

Actually, you just need sensitive receiver, one way or another, as AO-27
puts out about 1/2 W under normal operation.  I worked AO-27 for close to
a year using just a 2 meter quarter-wave tuned for decent SWR at 70 cm
with a FT-5100 dual-band mobile rig.  That's not a very good antenna for
70cm repeater work, because most of the signal goes skywards.  But that's
just what one wants for AO-27:  to have some gain above the horizon and
not to hear quite so much terrestrial QRM.  But i had to get away from the
high RF urban environment for this to be more than a struggle at times,
and was able to work Vermont from California. This may not be very helpful
to you, Jacob, since you're using separate rigs for uplink and downlink,
but others might want to try this.  I've been meaning to try making an
70cm eggbeater for the roof of my van, but just haven't gotten around it.
I'll give a report if i come up with anything interesting.

   Well I finally feel like I can get this satellite stuff working after many 
   tries with no success. Hopefully will have the uplink setup for tommorrows 
   passes and the weekend.

I was frustrated for a couple of years by this, not knowing that my problem
was largely local QRM.  Once i identified the worst source of it, i was able
to park my van where it would null out the offending signal, and with that,
i was able to be successful.

Good luck, and i really hope to work you soon.  You'll probably end up
working me or the other John (K6YK) out here in California once you're 
up on AO-27.  We'll be listening for you.

                            -- KD6PAG  (Networking Old-Timer, satellite QRPer)
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