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AO-7 Uplink Power - Please be careful!

Hello fellow AMSAT members:

OSCAR 7 is an amazing bird to work, because it is one of the oldest
operational satellites in Earth orbit (amateur or professional).  It's neat
to work such an historic satellite and I try to be on every AO-7 pass over
North America.  However, because it is running completely on the Solar
Panels, it's easy to overdrive the input.  When this happens, it takes down
the transponder for any other users on the Pass Band (and I understand it
could even damage the bird).  

The bird's sensitivity can vary widely during each pass.  I found that I
too, have been "guilty" of hitting the bird too hard in the past -- and
nowadays I "ride" my power output / mike gain throughout each AO-7 pass
(with the goal of never using any more power than is absolutely necessary at
any point in the pass).  

A good way to know if you're hitting the bird with too much power, is the
sound of the frequency "warbling" (i.e., FM'ing - which is noticeable on
both CW and SSB transmissions).  If you hear your signal FM'ing, you are
hitting it with too much effective radiated power...

Lately, I've noticed an increasing amount of CW activity on AO-7, where the
input is so strong that all voice QSO's anywhere else on the transponder are
getting "wiped out" (you can actually hear the SSB transmissions shutting on
and off with each press of the CW key).  Folks, I know it's easy to loose
sight of the importance of keeping your power to a minimum when working
OSCAR 7 and I'm simply reminding all AO-7 users that it is important to
watch your uplink power (SSB and CW).  

AO-7 has been in space for nearly 30 years, let's take good care of this
grand old satellite.  Thanks a lot and I hope to work you on OSCAR 7 - the
amazing OPERATIONAL piece of AMSAT history!  

73 from Chuck

KE6OAG in CM97

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