Regular users will have noted that the
AO-7 mode-B transponder has begun to "behave" again.
We're still not sure 'exactly' what happened, several "theories"
have been bandied about ... what is certain !!! is that it was a
power related problem so let us concentrate on *NOT* belting her
with excessive power.
When you can't hear yourself adequately ... IMPROVE YOUR RECEIVE
CAPABILITIES.
Cranking up your transmit power to compensate for an inadequate
receiving system is *NOT* the way to go. Remember ... AO-7 is
running at less than optimum in all 4 modes. Let's not
accelerate her second demise by screwing up the power budget
anymore than it already is.
Excessive power *WILL* shorten the satellite's life. If, through
lack of experience you don't understand why ... please take the
trouble to find out.
I read on the Internet yesterday one prominent satellite
operator, a PA station, list part of his equipment as 100w and 2
x 10 element beams. He specify whether this was 100w EIRP or
100w fed to the aerials ... I most certainly hope it was *NOT*
the latter since assuming a line loss of 3dB that would give an
EIRP of well over 500 watts with today's compact 10 element
beams ... enough to melt the plastic holding AO-7's solar panels
on the spaceframe.
(Yes, I'm kidding ... but 500w EIRP is 450 too many for AO-7).
Please remember, 31 years ago not all the "bits n' pieces" were
space-rated.
Three things you should improve for better AO-7 operating.
1) Receive capability.
2) Receive capability.
3) Receive capability.
At 06:27 UTC this morning I noticed something I havn't heard for
two years ... that which I presume was echos of the BMEWS radar,
I was rather "bemused" (pun intentional). It sounded like a
rapid machine-gun like auroral woodpecker ... or if you've never
experienced aurora propagation, like blowing through your nose
into the neck of a glass bottle ... "keying" it at about 65 wpm.
GM1SXX and myself suspected the Fyllingsdale BMEWS radar
situated on the north Yorkshire moors in the UK ...
BMEWS = ballistic missile early warning system.
For a detailed description see ...
<http://www.observations.biz/Joint_Observations/BMEWS_ed.htm>
73 John. <la2qaa@amsat.org>
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