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PCsat Healthy!



PCsat seems in Excellent health.  But it depends on You.

PCsat spends more than half its life in DEEP DISCHARGE cycles from which
it cannot recover until it gets full Sun for a few orbits and can be
commanded (and remember) to keep its spare RX and TX's off.  PCsat was
in full Sun for 2 weeks over the holidays and although it is back to
maximum (35%) eclipses on every orbit now, she appears to be in good
health.

Several things are going on:
1) She is now back in MAX (35%) eclipse season!  yet running strong.
2) As long as she doesnt reset, she rememebrs to keep spare loads OFF.
3) Northern Hemisphere (USA and Europe) passes are in mid afternoon
4) So USA/Europe ops are occurring with best solar panel towards sun
5) Night passes (USA/EUR) are after 2 AM so low use in dark when risky
6) If she resets, spare RX and TX come on and she dies till May

BUT!  What kills us every time is a prime-time EVENING European pass.  And
these are coming up in about 2 weeks or so.  THere is little difference
between USA and European ops, but there are just more of them that use
PCsat.

So, if we can get EVERYONE everywhere to only operate PCsat between the
hours of Sunrise and Sunset in their area, then PCsat should operate
indefinately.  But all it takes is several packets in a row in the dark to
cause a dip in bus voltage and a reset and all is lost till MAY.
PCsat has no computer or controller on board.  Just a TNC in a box, so
we cannot schedule her for the 14 day/dark schedules per day...

Two rules will keep us out of trouble:
1) No operation at night after 1 hour past sunset and before sunrise
2) No unattended operations. (dont waste power if you are not there)

This will help avoid a crash due to high loads in the dark and loss of the
bird till May.

Thanks
Bob, WB4APR
US Naval Academy Satellite Lab

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