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Re: pt3 telemetry

 Jon Ogden writes:

> To me I think something else happened.  I still like the theory that it was
> some sort of solar particle(s) that caused all this to happen.  Let me
> speculate:
> A proton event occurred that overloaded the systems on the spacecraft.  This
> sort of overload/interference cause the IHUs to crash thereby taking the
> spacecraft off line.  Additionally, with the IHU in an unknown, random state
> various bogus commands could have been sent to different systems in the
> craft.  Perhaps the magnets or the momentum wheels were turned on and that
> increased the spin.  An electromagnetic event like this could damage sensors
> in a random fashion or it could "uncalibrate" them.  It could damage RF
> components, etc.

Or maybe it tried to "write" on lines that were just for "read" and damaged
some logic. Might have magnetorqued; might have spun one or more of the 
wheels too but, since they're supposed to be off, the telemetry doesn't 
pass on accurate figures.

Anyway, I *like* this theory. And, as I recall, there was a solar event a 
day or two before the burn. Food for thought.

> Lastly, I am bothered significantly by the two meter TX issue.  If it wasn't
> damaged then what would have kept it from turning on when the reset command
> was sent?

We don't know what bands they tried before they went to L band; and anyway
the "reset" should have brought up the (questionable) 70cm tx not the 2m one.
The 2m tx was transmitting at the time of the crash so it makes sense to me
to avoid as many common points as possible during the recovery. And DB2OS
just said that they'll try it again soon (once they've prepared for trouble).

Pity we can't "borrow" Maggies abandoned spy base; there'd be some neat
analysis equipment there.

Richard W L Limebear G3RWL
FOC # 1188

          So many beautiful girls ..... (sob) so little time
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