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Re: Antennas on the bird



Phil Karn wrote:

> Once again, the telemetry didn't just stop at some random time a day
> after the burn. There was "active work" going on in the propulsion
> system at the moment the 2m transmitter went off the air. Once again,
> that should be a clue.

I've been mulling that one. Our IPS friend MANY_ARMS was in play, as I recall.
The impression I gathered as to what that routine was to do was to open and
close a valve repeatedly...a He valve? 

The effect it had could have related to repeatedly pressurizing the fuel
systems--it seems to be conventional wisdom at this point that there is now a
leak in the 400N propellant in the engine--or *possibly* been related to voltage
spikes that operating the valve might have induced on the power buses. I wasn't
clear from reading the code as to how fast the valve was being cycled. But the
two loops built into MANY_ARMS seemed to be set up to run as fast as they could;
in a threaded interpreter that can be pretty darned fast...and the only thing
that seemed to be a delay was WAIT10, executed once on the way into and again on
the way out of the word. Not inside the loops.

I just have this mental image of a solenoid-operated valve cranking away like a
doorbell buzzer. That's probably mistaken, I hope. 

 73 de Maggie K3XS 

-- 
-----/___.   _)   Margaret Stephanie Leber    / "The art of progress  /
----/(, /|  /| http://voicenet.com/~maggie   / consists of preserving/
---/   / | / |  _   _   _    `  _AOPA 925383/ order amid change and /
--/ ) /  |/  |_(_(_(_/_(_/__(__(/_  FN20hd / change amid order."   /
-/ (_/   '  K3XS  .-/ .-/    ARRL 39280   /___ --A.N.Whitehead ___/
/____ICQ 7161096_(_/_(_/__AMSAT 32844____/ <maggie@voicenet.com>
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