Hi Andy,
I asked a similar question about the battery current earlier, and the reply from the control team was that the battery is essentially not there - it's an open circuit - so there really isn't any current flowing at all. What we are hearing with the minus 8 ma current is really just a slightly offset "zero" reading. My digital volt meter does the same thing, giving a very slightly non-zero reading with the probes not connected to anything.
Greg KO6TH
Date: Wed, 21 Sep 2011 15:03:54 +0100 From: [email protected] To: [email protected] Subject: [amsat-bb] Arissat-1 Voice telemetry analysis from G0SFJ
I have submitted for a tlm certificate my analysis of the voice telemetry from Arissat-1 on certain orbits in September (when I was present, hi). The dates of the receptions in September are in the analysis spreadsheet.
The MET is decreasing, I think this is because the satellite comes out of eclipse and swithches on nearer the observation, as the orbit is precessing
I think the analysis shows that as the MET decreases, the IHU temperature decreases, and the battery current increases (this is a lesser negative number).
Put that another way, as the MET in sunlight increases, the IHU temperature increases and the circuit current decreases (greater negative number).
However I don't know why the circuit reports a negative current, or even if the voice tlm is accurate. I'd be grateful for any comments.
73 de Andy G0SFJ
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