[amsat-bb] Re: Arissat-1 Voice telemetry analysis from G0SFJ

[Greg D.]

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: andythomasmail at yahoo.co.uk
> To: amsat-bb at amsat.org
> 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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