[amsat-bb] Re: ARISSat-1 voice telemetry 00:27z 8/21/11

[Greg D.]

Ah, interesting.  So, values around +/- 0 mean that the battery is (or thinks it is) fully charged, and the satellite is running on just the solar panels.  Since that happens pretty quickly after start-up (low MET values), that certainly supports the conclusion that the battery has nearly zero capacity left in it.

But if it's "fully charged", there must be something else going on, because I've heard passes where the satellite appears to be in "high power" mode - several voice, SSTV, and telemetry segments back-to-back - then suddenly turns off after one of the segments.  This is where the reported battery voltage has remained in the mid- to high-35 volts range, consistent with high power operation.  Did the satellite happen to spin to a less favorable angle for a moment between telemetry readings, causing the low power mode threshold to trip?

Playing Armchair Sherlock,

Greg  KO6TH


> Date: Mon, 22 Aug 2011 17:41:29 -0400
> From: aa2tx at comcast.net
> To: ko6th_greg at hotmail.com
> CC: amsat-bb at amsat.org
> Subject: Re: [amsat-bb] ARISSat-1 voice telemetry 00:27z 8/21/11
> 
> Hi Greg,
> 
> The battery current is not really negative
> under these conditions. This is just a small
> drift in the zero point of the measurement.
> 
> 73,
> Tony AA2TX
> ---