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Re: An Open Letter To AMSAT




>It all depends on which command was the last one the satellite
>received .. there is a fixed timeout from the last command received,
>but which command that was is anyone's guess.  If the satellite
>receives any commands, that will reset the timer and delay the
>timeout that brings the satellite into command-assist mode, thus
>making it more difficult to reestablish telemetry and get a data dump
>that may have information on why the telemetry dropped out.
>
>As >


OK so riddle me this.  This doesnt exactly seem rocket science...

It strikes me as if we have a pretty simple solution set going on here.

1.  the satellite is recieving commands but not acting on them.  In theory 
it strikes me that the satellite would be getting commands that would try 
and make it "talk" to the ground so the guess would be that for a bit that 
they sent commands to the sat and then stopped because they decieded that 
the commands werent being recieved because apparantly none are being acted 
upon.

2.  So now that they have stopped sending commands they are trying to wait 
for this watchdog timer to reset.  When that will happen no one knows for 
sure because no one knows for sure the last command the thing heard.  Since 
they expected it Saturday that must mean that the window exist from whenever 
that backs up to to a last command heard right up until the time they 
stopped sending commands (and the time runs out).

3.  IF that doesnt do it then the ground stations could send this "master 
reset" command which in theory would crank it all up to start all over again 
with the possible "bad effects" that all are speculating on  (the mind 
starts to wonder how much worse they could be then not hearing from the sat 
for several days...).  For this to work (and I am speculating here although 
it could be cleared up pretty quick) this would require as a minimal thing 
that at least one command reciever be working and two the "master reset" 
circuitry be intact and three that their be something functional to reset.

So to summarize based just on what the folks have let us know it strikes me 
that 1) there is a window that closes at whatever time plus interval that 
the on board reset will fire then 2) there is a last ditch chance to send 
this master reset.  I would wonder what has to be working on the satellite 
for that to work...?

Whats wrong with the logic here?

Robert Oler WB5MZO
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