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Re: amsat-dl statement


Thank you very much for this update!

Your comments have greatly restored my hope that AO-40 will be back on
the air. I was beginning to fear the worst.

Thank you also for all of your time and hard work on this fantastic

If you have time, I'm sure everyone at the AMSAT-BB would love to hear
some of the details of the preliminary testing done since AO-40 achieved

Thanks and 73's,

Darrell Bellerive

Peter Guelzow wrote:
> Jon Ogden wrote:
> > If the computer has completely crashed, there is no
> > battery regulation or charging control, etc.
> The BCR does not need the IHU to regulate or control charging. The
> IHU is only used for optimizing the battery set-point and solar array
> offset voltage to get *maximum* efficiency..
> > Again, flame me if you want, but it's a little difficult to hear the
> > designers of the craft telling us that it will reset itself but that they
> > just don't know when.  Huh?  They designed the circuits with certain
> > parameters.  I don't know, I am just bummed and depressed.
> >
> This is also not correct and there might be a misunderstanding.
> A timeout was expected on Saturday. There were no observations and
> command stations tried to re-establish communication by sending
> blind commands.
> Assuming that no commands have been accepted by the IHU-1 since contact
> was lost on Wednesday, a COMMAND-ASSIST watchdog will be invoked
> at orbit=65, MA=0 which is 2000 Dec 21 [Thu] 23:55 utc.
> The COMMAND-ASSIST routine will cycle through various RX, TX, Hi-gain
> and Low-Gain antennas..
> If commands were received by the spacecraft (although we have not
> seen any successful commands so far), than the COMMAND-ASSIST watchdog
> will be reset for another 10 orbits. In this case we may see this function
> happen not before Dec 25.
> Please note that this is a *software* watchdog. There is no hardware
> watchdog. If the IHU has crashed, than a RESET command can be issued
> from ground. This would be the last resort. It is a very fail-safe
> system, which has been used before on AO-10 and AO-13.
> However, it was decided to check and analyze all other possibilities
> before issuing such a drastic command. There is no need to hurry and
> we don't want to miss any option...
> > >There are various serious reports about very weak PSK signals which
> > > seem to be coming from AO-40. The commandteam is verifiing these reports..
> We also got reports that these signals might be "fake" PSK signals sent
> by someone through AO-10, which was visible at the same time.
> The command team is still very interested in any signal report, but please
> make sure that these signals come from the right direction, etc..
> 73s Peter DB2OS
> ----
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