[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: AO-7 10m bcn, switch-on delay

 "Jay, kf6rmg" writes:

>    One thing I found interesting about this pass: AO-7 was supposed to exit 
> eclipse around 0319 UTC and AOS was supposed to be at 0323, but I didn't 
> hear the beacon until about 0334.
>    1. Is this delay of approximately 15 minutes between the satellite 
> entering sunlight and sitching-on occuring during every orbit?
>    2. Is the delay always the same duration?
>    3. Is the delay only occuring when the satellite resets in a certain mode 
> or modes?
>    4. Could the delay be the time it takes for the satellite's systems to 
> reset, ot should it be reseting instantly as it hits sunlight?
>    5. Could the delay be why some are reporting passes as being "dead"?

Thats what I've been trying to find out. Of course it should turn on and off
at just about the same time as it hits light/dark. The feeling I have so far
is that there's a twilight period when the sun's low on AO-7's horizon. At
these times, voltage production is less than nominal and that could affect
the reset electronics. Seems to fm around these twilight periods and get much
better after a while. Maybe some temperature factors as well but I'm less
certain about this.

Of course, there's also the sun angle on the solar panels as well just to
complicate matters even more. I just spent some time with a world globe and
a satellite model. The polar flipover, for want of a better term, could cause
very poor sun angles at the medium latitudes, so people closer to the equator
should see less of this problem. Do they ?

Hey, we're all learning some fascinating stuff from this experience.

Richard W L Limebear G3RWL
FOC # 1188

          So many beautiful girls ..... (sob) so little time
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org