[amsat-bb] Longevity-sat proposal

[Cathryn Mataga <cathrynm@xxxxxxxxxxxxxxxx>]

Okay, I've been rethinking a little bit.  Got
some helpful advice. Here's another attempt.

1.  No batteries.   When it's dark, it goes off.
2.  No microprocessor -- all logic done with discrete parts.
3.  Orbit 10km high, roughly circular over the equator.
     (The idea here is to hopefully get an orbit where we could
     talk to the satellite using a dish and a linear actuator.)
     Would be a daytime satellite anyway.  Good
     for field day, things like this, I suppose.  Don't know how hard
     it is to get to this place.
4.  Satellite points toward earth using Gravity boom. Spin stabilized.
5.  Analog style circuits to insert a temperature and solar
     panel voltage as an analog signal back into the passband.
6.  2.4Ghz downlink.  Because we have all these people
     making an investment in AO40 equipment, and it'd be nice
     to leverage that.  Avoids the crowded 2m band.
7.  435Mhz uplink.  Here again roughly matching the most common
     AO40 uplink mode.
8.  High gain antennas pointed down toward earth.  Gain
     optimized to cover the planet from a circular orbit.
9.  Satellite uses some kind of analog circuit to maintain it's
      one bit state of being on and off.  I suggest maybe a capacitor.  We
     send a signal to charge the capacitor, and as long as that
     capacitor is charged, the transponder stays on.   We send an
     on signal now and then to turn the thing back on when it discharges.
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