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Re: AMSAT has a SECRET!




> ......AO-40 is a HUGE success........

Ditto ! The amazing amount of planning and engineering that went into AO-40
is what turned a "catstrophic event" into mission compromise. We still have
a very capable satellite up their with alot of capability we haven't seen
yet.

Encouraging the migration to mode U/S and L/S will do more for promoting
satellite operation than perpetuating the need for large V/U antennas. No
one can say that S band downconverters are hard to find or expensive. I
spent more money to fill up my Honda this morning than I did for my
Transystems downconverter !

Bent pipe transponders are useful, but you can't ignore the tremendous
advantage of having on-board signal processing on the satellite. With a bent
pipe transponder the link budget requires the uplink signal received by the
satellite to be higher than the combined effects of both the uplink AND
downlink additive noise. With on-board regeneration, the uplink signal only
needs to be above the uplink additive noise. This allows lower EIRP at the
uplink station (read smaller antenna, less expensive transmitter) and lower
power on the satellite (read smaller batteries, better power budget). The
"cost" of this is some computer power on the satellite. I think this will
become more apparent when RUDAK is activated.

I always thought part of our charter was to push the envelope a little and
see how much we could accomplish by substituting ingenuity for money.
Certainly, the FCC thinks we should be doing this, otherwise they wouldn't
continue to let us use billions of dollars worth of radio spectrum for free
!!

Sorry for the long post... I fully support the new initiative by the AMSAT
BOD and again thank the entire AO-40 team.

Howie
AB2S

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