[amsat-bb] Eagle costs

["Robert McGwier" <rwmcgwier@xxxxxxxxxxx>]

Most of these arguments are moot. The transponder packages are
almost in the noise compared to all of the other costs.  If we
flew ONE transponder, it might cut down the costs by a few % given
that we get a ride (including the new DoD based rides mentioned
here that we are INDEED exploring).  The design goal is all transponder
to be on that can be on all the time.  You should hear the very good
discussions when someone says I don't want to or I think I can't.
We have universally wanted to stay away from "experimental Wednesdays"
or K band day per month.  This prevents "market penetration".

That means a very good analog transponder and a very good digital
transponder to be run simultaneously.  We probably could not put
more power out on EITHER of them if we wanted to because we
cannot conduct the heat away without adding an extremely massive
and very costly heat pipe system.  Right now, we have the
design goal before us of 7/24/365.25 operations.  Dick Jansson has
been positively BRILLIANT (hear my talk at the annual meeting where
I will present his results) and given us 100w and up to 150-ish watts,
but 100w minimum.   The digital package design can give up
elements on transmit to reduce power load and require larger
ground station antennas or lower data rates when we have to reduce
the power.  Given that you have a hard to find ride to highly
elliptical orbit,  it simply makes no sense to waste it on a cheapsat.
This would require you the user to have an EME station to talk to it.
I don't believe you are engaging your neural parallel processors and
figuring out the link budgets.  GO BACK and read the history of
Oscar IV to see what happens when you put a dumbsat out at HEO.

1) Given that we do not wish to limit our user base to wealthy hams
who can afford to put up large EME arrays,  we must point the
satellite with gain antennas at the earth and keep them pointed
at the earth.

2) Given that we almost surely will not get a ride all the way to HEO,
we will need a rocket motor.


Paragraph 1 and paragraph 2 account for 90% of the costs. Design,
travel, parts, reviews, testing, etc.


As Mike says "A closed mouth gathers no feet".

Bob
N4HY
----
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org