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Re: Oscar-Zero anyone?



THANKS FOR THE  RESPONSE.

I hope you all realise this was submitted a little bit in jest...and a
little bit "what if" someday way down the log page ;-)  my comments start
with **

>Erm, this has been done to death. :-)  
**Ah not in the few weeks I've been on the bb.  Of course there have been
other satellite suggestions that definitely have been thoroughly discussed!
 But, please, this was not offered as a serious topic...just a little
diversion for Christmas ;-)

>Firstly, the free space losses are sqr(400000/40000), or 100 (roughly, i.e.
>20dB.
**0oops:  did the miles vs km error.  Also, did anyone catch the perigee vs
apogee goof!  Maybe NASA will hire me back to help design Mars
missions...groan ;-)  {now where did I put that sliderule?}

>Secondly, due to libration of the moon, any fixed antenna pointing in our
>general direction needs to have a beamwidth of at least 10 degrees, which
>implies an antenna gain of not much more than many of the AO-40 antennas.
**That may be.  Ten degrees is ~20 dBi gain.  And I would think this would
suggest microwave freqs. so the ground station antenna gain is easier to
achieve.  In 20 years this may not be this hard.

>Tracking is the other option, which would lower the long term reliability of
>the system.
**Why tracking?  Other than libration, the moon rotates once/per orbit
around earth.  In other words, the same point on the lunar surface faces
earth throughout the lunar month.  {approximately}

Of course the ground stations will need to track...so what?  This isn't a
"everybody gets to do it with an HT" project.

>Thirdly, how is it going to be powered? (remember the 2 week lunar night -
>that's a lot of batteries and solar cells! :) ).
**Oh I figure we would just plug into Luna-Edison ;-)  Seriously-->Probably
not practical on a autonymous mission; only piggyback with some NASA
mission like a MoonBase. {which probably would have solar/nuclear isotopic
thermal-electric generation system}

>Then there's a host of other issues, such as thermal engineering (it gets
awful
>hot and cold on the Moon).
**Bury it!  {assumes a manned mission}{have shovel, will travel?}

>Would be rather expensive, to get it up there.
**Yep!  Morgage everything..its worth it ;-)

> EC> If it were part of a Moon Base, then maybe it would serve dual duty as
> EC> a morale booster like ARISS is for ISS.  Or rent out some telemetry
> EC> time for somebody's experiment.  We'd certainly would have no problem
> EC> with keps ;-)
>
>Well, if there was a manned moon base, it would become more practical, with a
>fixed power source and someone to aim very high gain antennas in the right
>direction, or watch over the computer tracking system and maintain the
rotators
>:).
>
>A manned moon base and possible ham station/transponder is a whole new ball
>game. :)

**OK, HOPE THIS WAS FUN...WE CAN DROP THIS ONE AND MOVE ON TO SERIOUS STUFF!
"now about that repeater on Mars..."

Cheers!
Ed

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