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Re: Re: Thoughts on future "FM birds"



At 05:33 PM 8/17/2000 -0400, you wrote:


>>Laura, as I see it the fundamental point is to sell lots of 2m FM radios, 
>>not to enable communications, or further satellite development.  The same 
>>stupid thing is being done on ISS, and I for one, think that is a bad 
>>idea.  SSB all the way!

Does that mean no more 9k6 digital birds?

Are you willing to help finance a LEO SSB transponder right now?

>>            73, Dave wb6llo@amsat.org
>
>  Instead, I think it is a misguided attempt to convince people that 
> satellite operation is not inherently difficult or challenging.

The satellite builders are not writing the articles for CQ, QST etc on how
easy it is to use a FM bird.  Once again the builders primary use is for a 9k6
digital to link to the satellite. It just happens if they put it into 
analog a lot of
people try to use it.  Every time one of these article are published the 
satellites
become a MESS!

>   I think that this is a mistake.  Frankly, if satellite operation didn't 
> involve learning a lot of new things, I for one (and I suspect you too) 
> would never have become interested in it.

We are learning how to build satellites not SSB transponders.  If you can
build a transponder that includes a digital channel I am sure some of us will
fly them instead of paying $10 thousand or more for what we are flying now.
Maybe I am wrong and many of you are helping out the students building
satellites in the Universities near you.

>Laura's right, and its about time someone said so.  It does seem a bit odd 
>that people select a technology that is wholly inappropriate to satellite 
>communication and then appear surprised to find that it doesn't work well.

At least they get used all the time.  If they were activated on random passes
then they would not be as crowded. FSK FM links work just fine for command
and control.  On our next satellite we can turn on packet digipeating.   If the
same numbers try that as are trying UO-14 now it will also become a mess!

>But there may be some method in this madness.  I think the basic theory 
>behind FM satellites is: 1. It costs a lot of money to launch a 
>satellite.  2. If you can convince people that handheld to handheld 
>satellite communication over hundreds of miles is possible (maybe easy) 
>via these satellites, lots of new people will join AMSAT and help finance 
>them, and 3. After a few weeks (months)  they'll get tired of this and 
>graduate to satellites that work better.

So AMSAT-NA is taking advantage of us satellite builders. Maybe we
should get a kick back (Hi Hi).  When has AMSAT-NA put up a FM bent pipe
only bird.  Maybe they did help out on AO-27. I do not know.

Can P3D support all the ARRL members who help contribute to the satellite
if they all try to get on?

>You can pick apart the logical flaws in the above as easily as I can, but 
>I don't know that this theory has been proven incorrect.  However, even it 
>it works, there does seem to be something sort of sneaky and misleading 
>about it.

I agree,  I would not give a demo using UO-14 if it was in view of the east
coast. If I used the far west coast pass it would be very misleading.


>As for ISS, I found reading the book Dragonfly to be quite an eye opener.

One thing that the UO-14 FM bent pipe is doing on the central USA Saturday
morning pass is letting you hear what the astronaut hams heard on the
shuttle when operating SAREX.

Randy N7SFI

I do not see a satellite for the masses.  Maybe more effort should be to link
local repeater via amateur satellites.  Isolate them from using the satellite
directly so they will not be able to overload the SSB transponder by running
to much power. Use wideband digital voice  on a microwave transponder for the
links. But who would pay for this if it can be done cheaper by using the
Internet now.

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