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Re: New satellites for beginners / new members????



On Thursday 24 July 2003 17:08, Dave Guimont wrote:
> > I knew it would be an exercise in time wasting to explain to him the many,
> many, wall to wall
> contacts hundreds of us made on O7, O8, FO12, and on and on with
> "transponder" birds...And many of them at the same time, with simultaneous
> wham, bam, thank-you-maam contacts for those that chose to make them...

So what happened? Did the phase 3 satellites spoil them.  I have never head
"wall to wall" contacts  on FO-20 or FO-29 and I hear when AO-21 was in a
transponder mode it was mostly empty.

Since local noise blocks most of the mode A downlink on ten meters at my QTH
I do not know if RS-12 ever had wall to wall contacts on it other than the 
"wall to wall" dits on field day.  I guess if IPL happens a lot more of you
will have the chance to have S-9 noise on 10 meters.

As I see it we can stop arguing and except the following:

Orbit         Band        Modulation.
-------------------------------------------------------
LEO           A/K              SSB transponder
LEO           B/J               FM  Voice and/or Digital
HEO           B/J/S-band   SSB transponder.

So the real argument is if we want to put up several LEO's, (one of each type) 
since they will be cheaper than one HEO which will require on board 
propulsion and active atitude control to point the high gain antennas
back at earth.

For the paper chasers do we put up a satellite for WAS/counties/grids or one 
for countries/grids.  It looks like DXCC is twice as popular as VUCC but I
bet a lot of hams with DXCC also have VUCC.

Maybe, as was done in the past, let HEO's be international activities
so you can spread the launch costs around the world ham populations.
Let the LEO's be done by AMSAT working with universities who have
the launches.  When I was working on JAWSAT I would have loved 
to have flown a PSK telem downlink/SSB transponder package from
AMSAT.  Right now it is easier for a student payload to use FM for their
control and telemetry. Once they have done that it is easy to add a FM bent
pipe so they are more than a bleep/bleep box.

FM can work on a LEO. Look at SO-50. If it is a little harder and not on every
pass you cut the traffic way down.  I would have thought after all the times
it is been mention on the net that the number of hams using it would increase.
I am not seeing that happening.

Why couldn't new LEOS have both  HF transponders and UHF/VHF FM and
alternate them if the power budget can not hander both on at the same time.

73,

Randy N7SFI


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