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Re: so35



On Mon, 5 Jul 1999, Bruce Paige soap-boxed:

> first is the over use of power ....  then  n4zq and myself dropped down
> to 5 watts and we sounded just as good.

Agreed!
Having completed a weeks worth of HT testing via MIR using rubber ducks
and being 100% successful, and having done the link budget, there is
absolutely no need for any power over 5 watts on ANY OF THE BIRDS except
AO-10.  The problem is congeston.  So people add power to 50 watts
to override the QRM and then add a 160 watt linear and an OSCAR array
to make sure they can step on all the 50 watt stations too.

This is not good operating practice.

In my opinion, the uplink budget should be calculated for all birds and
published.  All stations must be encouraged to use only that power
(ERP) for routine operations.  This assures two things:

1) A level playing field
2) less QRM as we get more and more sats in orbit using shared freqs
3) Allows URGENT, or EMERGECNY use by 50 watt stations if needed.

Unlike terrestrial comms, if 5 watts will do it, then 5 watts will do it
always.  Unfortunately, many of our spacecraft are not attitude
controlled, so there is variance in the path, but we should just let
that be a way of allowing SOMEONE else in who is in the peak, and we
wait our turn until the peak comes back to our area...  We should not just
RAISE power.

As we go to more and more mobile and portable operation thorugh more and
more satellites, we must allow for the distinction between routine (fun)
operations, and urgent-critical-important communications.  With FM, that
distinction can easily be made with power.  5 Watts for everyone for
routine. Whatever it takes for emergenceies...

AMSAT worldwide must take the lead in setting uplink ERP standards for all
of its birds and publishing them in all listings as a matter of routine.
The AO-10 OSCAR arrays are needed for the NON LEO birds, but they are
great overkill on all the LEO's.

Not only that, but it feeds the mentality that you have to have a BIG
OSCAR station to work the satellites and it keeps many newbee's from
joining us, when in fact, the OSCAR array is of diminising value on any
satellite other than AO-10.

Take the PACSATS for example.  ALl you need are 4 elements on UHF for the
downlink and 5 watts to an omni antenna on the uplink.  But everyone runs
50 watts and an OSCAR array to make sure..  THats about 1000 watts ERP
compared to the needed 5W.  But since that is what everyone else runs,
you need to do it just to hang in there.

The QRM would be THE SAME and the success for all stations would be the
same if they ALL dropped to 5 watts too.  Of course if there is other man
made interference such as Taxi's in Central AMerica or Pizza deliveries in
Timbuktoo, then more power by everyone is needed...  oops... I ramble...

de WB4APR




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