[Ground-station] Rent-a-GEO transponder prices.

[Wally Ritchie]

As Phil Karn has pointed out, these satellites have uplinks that operate in
the frequencies allocated for earth to space fixed commercial activities.
They must be licensed, one way or another, to operate in those services.
The spacing between satellites is very close. Every satellite sees every
signal pointed its way from an area as large as 1/3 of the globe. Different
polarizations, overlapping bands and sophisticated scrambling codes are all
used in attempts to keep interference under control. Because a single bad
operator can render an entire transponder useless, transmissions must be
carefully controlled. Uplinking to these satellites is NOT a ham-like
activity. Unlike the 6-Meter TV RFI problems in an adjacent apartment
buildings (a common occurance in the 60's), just imagine a single ham
bringing down a few million subscribers of Direct TV.

QO-100 is viable because the uplinks are in s-band allocations for amateur
radio satellite service earth to space uplinks. The manufacturer (MECO) of
QO-100 made modifications to meet specifications engineered by AMSAT-DL.
These specifically enabled the operation of two spare transponders with an
S-Band uplink and X-Band downlinks. This was technically feasible for MECO
without great difficulties only because the S-Band uplinks were close to
existing S-Band control channels and the X-Band Downlink was adjacent to
the existing downlinks. As often happens such technical feasibility was
shall we say enhanced by political considerations.  It is hoped that a
similar approach might be used in some future North American Satellites.
But I wouldn't hold my breath on this.

The advantages of a digital repeater over analog transponders is so great
that this path is the more likely path to service over North America. Of
course, if Es-hailsat enters the North American market, a future Es-hail -
X is not out the question.

As pointed out before, the use of a commercial space segment is not
something to consider for general amateur use. It is simply one alternative
for engineering tests of  future repeater downlinks. All amateurs (and
non-amateurs as well) would be able to receive such downlinks from the
commercial satellite. This could permit early testing of the downlink under
real-world conditions. Such tests will no doubt be done from the QO-100
wideband repeater as well. But hams residing in North America will not not
be involved.

We have lot's of spectrum for this application. That is not the problem.
Holding on to what we have is the motivation for many of us. If don't get
in operation soon, we risk loosing what we already have.

Wally
WU1Y





On Sat, Aug 24, 2019 at 6:27 PM KC9SGV via Ground-Station
<ground-station at lists.openresearch.institute> wrote:

> Interesting read on the evolution of rent-a-GEO transponder prices.
> We really need spectrum for legacy ham modes on a narrowband section of
> the rented transponder ala QO-100.
> This will equate to more customers paying the rent.
> Only 300 KHz is needed to emulate the 40 M ham band, which could be
> widened later.
>
> http://www.satsig.net/ivsatcos.htm
>
> Bernard,
> KC9SGV
>
> Sent from my iPad
>
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