Satgen306  Satellite Hindsight No5   by GM4IHJ                  4 Feb 95
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The recent launch of a major TV sat, saw it producing quality downlink
multi channel TV just 3 weeks after its launch. RS 15 launched a few weeks
ago worked on its first orbit. Contrast this with several recent Amsats
which :- 
a. Required at least one year or more in space for setting to work before
   being operational
b. Or/and have since spent several more months non operational because of
   software problems or reloads.
If a satellite costs say 200k, and it is only useful for less than 75% of
its time in space , we waste one satellite in four.
Equally interesting is the rising cost of getting a ground station equiped
for satellite work.
RS15 which has just overflown this station with 23 users on it, costs at
most 1000 sterling for suitable new ground station equipment.
By contrast Oscar 16 ( 1 user part of the pass ) costs at least 2000
sterling by the time you add computer, antennas , controllers and modems
etc to suitable transmitter and receiver.
Still further up the scale Oscar 13 ( 5 recent users ) requires complex
antennas, antenna controllers and pre amps over and above the kit required
for Oscar 16 , putting its costs up to about 3000 sterling if you are to
get regular access.
So are we in danger of driving folks away from Amsat, because we use our
funds inefficiently and then surcharge the ordinary radio amateur several
thousand pounds , which they can only justify if they can then master the
technical problems of satellite operating.
It is clear that there is a great deal that will need to be done if we are
to change the above situation. But it is of course unfair to suggest that
Amsat is alone with these problems. One look at the costs and results of
this last decades Japanese direct broadcast TV sat history is very
illuminating. All told between 1984 and 1989 4 Yuri Direct broadcast to
home dish TV geosats were launched along with a High Definition TV system.
All 4 sats failed or were left behind technically. Initial failure of the
first 2 put the program in jeopardy and expected sales of high definition
TVs in Japan simply did not materialise. Meanwhile, massive improvement in
US and European Low Noise front ends (LNBs), meant that the 3 channel hi
powered Japanese satellites were overtaken by European sats with 16 or 24
channels and faultless performance on standard PAL TVs. All of which was
bad enough luck for the Yuri builders and supporters,but since then to
make matters worse, Dutch/British digital TV has now demonstrated its
potential to provide an up to 10 times or more increase in useful channels
for the same bandwidth and/or a much better form of high definition TV.
Space here does not permit a detailed review of some of the other
instances of how to burn million dollar bills ( French TDF, British BSB
Squarial are typical examples). So perhaps Amsat has not done too badly
after all, although as IHJ school reports used to say " could do better ".
73 de John GM4IHJ @ GB7SAN