Gerald, Scott,
The satellite is the moon of course. With current and free WSJT
software there is no need for the gigantic antennas that have been
used in the past.
I have used WSJT, and at first it was quite impressive to see how it can
dig information out of signals buried deep in the noise. But my interest
quickly faded, for the same reason that I don't do DX in the usual way,
nor take part in contests: I'm looking for meaningful communication! And
that's not possible in WSJT. It just provides the minimal interchange
required to have a "legally valid QSO". I'm not trying to fill my
logbook with thousands of "contacts", nor to fill my walls with dozens
of (purchased!) awards for having contacted so-and-so many stations from
these-and-those places. What I'm looking for in ham radio is technically
interesting things, and real communication. WSJT provides the former,
but wears off quickly, and it definitely doesn't provide the latter.
Seems a bit wasteful of time and expense to implement any man made
satellite for amateur radio purposes considering the capability
already in place.
It's a totally different thing. The best ham satellites, for me, were
the store-and-forward pacsats. There was a numerous worldwide community
of hams posting meaningful messages, stories, photos, software, etc, on
those sats. The moon definitely doesn't replace that! Nor does HF. And I
regret to say, but have to, that what does replace it best is the
internet, rather than any ham-owned, ham-developed or ham-operated system.
And for meaningful DX QSOs, those in which something could be discussed
for some time, there is still no replacement for Phase 3 VHF/UHF
satellites. On AO-13 I could talk for an hour or two to someone far
away, about interesting technical matters, since all people operating on
the sats had at least some technical knowledge. If I try that nowadays
on 20 meters, firstly its hard to find any ham interested in a technical
conversation, and secondly it doesn't take even two minutes before
somebody "spots" me on a DX cluster, and the next moment there is a
pile-up of deaf prefix hunters calling me without even hearing me,
disrupting my ongoing QSO.
As you can see, I miss the good old times of good old ham sats!
But where does the notion of no useable satellites come from?
In part it comes from location, and for two reasons: One is that there
are no high orbit sats now, and that low orbit sats have a coverage
circle of about 2000km radius at most, and that there are very few
sat-equipped ham stations within that circle from my location. Instead
over North America or Europe there are hundreds, if not thousands, of
ham sat stations within that circle. And transponder/repeater sats are
usable only if there is someone to talk to, within the coverage! And the
other reason is that the owners of several sats, starting in the late
'90s, have opted for switching the sats on only over densely
ham-populated areas. Those sats will be on, and transmitting on high
power, often at a negative power budget (consuming battery charge), over
North America and Europe, and will be silent, recharging their
batteries, everywhere else. Some have been programmed to switch on when
over the northern hemisphere, and off when over the southern. So I never
get a chance to even detect those sats, except when their clocks shift,
they come on a bit early, and I just hear them for a few seconds at the
end of a north-going pass!
Instead the phase 3 sats could be accessed equally well from the
northern and southern hemispheres, so the field was even. This was not
always planned - there were sats that were intended to have Molniya
orbits favoring the northern hemisphere, but which failed and ended up
in orbits giving about equal chances to all!
And the Pacsats of the first generation, both the Microsats and the
UoSats, were always on except during power shortages, and had orbits
that offered the exact same access in the northern and southern
hemispheres. That, combined with the fact that one didn't need another
ham within the sat's footprint, led to a boom in satellite operation
among hams in the southern hemisphere.
> There
are at least 5 (+) reliable LEO linear transponder satellites, and
I've yet to listen to an orbit where there isn't activity.
Could you list them? I would like to specifically search for them, and
see which ones are actually operating when over my area. The last time
when I spent several days collecting information from the web, then
searching for sats on UHF, VHF and 10 meters, was almost exactly one
year ago. At that time I heard Tigrisat (useless for hams), Bugsat-1
(also useless for hams), FO-29 (VHF/UHF linear transponder, operating,
but with no users), Itupsat-1 (useless for hams), another Cubesat on
437485 from which I captured just a single packet (CQ>KD8SPS), and some
very weak signals on 437420 or 437415, which I didn't manage to decode.
All the other sats which according to various web sites are supposed to
be active, could not be heard here.
This is with the same antenna, preamplifier and radio that I used in the
90's to work many sats, with signals up to S9+20. So I don't think my
station is deaf.
I also made such surveys in previous years. The longer back we go in
time, the more active ham sats there were, coming to a peak in the
1990's. I remember a time with 7 fully active pacsats, 2 poradically
active ones, 2 high orbit sats, 2 low orbit analog transponder sats, two
or three FM repeater sats, plus a digitalker and several telemetry-only
ones. That's just counting VHF and UHF! There were additional signals on
10m, and a few sats had some downlink in the 23cm band too.
Five reliable sats with transponders, that would be great... Specially
if there actually was activity on them! If that turns out true, I would
return to some sat activity!
And the
old Yaesus have been fine for accessing them with half way decent
antennas, without preamps.
On VHF a preamp really isn't very useful, indeed. But on UHF it helps a
lot. I have preamps on both bands, and when I use the 2m preamp I have
to put an attenuator at the radio's input, or it will overload on strong
repeater signals within the band. The minimum discernible signal with
that preamp and attenuator combination is just about 1dB better than
without. Band noise is the limiting factor. But on UHF the band noise is
way below the cable+receiver's noise, so a good preamp at the antenna
feedpoint helps by several dB, and that's noticeable.
Granted it's not AO-13, but plenty of fun to be had - we had more
interest from younger, newer hams in our Field Day satellite station
than just about any other thing.
I can imagine. The problem is likely that somebody who has operated a
lot on the phase 3 sats and the pacsats in the heydays of the 1990's,
running a satnode and a satgate, isn't too interested nowadays in making
a few occasional 2-minute SSB contacts with a very few relatively local
hams on an analog transponder... Specially not when the other station
lacks proper TX and RX Doppler compensation, and has to be chased across
the transponder!
And of course there still is a lot of ISS activity with schools etc,
Again, location! Almost all that activity takes places over North
America, and some over a few other select places of the world, but
hardly here in my area. And the ISS is in a very low orbit, so its
coverage is even smaller than that of a typical low orbit sat. When the
ISS ran some permanently active ham system, such as a packet mailbox, I
could use it, but the occasional activity with schools happens far
beyond my radio horizon.
OK, satellite cheerleading over.
Really we are getting "a little bit" off-topic... Sorry, folks! I will
try to behave! ;-)
Manfred "past times were always better"
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Visit my hobby homepage!
http://ludens.cl
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