On Thu, 9 Dec 2010, Peter Laws wrote:
I've had my coffee (decaf, granted), but I'm still confused.
G-5, the rogue satellite (NOAA product generator, note spelling :-), has it's
transponders on and is transmitting.
It's G-15, and the NOAA product generator is SES-1. I'm horribly confoozed
as to what you are saying here.
Hauppauge (where the PC TV tuners are grown) is in the footprint of G-15, but
Hawai'i is not.
Correct. Maybe.
what I don't get is how the fact that NY is receiving G-15's signal affects
its ability to uplink to SES-1. And because HI is not receiving the rogue
signal how does that make uplinking different?
If G-15 was interfering with SES-1's ability to *hear* NY, that would be one
thing, but how would transmitting from HI make that better?
Here's how it works...
G-15 will pass close enough to the satellite that parts of the country
will get interference, while others will not...at least that is the hope
right now. Think of this as a longer version of a "sun outage" that we
get every spring. Looking up from Earth, you would see G-15 passing in
front of SES-1.
But that's in New York or the east coast. So that blocks both uplink and
downlink. If you have the uplink in Hawaii, then some of the country is
unaffected. Then, at some point, switch back to NY/WV/VA or whatever one
you desire, as the bird moves away, and we're golden. But wait...
The huge unknown is how wide that interference area will be. With sun
outages, it's predictable, because you know the exact location of
everything. With the satellite, you have an idea, but...and here's the
key...you also have 40 watts of signal across numerous transponders
blasting away signal at Earth. So you also have that LARGE footprint of
potential unwanted severe interference, and that footprint is going to be
much, much wider than the bird itself interfering with it.
So inevitably, my hunch is that if you have a full-power signal on Galaxy
15 on the same signal as NOAAport, we could be hosed no matter what; it's
just that the outage time will be less if it's sent from Hawaii to start.
Intelsat says that the fly-by will be on December 15th; and the predicted
outage time is 2-8 hours. But the transponders could start interfering
days before it even reaches that point. The other broadcasters were
successfully not interfered with on other satellites because they got
transponders on other birds until G-15 moved past their home base. But
the NWS doesn't have a backup bird to go to...and that's way so not cool.
Folks, make sure your EMWIN and backup feeds are ready. UNIDATA, is there
ANY way we can get an Internet/Internet2 NOAAport feed for 5 days to be
turned on manually until this event is over with? Can we beg, grovel, take
someone out to dinner or far better, give them a UNIDATA T-shirt to have
a backup NOAAport feed through this mess?
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Gilbert Sebenste ********
(My opinions only!) ******
Staff Meteorologist, Northern Illinois University ****
E-mail: sebenste@xxxxxxxxxxxxxxxxxxxxx ***
web: http://weather.admin.niu.edu **
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