W2 down ??

Let's hope Eutelsat don't employ someone like Red Dwarf's "Lister": Playing Pool with Asteroids could develop into something really nasty.
 
Analoguesat said:
Eutelsat have sent out an email saying W2 has depointed
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Although I've been on this forum for over a year I've never come across this term before. To put it bluntly, what is "depointed"?
 
For some reason a satellite can lose its Earth lock. In this case the craft automatically tries to put itself into a safe mode - normally so aligned that the solar sails are illuminated to keep the onboard batteries charged. Assuming the bird hasnt suffered catastrophic onboard electronics failure, its still operational, but as the transmission antennas arent pointing anywhere near where they should be all downlinks are lost. (Of course as the uplink dishes are also all awry theres nothing to come out of them anyway!)

The controllers are still in contact with the satelite so once they discover what went wrong they can start to realign the bird back into its correct orientations.

A depoint can also occur if a satellite is hit by space junk and starts tumbling.
 
Satellites have an IRES, an Infrared Earth Sensor, which senses the Earth horizons and then controls the spacecraft axes to keep it pointing at the Earth. Of course the strongest source of infrared is the Sun, so the spacecraft can occasionally get caught out and end up pointing at the Sun. This is particularly serious during the equinoxes when the Sun, Earth and spacecraft are aligned, and if it happens during the spacrafts 'evening', it would fall into the Earths shadow and the spacecraft could go into a tumble. The only way of rescuing it then would be to transmit a strong signal at it (usually at S-Band) and get it in a stable motion.

One of my mates works at a satellite uplink station, so I'll listen out for any good gossip about W2.
 
Im starting to think Eutel had an inkling the old girl was on the verge of failure - Sesat 1 has been whizzing round tha arc for the last couple of weeks ex 36E, and if the latest reports are correct W2M has been booted round from 3E as well.
 
12600V and 12633V are on, but signal is low but can watch RTK-SAT.

and 12656V.


Also 11061H,11471V,11513V,12648V OK.
 
qutoed by Analoguesat:
Sesat 1 has been whizzing round tha arc for the last couple of weeks ex 36E, and if the latest reports are correct W2M has been booted round from 3E as well.
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I reckon you might be right Analoguesat. I've inserted the latest Ephemeris from Celestrak (dated 27th for W2M and 28th for Sesat) into STK, and it shows them both around that location. Thats if the ephemeris is reliable.
 

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Well W2M and Sesat have reached according to _http://www.n2yo.com/?s=33460
 
Should start to get interesting once Sesat 1 and W2M fire up :)
 
Yep, W2M is definatley on station. This mornings Ephemeris from Space Track.org for Sesat puts it still 'passing by', so Eutelsat should do a burn to get it on station today.
 

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Both W2M and Sesat 1 are now reported to be on air at 16E. (Eutelsats latest press release)

All I can say is one of the birds isnt performing very well at all - many of the signals are MUCH weaker than before the failure. Als*t RTV has gone from one of the highest power signals to a horrible jittery mess on my 1m dish. :(
 
futumsch said:
Satellites have an IRES, an Infrared Earth Sensor, which senses the Earth horizons and then controls the spacecraft axes to keep it pointing at the Earth. Of course the strongest source of infrared is the Sun, so the spacecraft can occasionally get caught out and end up pointing at the Sun. .
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So..my somewhat poor attempt at a joke (post 12) ...was not so far from the truth afterall..
rgds 2 all
VS
 
Analoguesat said:
Both W2M and Sesat 1 are now reported to be on air at 16E. (Eutelsats latest press release)

All I can say is one of the birds isnt performing very well at all - many of the signals are MUCH weaker than before the failure. Als*t RTV has gone from one of the highest power signals to a horrible jittery mess on my 1m dish. :(
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Im getting level 88% and quality 52% with my channel master 1.2 iverto black ultra lnb and technomate 6800super+ Im not sure what the levels where before all this but no major problems here thankfully
 
Quite a few reports coming in across the forums of poor 16E signals from around the UK so its not just my set up here :D
 
part of transponders are with weak signal here, and movement of dish for 1-2 steps is critical
 
16e is more or less a no go for me at the moment. I can only see some of the ITV Partner channels, but they have a horribly high BER where as before they had none at all.

I cannot see any of the Digitalb, Pink or Tring channels and about 75% of the Total TV channels have gone also :(

Hope they sort this out soon as i watch a fair amount of stuff on this satellite O-no

Or should i say i used to :-lmao
 
Not too bad here, been able to watch some HD channels for free on 10976H DigitalB HD channels, now getting most transponders. A few on the weak side though.
 
Majority of programming now running.
 
Many signals now seem to have improved strengths so some tweaking must have occurred overnight
 
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