its rocket engines. when launched they don’t use on board fuel to launch them - they often have boosters attached that can be remotely controlled to burn up in the atmosphere.
they want to keep as much fuel on board to allow for maneuvering in orbit
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Wouldn’t they need power to move constantly so it stays at say 152 or 160 E as the Earth spins and rotates around the sun? Or does gravity achieve this?
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gravity, they’re in geostationary orbit
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gravity, but they do need occasional lifts to stay at 36,000 km (which means there orbit time around the earth is the same as the earth, meaning they appear to be in the same place from the ground), as opposed to the international space station which has an orbit of about 420km and has a 90 min orbit time
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For a geostationary satellite it has to stay on station in a box about 20Km square in order that it is in the middle of where all the fixed antennas on the ground can see it. If it moves off station initially the higher gain antennas will lose it then eventually all the lower gain antennas will lose it as well(their beam width is wider). The satellites have usually a small reservoir of a monopropellant like hydrazine and a thruster to keep it on station. That fuel is what determines the life of the satellite. As it starts to move off station it appears to do a 24hr period figure of 8 from the ground. The further off station it gets the bigger the figure of 8. You can still use them for point to point traffic if your antenna has a tracking system installed.
Some also have a gyroscope wheel that keeps their solar panels pointed at the sun and their high gain antennas pointed at the ground.
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When a satellite is launched, the rocket only reaches a certain altitude. To get to it’s final orbit, about 36000 km up, the satellite needs to perform an apogee burn. This should only use half of its onboard fuel. The rest is used over the life of the satellite to keep it on station, and later move it to graveyard.
D2 is needing to move to 160 because D1 doesn’t have much fuel left and its replacement, as noted earlier in this thread by someone else, won’t be ready for quite some time. I believe D1 will be moved to 152, provided it has enough fuel and be inactive. This is to hold the slot vacated by D2.
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Intelsat19 C Band
3954H sr7000
1080i H.264/ 8x MPEG 2 Audio
“EDM NY: ENC 432”
WSL Surfing from Sydney
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Don’t know if this is the right spot but some satellite license checking numbers chucked up in India:
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What sat was this on
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No clue, taken from a highlights video.
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Ahhh ok no dramas, looks like Asia Sat 105E
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Hi, Anyone have any tips for receiving Intelsat 19? I can get Optus D3/C1 very strong however am having trouble finding Intelsat 19. Only other signal I can lock on to is weak and has a few unnamed feeds. Would anybody know what this satellite is? Thanks.
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Make sure you have the skew on your LNB correct as it is different to the other sats around the 150s region… I have also found if you don’t get it quite right you end up with not only weak signal but picking stuff up on both H and V at the same time eg. as per in the case of the TP below you will get TP 12686 on both V and H, when you should only get it on H
I have found the easiest TP to align to is 12686H
https://www.lyngsat.com/muxes/Intelsat-19_Australia-and-New-Zealand_12686-H.html
Hope this helps
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Thanks for the tips! Its been a while and I’ve finally found it. I can only receive one transponder though which is 1264.000 V and it has a lot of Middle Eastern/African content on it, Kuwait TV, TV Charity, Sudan TV and Al Jazeera seem to be the only non encrypted channels to watch on it other than some audio ones. I’ll try and reposition the dish a bit and see if I can access some other transponders.
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Changes to ABC/SBS Self Help Services
https://www.myvast.com.au/vast?id=self_help
The distribution of ABC & SBS Digital TV services currently carried on Optus D2 satellite at 160°E will start transitioning to alternate satellites starting 30 January 2024.
This satellite service bulletin is provided to self-help retransmitters who use the ABC & SBS Digital Television Service Distribution (DTDS) feeds as input feeds to self managed transmitters, to inform them of the changes to the delivery of these feeds and the actions they need to undertake to keep receiving these feeds.
It is critical, that self-help retransmission providers follow the instructions in this bulletin within the timeframes described in this document if they want to ensure continuity of ABC & SBS digital TV services. Alternatively, self-help communities can transition to using VAST services to continue receiving ABC & SBS services.
Western Australia, Northern Territory, Queensland (ABC & SBS)
Alternate to Eutelsat 172B (at 172 East) - 11043.75 Mhz Vertical
All States (ABC Only)
Changes frequencies on Optus D2 (1st April 2024) - 12657.5 Mhz Horizontal
WA/NT/Qld don’t need to change if shifting to Eutelsat 172B
NSW, Victoria, South Australia (ABC & SBS)
Alternate to Measat 3a (at 160 East) from 15th July 2024 - 12356.5 Mhz Horizontal
(Optus D2 currently occupies 160 East (and its replacement isn’t due until late 2025), So is Optus relinquishing the slot or is Measat sharing it? Also, 3a is already deployed, so is it moving or is it a misprint?)
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Something isn’t right about that. Measat 3a is supposed to be at 91.5°E.
But what I don’t understand is, why WA needs to point at a satellite so far away? The elevation will be pretty low.
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Seems to suggest that whatever ends up at 160 is going to have limited coverage in those markets.
If it does transpire that Measat 3a is moving to 160, it only has 2 small Ku beams for Malaysia/Singapore/Indonesia that would only cover the southeastern part of the country.
http://www.measat.com/wp-content/uploads/2018/07/M3a_temp.pdf
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Pointing to 178°E will end up with an elevation of just 20° in Perth (though it probably won’t be pointed to from there). I know people who are already complaining about Intelsat 19 at 166°E.
It’s highly unlikely that they’ll move Measat 3a. Going from 97 to 160 is a big move and will use up quite a lot of the fuel, decreasing its useable life. When D1 moved from 160 to 152, they had to do it very slowly because of the lack of fuel it has.
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The TBS transponder on IS-19 (12606H) was shut down this morning at 3am AEDT due to a power anomaly on the solar array and will not be restored. As far as I’ve heard, broadcasters did not find out until after it happened (edit: they were only given a few hours’ notice).
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not good when the satellite already had power issues at launch