Es'hail-2 on the move.

[G4EWJ]

The satellite is moving slowly east from its testing position of 24E and at the current rate is expected to reach 26E on January 27th.

Brian

[SV8QG]

Very good news indeed, we have a month or so to prepare our setups. Actually I have to replace my disk with a bigger one and to change my old Techisat PCI card with a new DVB-S2.

[g3zgz]

eshail 2.jpg (322.15 KiB) Viewed 5033 times

I can pick up the telemetry beacon from the sat on 10706MHz using just a 50cm offset dish, a .1db LNB and my SDR dongle.
It's about 25db above the noise floor.

I don't know how the signal level of this beacon will compare to those on the amateur transponder but at least it's a start.

I also have fed my scanner receiver set to Narrow FM and used this to adjust the dish for maximum quieting on the signal.

With my DRO LNB, if I leave it on for 30 minutes or so the oscillator drift is very little and a SSB signal may be resolvable with a little difficulty!

The top image shows a zoomed in scan (the grey area in the centre is a 3khz bandwidth setting.

Now to follow ES-HAIL as it moves to 26E and get a bigger dish!

Dave

G3ZGZ

eshail.jpg (318.35 KiB) Viewed 5033 times

[g4hiz]

Considering the satellite movement. If you look at N2YO.com, which has 'live' tracking data, you can see that the altitude is less than the nominal Geostationary one (roughly 35786km) and at the time of writing was noticeably decreasing with each minute. The effect of this is to increase the orbital angular velocity (by conservation of momentum) and the satellite will appear to move to the East relative to those at the nominal altitude. This orbital manoeuvre may explain why there is currently Ranging tone added to the Ku Beacon at 10706MHz, which can be seen as the 16kHz tones either side of the carrier in the picture above.
Since the satellite has only been launched just over a month, I would be surprised if the IOT has been completed already, for a satellite of this complexity, one would expect several weeks at least. Hence, they may only be adjusting the orbital position slightly, possibly to mitigate interference to/from their testing. Only time will tell.
73
Jen G4HIZ

[g0mjw]

There is an assumption of a manoeuvre, it might be the opposite. If you don't do station keeping the satellite will start to follow a figure of 8 and slowly drift East or West, depending on it's orbital location. This will save fuel and if it happens to drift in the right direction, bonus.

Mike

[G4EWJ]

Would you expect it to be moving faster if it really were going to 26E? Five weeks seems a long time.

Is there an exclusion zone around each satellite that it has to avoid as it moves past?

Brian

[g0mjw]

Maybe - depends. I don't think there are exclusion zones as such but there will have been an assessment to ensure no possibility of collision, including what to do if control of the satellite was lost. You certainly don't want to move a satellite quickly when it has deployed its solar panels etc. These are very long and delicate structures that can only deploy in micro-gravity. Any acceleration forces need to be very small. 25E to 26E doesn't sound far, but it's 700km or so requiring a ΔV of 1 km/h.

[G4EWJ]

Sounds like an interesting topic for a CQ-TV article. The satellite doesn't appear to be going anywhere at the moment after all. It's showing as 24.175E at the moment.

Brian

[g4hiz]

Looks like the satellite is moving. At this rate, it could be on-station by the end of the first week in January.

73 Jen

[g3zgz]

Looks like it has got almost to the rights spot (not that I know this for sure, just guessing).

see https://www.n2yo.com/?s=43700

Shows it at 26.49 degrees this evening.

Does anyone know how to interpret the figures on N2YO web site?

Happy new year from Dave G3ZGZ.