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Worse still was uplinking to a satellite which is in inclined orbit, so tracing a figure of 8 in the sky from earth.
If your dish has tracking facilities, then that makes it easier, but not all do.
A colleague once spent an entire England international football match staring at the spectrum analyser and very very gently nudging the dish in (hopefully) the correct direction, knowing if he got it wrong millions of viewers would notice!
Inspector Sands

It's quite spooky to stand under the dishes at Chilworth, their beam-width is obviously so narrow they have servos that constantly nudge the beam back towards the satellite as it drifts around in space (within its 200 (?) mile 'box')

Yes, that's tracking and its done in one or a combination of 3 ways:
1) By having a beacon receiver which is constantly monitoring the signal level of the satellites beacon (an unmodulated carrier on the satellite). This is reported to the dish controller, if the signal gets lower then the dish moves, tentatively left, right, up and down to see which one improves the signal.

2) by memory, after a while of doing the above the controller software learns where the satellite will be over the course of a day

3) by using data sent out by NORAD about the position of satellites

With big receive dishes the difference between a tracked and non tracked dish can be significant. If it drops out of tracking you soon notice the signal level drop

The orbitnof a satellite is predictable over a short period but issue if you've an adhoc dish you might not point it at a certain satellite for months and when you do the prediction data is out of date so it has to start building it up again
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The beacon receiver method is the one that ad hoc use tends to go for, and I have heard of where it has gone wrong.
This one was in Australia, where the beacon receiver was doing the tracking fine, until the time of year when the sun outages occur came along.
The beacon receiver then kept the dish on pan on the strongest signal, which by now was the sun.
Tracked it all the way apparently!
Inspector Sands

I am aware that even the big ground stations have been wiped out with storms, so if a 6m or even 18m dish can lose a signal, the difference between those you can mount on a truck (between 1.2m and 2.4m) is not going to be a major factor.

At Sky's uplink site at Chilworth they constantly watch the met office radar scans for trouble. They have a back up site not too far away, but far enough away that it shouldn't be affected at the same time by the same storm !

The issue with that is how good and quick your systems and procedures are at switching between the two sites. Really heavy rain enough to take out a major uplink site doesn't last that long, it can be that by the time you migrate your services the rain had improved where you are. Then you might have to do it again if it goes past your backup site

Maybe Sky can do it fairly quickly, cutting one and switching on the other with little delay. It would require a phone call to Astra too.

The thing with rain fade is that it's not the rain above you that's the issue it's what's in the distance where the dish is pointing that is. Having a good view in that direction is handy
I believe that Sky's switching between the two sites is almost instantaneous, and is tested fairly frequently (as it should be!)
I believe that Sky's switching between the two sites is almost instantaneous, and is tested fairly frequently (as it should be!)

Sky can also use their dishes on the roof of Sky Studios at Osterley too.
That sounds like a bit of a harsh question, but I am somewhat intrigued. Why did anyone think a third truck was a good idea?

The third truck apparently had more power capability and was due to swap with one already on site. However it couldn't arrive until late afternoon.

There was a microwave link to BT Tower installed after the first show, though it was compromised by the line-of-sight issues mentioned above.
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thegeek Founding member
Is there still a microwave link from the roof of the Albert Hall to the roof of BH, (or has there ever been one ?)

We did a recent OB from there with an SHF link to the Tower, but I think that may have been from a BT van. More or less the same direction though I suppose!

In the old days it would have been a link direct into Crystal Palace, but all that masthead receive infrastructure was torn out years ago.

Or into Television Centre East Tower as Chris Evans did from Riverside every Friday ... Sadly ???? The tower is no more ...
Sands, you're mentioning NORAD there, do you get given TLEs for the bird you're after?
Inspector Sands
Sands, you're mentioning NORAD there, do you get given TLEs for the bird you're after?

To be honest I don't know, it's an option on dish control software but I've never worked somewhere that's actually used it, mainly because control networks are normally kept away from the Internet

I'm sure someone will know, I suspect its more for non-inclined and non-geostationary satellites
Sands, you're mentioning NORAD there, do you get given TLEs for the bird you're after?

Isn't NORAD a Santa tracker?

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