Some newbie questions about a USALS system in Greece

[David00]

Hello,

I’m planning a motorized satellite TV system for a property in southern Greece. This is to receive FreeSAT type content, in English mainly. The dish will be on a north-west facing wall clear of obstructions.

Have read about USALS and think I understand what it does – which is to point the dish at satellites who locations are stored in the receiver, as “offsets” to a reference point established at the outset.

Is there a way to get a motorised dish/receiver combo to do a blind search to locate all visible satellites when commissioning the system? So that I end up with a list of all the satellites the dish can see. I know most of these should already be stored in a USALS receiver. Time isn't an issue.

Once the system in operational, and I select a channel which causes USALS to position the dish, is there a way for the receiver to instruct the motor to hunt a little (a fraction of a degree perhaps) from the stored position, so as to find the optimum signal strength, and then update the stored position? Just in case high winds have changed the dish alignment slightly.

I'd welcome suggestions on a suitable dish/motor/receiver combo. I can go up to 1m in dish size, but then there's the wind... I’m reasonably technical, but not to the extent of hacking a Linux-based box, for example. Mid-range budget – whatever that is.

Thanks, David.

 

[ozumo]

A north-west facing wall isn't going to be ideal, try the Dishpointer website to see which satellites are visible from your intended antenna location.

Most receivers will allow you to scan all stored satellite locations in one go but the dish/motor will need to be correctly aligned beforehand - assuming that, all channels found will be listed by satellite or in one single list depending on how you wish to organise the channels, switching between the two options is usually a simple task.

With USALS you can edit the longitude setting to tweek all saved dish positions in one go.

 

[Mickha]

You don't hack a Linux based receiver, you just load a compatible image on it, and then play around with it to load various software, that you want to use.

USALS is easy to setup, you simply find out your Latitude, and Longitude, positive Longitude readings = East, negative = West.
You input these into your receiver, then send your dish/motor, which should be setup at 0, via your receiver, to a suitable satellite to align to, usually one close to your Longitude.
Providing the pole is secure, and plumb, the dish should find the available satellites, as the receiver should calculate where they are located, by using your Altitude, and Longitude, as a starting position.

You then fine tune the dish/motor, by sending it back to the satellite you aligned on, then adjusting the dish/motor brackets, to get your motor/dish to track the satellite arc correctly.

 

[David00]

A north-west facing wall isn't going to be ideal, try the Dishpointer website to see which satellites are visible from your intended antenna location.

Most receivers will allow you to scan all stored satellite locations in one go but the dish/motor will need to be correctly aligned beforehand - assuming that, all channels found will be listed by satellite or in one single list depending on how you wish to organise the channels, switching between the two options is usually a simple task.

With USALS you can edit the longitude setting to tweek all saved dish positions in one go.

@ozumo Thanks for the guidance. Since seeing your reply I've learnt a lot more about this topic, and will site the dish in a better location.

 

[David00]

You don't hack a Linux based receiver, you just load a compatible image on it, and then play around with it to load various software, that you want to use.

USALS is easy to setup, you simply find out your Latitude, and Longitude, positive Longitude readings = East, negative = West.
You input these into your receiver, then send your dish/motor, which should be setup at 0, via your receiver, to a suitable satellite to align to, usually one close to your Longitude.
Providing the pole is secure, and plumb, the dish should find the available satellites, as the receiver should calculate where they are located, by using your Altitude, and Longitude, as a starting position.

You then fine tune the dish/motor, by sending it back to the satellite you aligned on, then adjusting the dish/motor brackets, to get your motor/dish to track the satellite arc correctly

@Mickha Thanks, nice summary.

 

[Channel Hopper]

A north-west facing wall isn't going to be ideal, try the Dishpointer website to see which satellites are visible from your intended antenna location.

Most receivers will allow you to scan all stored satellite locations in one go but the dish/motor will need to be correctly aligned beforehand - assuming that, all channels found will be listed by satellite or in one single list depending on how you wish to organise the channels, switching between the two options is usually a simple task.

With USALS you can edit the longitude setting to tweek all saved dish positions in one go.

Is the system bolted to the wall but looking over it ?

 

[Terryl]

One additional note, the dish, motor and LNB should be aligned to due South (180 degrees true) at your location first....Motor set to its Zero position, and dish aligned to it. Otherwise your motor will be or could be off by several degrees.

Dishpointer dot com has an app to help with this.

 

[David00]

Is the system bolted to the wall but looking over it ?

There's nothing there yet. But I can and will fix it to a south facing wall. I'd assumed from the Astra 2 coverage map that the satellite was somewhere above Europe, and that I could just point my dish at it. But now know that it is above the equator so as to be geostationary, with the UK spot beam tightly focused on the UK. I'm too far outside the coverage area to get UK channels.

 

[Channel Hopper]

There's nothing there yet. But I can and will fix it to a south facing wall. I'd assumed from the Astra 2 coverage map that the satellite was somewhere above Europe, and that I could just point my dish at it. But now know that it is above the equator so as to be geostationary, with the UK spot beam tightly focused on the UK. I'm too far outside the coverage area to get UK channels.

Yes, most spots will be like a torch beam, concentrated on an area in western Europe (not all of them though)

Astra 2G at 28.2°E - LyngSat Maps

Astra 2E at 28.5°E - LyngSat Maps

Astra 2F at 28.2°E - LyngSat Maps

If you fit a large enough dish however........

 

[Terryl]

You might be able to get something on those satellites with a 2 meter sized dish (or larger) as most of the spot beams are not that closed in and that sharply focused, there is some back scatter off the antenna shrouds on the satellite.

Try a site called..Satbeams

You will be able to see whats going on with the signal beams for those satellites, just click on your location and move the marker to the nearest signal couture, this will give you an estimated antenna size for that location, if you move the marker to the next higher couture you will see the approximate dish size change, this would give you an ideal on what may be needed to get a signal at your location.

The old estimates (things may have changed over the years) for the size of the dish needed, was for every 1 dB of signal gain a 3 inch increase in dish size is needed.

In te charts listed by Channel Hopper, you will see a table for the EIRP/dBW (signal strength) to antenna size, it ends at the 41 dBW couture but shows the dish size needed for that couture, you can estimate from there.