Reply With QuoteWhy not have a go at it yourself?
What stage are you at... dish fitted and remote cabling run and positioner configured, etc?
Which suburb of Adelaide are you in?
C band
Currently have C band 1.8 non motorisedmounted and about to replace with a 2.3 motorised and was wondering if anyone can recommend someone to set angle adjudtment...last person that did it has moved from Adelaide
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Why not have a go at it yourself?
What stage are you at... dish fitted and remote cabling run and positioner configured, etc?
Which suburb of Adelaide are you in?
Once weather improves dish will be mounted and old one removed,,, actuator cable also will be run..Originally Posted by mtv
I am thinking I might try myself maybe I can try to replicate the position angle of existing dish by looking at old dish and alignment is easy with a meter but what confuses me is people talk about making sure it's at true north as to get full access to Clarke arch or something ?
In North of Adelaide ... Paralowie
Geostationary satellites are positioned around the equator.
A dish is centred on true north (as opposed to magnetic north, which continues to move slowly each year).
As the dish moves between east and west, it points highest at the top of the arc and lower the further it travels east or west.
The arc the dish follows is called the Clarke Belt and if the dish is aligned correctly, it will 'see' all satellites on the belt , other than those below the horizon or have a blocked signal path by obstructing objects... trees, buildings, etc.
Just because there is a clear path to a given satellite doesn't necessarily mean you'll receive signals from it, as the satellite antenna (transponder) has to be pointing in a direction that covers your location. This is called a 'footprint or 'beam'.
My avatar is a good example of how a motorised dish moves.
All dishes are different, so copying the settings of the fixed dish you have now will not work, as it will no doubt be aligned with a particular satellite and not pointing true north, so you will need to align a motorised dish from scratch.
Go to and enter your address and select True South / True North from the drop down list of satellites.
Using Google Earth, it shows an aerial view of your property.
Drag the marker to where the dish is installed and you will see a green line in the direction of True North... which is where the dish needs to point.
The latitude and declination figures are also displayed. You need to use these to angle the dish.
Note... all these settings are approximate and you will need to make adjustments, probably several times, to get them exact.
There's a tutorial for setting up a motorised C-Band dish .
Faceache (13-01-17),irritant (14-01-17),Rik van der Velde (02-01-18)
Oh ya ok thanks I will look at the links and looks like I will need to buy something so I can measure the angle correctly... thanks for the explanation it made more sense than any others I had read and will try to setup myself if no luck will try find someone but at least I know I tried lol
MTV so if I understand correctly from reading the tutorial you start buy pointing the dish towards true north, by the looks of tutorial picture if standing behind you would use your LNB to drawer an imaginary line towards true north ?
When setting the angle adjustments could you use just a simple angle finder ?
Correct, when the dish is centred on the pole, it should face true north as you've described.
Yep... that's all you need to use.When setting the angle adjustments could you use just a simple angle finder ?
Another fancy name for an angle finder is an inclinometer.
Another critical thing is the mounting pole must be perfectly plumb on all sides.
It's not critical for a fixed dish, but if it's out of plumb even a tiny bit, a motorised dish won't track the arc properly.
So seems I have a lot of work to do and before I pull old dish down I better check mounting pole if not plumb I may as well re mount elsewhere (less work).. I expect reason why you must face true north is that is the starting point for Clarke belt so your actuator then will allow dish to track full array of belt ?
Yes, if the dish mount isn't centred, it won't follow the arc correctly.... true north is the reference point.
You also need to check the existing pole diameter... does the new dish have the same size pole mount?
irritant (14-01-17)
I wanted to ask, true north from one's location happens to coincide with the highest point of the arc at one's location, is that right?
If you were located at say 156° E longitude exactly, then Optus C1/D3 would be located at true north for you, not so? Also the highest elevation of all your available satellites?
Could one use this principle to hone in on true north?
Last edited by irritant; 14-01-17 at 02:24 AM. Reason: Additional question
Yes, yes and yes.
irritant (14-01-17)
Remember that the entire dish mount can rotate on the mounting pole, so you have to align the dish on the mounting pole facing true north first.
Once you have that alignment correct, the dish will be at it's highest point of the arc.
irritant (14-01-17)
You may find this useful.........it tells you all you need to know, and then some.
The graphic down the bottom of the page showing the "dish to satellite arc" graphically illustrates how you are trying to match the travel arc of the dish to the Clarke Belt, where all the satellites live.
Just bear in mind that the tutorial is written for the Northern Hemisphere, so reverse any compass references given
Regards True North....when installing my 2.3m dish, I just deducted the Magnetic Declination for this area (around 11.5 degrees) from 360 degrees (result around 348 Magnetic) and then used a compass on that bearing to line up a reference point out front of the dish pole, and then set the dish mount up on that bearing.
The satellite gods were smiling that day, and it worked
Good luck.
Last edited by Thala Dan; 14-01-17 at 02:45 PM.
That's a very good guide, Thala Dan. The illustrations are excellent.
As Thala Dan has indicated, readers will need to note that the guide is written for the Northern Hemisphere, therefore terms relating to direction will need to be reversed for the those located in the Southern Hemisphere, i.e. substitute North for South and East for West etc.
irritant (14-01-17)
Setting up correct polar mount for many is a hit and miss situation. If you follow below steps your Polar Mount will be correctly set, track all available satellites every time.
1. You need a good angle inclinometer and a long straight edge. No Compass needed.
2. The mounting pole MUST be 100% plum otherwise polar tracking won't work.
3. Using the Actuator set the dish direction to be centered straight out with the mount, as if you are doing a straight AZ/EL setup.
4. In Adelaide set the main elevation to 54.4° from the horizon, lock it in and don't touch it anymore.
5. Set the declination to (minus)- 5° of the main elevation. Best to use a long straight edge on the face of the dish and set the angle to 40.6° on the straight edge (49.4° -90°) then lock it in and don't touch it again.
6. Using the actuator drive the dish to the west until 32.9° elevation is reached = 57.1° on the straight edge.
7. Loosen the pole securing bolts just enough so that the whole mount can rotate on the pole. Since the elevation is set 32.9° and given the pole is 100% plum, You should have no problem finding Asiasat 5 by panning to the west. Once you find it and optimize the signal secure the mount to the pole.
The next task would be to store the satellites on your antenna positioner.
Last edited by B52; 15-01-17 at 03:10 PM.
Ok so I believe that if mounting a dish to a pole on side of house to brick wall the following rules should apply
Up to 2.3m dish 1 metre above roof and size of dish 3m and above 1.5m ?
There's no ''rule' as such, you just need to ensure you have sufficient clearance 1. for the dish to move freely (if it's motorised) 2. the signal path must not be obscured by the roofline or other obstacles.... trees, walls, adjacent buildings, etc.
The shorter the support pole you can get to achieve the above, the better, to reduce wind loading.
Dishes above roof height may require a council permit. (that would be a rule)
irritant (04-02-17)
Thx again MTV now I have to just kick my brain into gear and work the clearance side of it out out... is there anyway of finding out the lowest sat position East and respective West ? That way I can see which way the dish will need to run and make sure it clears all obstacles etcThere's no ''rule' as such, you just need to ensure you have sufficient clearance 1. for the dish to move freely (if it's motorised) 2. the signal path must not be obscured by the roofline or other obstacles.... trees, walls, adjacent buildings, etc.
The shorter the support pole you can get to achieve the above, the better, to reduce wind loading.
Dishes above roof height may require a council permit. (that would be a rule)
Use dishpointer. (as per my post #4)
If you're lucky, you could get between 91.5 E Measat3 and 180 E IS 18
irritant (04-02-17)
Use... execlent tool.
irritant (04-02-17)
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