How to direct and align dish in Saudi Arabia ?

Hi, I'm seeking help on to what direction I need to direct my dish and how to align it.
I have iDirect 3100 and I should aim to NSS 6.
My location is in Saudi Arabia, eastern province near Jubail city.
Latitude: 26.6 N
Longitude: 49.9 E

Apprciate your urgent help and support.

Thank and regards,
CzAinAb

Thanks. I did calculated the direction. But I'm afraid that the way I assembled the BUC and LNB to the feedhorn is not correct ? since I'm not getting the signal with my site meter ?!
is there any guide for assembling BUC & LNB using Chanel Master dish.

Thanks again and appreciate any help.

Hello, I've sent several pictures for my dish assembly also please find em here as well.
Appreciate your usual upmost help.

Missing 6 images.

Regards.

Thanks for the great help. I will try it out and keep result posted.




Thanks & regards.

Well done.

A point of clarification: you say that the feedhorn is in the direction of the yellow line. I think you mean that you have rotated the feed assembly so that the LNB is on the yellow line. This means you are receiving the downlink polarisation called "vertical" and have made an adjustment of -57 deg anticlockwise.

The polarisation needs to be adjusted to 1 deg accuracy and this is why the NOC asks you to make adjustments. When you do this you need to crouch low down at the side of the antenna and adjust the rotation of the feed assembly with your arms underneath it. You must not have any body part between the feed horn and the dish or obstruct the beam towards the satellite. If they ask you to turn the feed 5 deg, do so and then wait. It may take the NOC 30 seconds to get a good reading, similarly after the next adjustment. They are trying to talk you into the middle of a very narrow and deep null, where making the measurements is difficult.

Regarding loss of signal.

You may not have had the dish pointing tightened up properly and accidentally jogged it a little in azimuth or elevation. Having found the satellite it normally takes 10 - 20 minutes of further adjustments to find the exact beam centre. This is important since the transmit beam is narrower than the receive beam. Tightening the nuts tends to mispoint the dish. When you finally tighten the azimuth clamp, the elevation will typically rise slighty and need readjusting.  Another reason for loss of signal may be that your F connectors are loose. The F connector centre pins should stick out 2mm and should properly insert into the socket holes. The connectors must be covered with self amalgamating tape or similar to keep out moisture.

The bottom of the mount legs should be held fixed with small rawl-bolts or fixed to the concrete in some way.

Rotating the polarisation by 5 deg will make little difference to the wanted co-pol signal as the peak is very broad. You need to rotate by a much larger angle, like 15 to 45 deg to get a noticable reduction in signal level. If there is no signal on the opposite polarisation then a 45 deg rotation will only produce a 3 dB reduction. This is why polarisation is best pre-set approximately by calculation. If you try to do it by measurement you need to wrap a strip of paper round, and degrade the signal substantially one way. Mark the paper and note the exact degraded quality(volts in your case).  Rotate the feed on the opposite side of the max and find the exact same degraded level. Mark the paper and halve the distance. Repeat several times and average the centre point is necessary. You can see why it is a lot easier to let the NOC make cross-pol measurements and talk you into the null.

Regarding possible obstruction of the beam. You can get an approximate idea by putting your eye behind the dish, in the middle, at the lower edge and sighting along the line of the feed support arm. If this goes well above the obstruction, then fine. If it is marginal a more accurate method it to sight 32 deg elevation with an inclinometer at the height of the bottom edge of the dish. An inclinometer made with an A4 size card, a length of cotton thread and small nut is fine. Just mark a line at the required angle using a protractor or using the tan calculator at Start, Programs, Accessories, Calculator, View, Scientific on most PCs.   tan=opposite/adjacent.
If you attach the inclinometer card to a long strip of wood, one person can look along it while another reads the angle.

Best regards, Eric

Transmitter isolation is a product of your polarization angle; POL or SKEW or TILT, whatever your hardware provider calls it.
Assuming that you were provided a dish of sufficient gain and a properly working transmitter of adequate power, an insufficient isolation number generally suggests inaccurate pointing angles. The error is primarily in the polarization angle, but is related to Az and El as well. Did you try to rotate the feed while in contact with your NOC?

Another cause could be insufficient EIRP. Perhaps Eric can, but I'm unable to ascertain the transmitter power from the photos. It looks like a 1w unit, but I can't be sure. Even the dish could be too small, but generally provider-supplied hardware should be specific to the application.

At any rate, I believe 30 only represents threshold - and you're still 12 points shy of that. By threshold, I mean don't think the job is done when you get to 30. Keep peaking pointing angles until you can conclude there's no more improvement to be obtained. I have a 74cm dish and a 1w transmitter, and achieved an isolation figure of 39.

//greg//

1.2m and 3w should be enough for most any consumer-grade access. Installation issues aside, pointing your type of antenna is done in a particular sequence.
1. set in rough AZ/EL/POL angles from the look angle calculator
2. adjust AZ/EL to obtain received signal level from assigned transponder
3. optimize AZ/EL for peak RSL
4. test isolation, rotating feed as directed by the NOC.
In some cases, slight adjustments to AZ/EL may be required to optimize POL. In these instances, it's cost-effective to trade off some RSL points for an increased isolation number

It's also important to note that signal level adjustments will generally lag the physical angel adjustments by 10 seconds or more. Move the dish a few millimeters at a time, waiting for a new RSL to register each time.

If none of that works, it then may be time to consider incorrect assembly or defective hardware. Oh, and I don't see any indication that your system is grounded.

//greg//

Hi,

If I'm left with vendor I might be alone ... but with you guys and your support I will never be. Thanks for all and for all recommendations and advises. Unfortunately, I will be away from this site in a biz trip for 15 days. I shall be back on November 12th and get you my response.


Regards.

1.2m and 3watt is much more that enough in Jubail, NSS6 has a good coverage over Jubail, with 0.96m it can work also very well, trust me i lived in Dammam and installed in it 1.2m for NSS6 and it was much more than enough and very easy to point the antenna, it was easy like pointing to Nilesat, beleive that, your problem should be either in the cables or the configurations, or pointing, reveiw it man for once and it shall be solved,

It is very usefull to use Signal Meter, mmmm am trying to get you a technichan i used to deal with, or oyu can go to any at King Saud Street and get one with his TV receiver, when he gets a very good signal, ask him to wait and check the signal with your iDirect, then if it's good try to do CW, if the problem that your NOC can't see you, then i guess you should check your BUC and.


ALSO it is very important that you have the correct GPS values (Alt, Lat, etc), not all the modems have the same Gps coordinates formats, iDirect it's different than Nera, than link start etc, and make sure you gave your ISP the correct GPS (If they Asked for it), your GPS coordinates  should be taken using GPS device, not google earth or any website, try to take the GPS next your dish and write down the values.


Also it couldbe from the tower i faced this issue with a tree before, as i can see from your picture it's not difficlt to move yor antena it's not big tripod out there.



Best Luck