Post by Forum Admin on Jul 23rd, 2012 at 3:46pm
`I've marked where your location is on the map below:
It is hard to spot your location in the small scale map.
The accuracy of the map is somewhat uncertain and as the satellite is not fixed in space the beams wobble about a bit. I would expect you to see different receive measurements during the day for such a beam edge site location. The beam edge is quite steep and even small satellite pointing error causes significant changes in level.
There are four (*) N.Africa beams which seem somewhat larger than the standard beam (like the Algeria beam). I suspect that the red contours refer to further out contours of the beam and that the larger size is a result of assuming that a downlink carrier for sites like yours is set up with a bit rate, modulation and coding to suit 1.2m dish sizes at well beyond the blue contour. The blue line is the limit for the "standard" package and you are well outside this blue line. Something special may be necessary for you. Has your service reseller contacted Skylogic to get something special set up for you ?
You seem to be just on or outside the red line for 120cm dish + 4 watt (Shaped service and different pricing).
For Ka band (20/30 GHz) the surface accuracy and solid metallic surface quality of your 1.2m dish will be very important. 1mm (1/10th wavelength) is the maximum distortion allowed and is difficult to achieve with a 1.2m dish.
I don't know what your dish looks like. If it is a standard Ku band dish it may not be suitable.
A problem with many dishes is that the weight of the feed/radio assembly pulls down on the two side struts attached to the dish and distorts the dish shape. You can check for dish distortion by putting tight sewing thread or fishing lines up/down and across the front face. They should just touch in the middle. Ref: https://www.satsig.net/pointing/rear-side-struts.htm Less than 1mm gap is needed.
Very slight damage to the dish, stress due to uneven tightening of 4 bolts attaching it to the rear hub, or pulling on the sides due to side struts will ruin the gain.
The dish shape must be treated with great delicacy !
I am presuming the focus (distance from feed to lower edge of the dish) is correct. If the focal distance is adjustable and therefore could be wrong, read the dish assembly instructions carefully.
If the dish shape is perfect and you still don't get a good enough signal then I guess that you are simply too far from the beam centre.
(*) The "Benghazi" beam does not appear to be available for Tooway service. Sold to the military or to TV company or repointed to Iraq have all been suggested.
Best regards, Eric.
It is hard to spot your location in the small scale map.
The accuracy of the map is somewhat uncertain and as the satellite is not fixed in space the beams wobble about a bit. I would expect you to see different receive measurements during the day for such a beam edge site location. The beam edge is quite steep and even small satellite pointing error causes significant changes in level.
There are four (*) N.Africa beams which seem somewhat larger than the standard beam (like the Algeria beam). I suspect that the red contours refer to further out contours of the beam and that the larger size is a result of assuming that a downlink carrier for sites like yours is set up with a bit rate, modulation and coding to suit 1.2m dish sizes at well beyond the blue contour. The blue line is the limit for the "standard" package and you are well outside this blue line. Something special may be necessary for you. Has your service reseller contacted Skylogic to get something special set up for you ?
You seem to be just on or outside the red line for 120cm dish + 4 watt (Shaped service and different pricing).
For Ka band (20/30 GHz) the surface accuracy and solid metallic surface quality of your 1.2m dish will be very important. 1mm (1/10th wavelength) is the maximum distortion allowed and is difficult to achieve with a 1.2m dish.
I don't know what your dish looks like. If it is a standard Ku band dish it may not be suitable.
A problem with many dishes is that the weight of the feed/radio assembly pulls down on the two side struts attached to the dish and distorts the dish shape. You can check for dish distortion by putting tight sewing thread or fishing lines up/down and across the front face. They should just touch in the middle. Ref: https://www.satsig.net/pointing/rear-side-struts.htm Less than 1mm gap is needed.
Very slight damage to the dish, stress due to uneven tightening of 4 bolts attaching it to the rear hub, or pulling on the sides due to side struts will ruin the gain.
The dish shape must be treated with great delicacy !
I am presuming the focus (distance from feed to lower edge of the dish) is correct. If the focal distance is adjustable and therefore could be wrong, read the dish assembly instructions carefully.
If the dish shape is perfect and you still don't get a good enough signal then I guess that you are simply too far from the beam centre.
(*) The "Benghazi" beam does not appear to be available for Tooway service. Sold to the military or to TV company or repointed to Iraq have all been suggested.
Best regards, Eric.