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An explanation of motor polar axis angle, declination offset angle and dish elevation setting for H-H DiSEqC Motor - Theory.
Example: Moteck DiSEqC Motor SG2100A
Site Latitude of 52 Degrees
Polar axis angle calculation will be: 90 – 38 = 52, so scale on the fixed bracket set to 52 or elevation scale on other side to 38 (90 - 52 = 38). Dish elevation calculation – first find the declination offset angle, in this case 7.5° (which is the declination angle for a latitude of 52 degrees) so 30 (angle of this motor shaft bend relative to the main polar axis) minus 7.5° = 22.5, therefore 22.5° is the angle you should set on the dish scale as a starting point for your due South satellite.
Other manufactured DiSEqC motors may have the stub arm cranked forward by various angles, including for example 40 and 46.5 degrees.
It should also be noted that some dish elevation brackets are not that accurate and above is for info only as a rough starting point. Once the dish has been set up with an alignment meter on your due South satellite, the declination offset would have already been made and will be near enough correct for tracking the arc
Example: Moteck DiSEqC Motor SG2100A
Site Latitude of 52 Degrees
Polar axis angle calculation will be: 90 – 38 = 52, so scale on the fixed bracket set to 52 or elevation scale on other side to 38 (90 - 52 = 38). Dish elevation calculation – first find the declination offset angle, in this case 7.5° (which is the declination angle for a latitude of 52 degrees) so 30 (angle of this motor shaft bend relative to the main polar axis) minus 7.5° = 22.5, therefore 22.5° is the angle you should set on the dish scale as a starting point for your due South satellite.
Other manufactured DiSEqC motors may have the stub arm cranked forward by various angles, including for example 40 and 46.5 degrees.
It should also be noted that some dish elevation brackets are not that accurate and above is for info only as a rough starting point. Once the dish has been set up with an alignment meter on your due South satellite, the declination offset would have already been made and will be near enough correct for tracking the arc
