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This page calculates all the setting angles - azimuth, elevation, skew (aka polarisation tilt, polarisation angle), rotor tilt - to indicate where, in what direction, to point a satellite TV or Sky dish. It can draw a direction marker on an internet map, or calculate Magnetic Variance (aka Magnetic Declination) for use with a compass, or Grid Variance (aka Grid Convergence, Grid Angle) for use with a printed map.
If some of the terms or techniques mentioned here are unfamiliar, you are advised particularly to read other pages in this series before use, most particularly the General Introduction - see also the navigator bars at the top and bottom of the page, and the list of useful links below.
If you are unsure of the format for entering data, hovering the pointer over the field's label will bring up a short message describing the format expected. In general:
When you are satisfied with your settings, you can save them by pressing Submit and then bookmarking, marking as a favourite, the resulting URL, the parameters in which will recreate your original settings in the calculator. You may wish to do this once you have positioned a map exactly on your dish site as described below (though you will then have to wait for everything to reload).
The correct non-standard skews for the Hot Bird and Astra satellites, respectively +3.5 & +7.5°, are given, accompanied by yellow warning text - hovering the pointer over the field will display an appropriate message, including the standard skew normally expected.
Clicking on a map button fixes latitude and longitude as the method of designating the dish location, and creates a map with a marker and azimuth line for aligning the dish. Dragging the marker to a new location recentres the map(s) and updates the calculator. Likewise, changes in the calculator will where necessary be reflected in the map(s).
For worldwide locations, the Google map has four choices of base layer selectable by clicking the buttons in the top right hand corner. Satellite pictures take significantly longer to load, so it's quickest to use Map to get as close as possible to the intended final location and zoom level before switching to Satellite or Hybrid. If you plan to print the map, please read the Notes.
For locations in the UK, there is also an option to create an Ordnance Survey map, which will automatically select appropriate calculator settings for itself to work correctly (these won't impair the Google map if you create both). For aligning a satellite dish, Ordnance Survey on-line coverage of most parts of the British Isles, even St Kilda, is good to very good, excepting parts covered by other agencies: Northern Ireland (low scale) and Channel Islands, Rockall, and Eire (non-existent). If, despite the coordinate vetting, you manage to create a map of somewhere not actually covered, the map may just show nothing, or stick on an area on the north east coast, in which case ignore it and use the Google one. Coordinate conversion between Lat/Lon and E/N doesn't use OSTN02™, so coordinate readouts should only be considered accurate to around 5m.
Satellite images are often subject to perspective distortion to an extent significant in the context of aligning a satellite dish, thus making their results potentially less reliable than the initial impression given by their appealing simplicity. I recommend working entirely from ground level - position the marker at the point on the ground beneath the proposed dish siting, and choose as aiming point a landmark the base of which is crossed by the line.
Apologies for these inconveniences.
Useful links (no endorsement of external sites intended and nor responsibility taken for their content):
Many thanks to: