Mounting A Satellite Dish Or Rotor

Page loading is staged  -  as soon as possible the calculator's form unlocks so that you can begin entering data, further options becoming enabled as the code to support them completes loading.  The options available also depend on the chosen receiver location as follows:

• Anywhere  -  Google Map displays a direction line for aligning the dish, while the calculator shows the true azimuth (degrees clockwise from True North), and another azimuth corrected either against Grid Variance (Grid Convergence, Grid Angle) for use with a printed map, or against Magnetic Variance (Magnetic Declination) for use with a compass.  As accurately as possible, enter locations for the receiver and satellite, click the map button, and if required drag the markers to a more precise location.

  The map has two choices of base layer selectable by the buttons in the top right hand corner.  Satellite pictures can 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.

  Satellite images are often subject to perspective distortion, often 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 simplicity.  Although it may seem counter-intuitive, you should work 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.

• UK Mainland Nations & the IoM  -  UK OS Map displays the azimuth on an Ordnance Survey map.

  Coordinate conversion between Lat/Lon and E/N doesn't use OSTN02™, so coordinate readouts should only be considered accurate to around 5m.

  OS's OpenSpace® on-line mapping covers UK mainland down to street level (other UK nations are covered by other agencies and are either only available via OS at low-scale or not at all).  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 Ctrl-Click the map button to remove it, and just use the Google one. 

If you plan to print either map, please read the Notes.

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 bar at the top of the page, and the list of useful links at the bottom.

If you are unsure of the format for inputting data, hovering the pointer over an input will bring up a short message describing the format expected.  In general:

• Latitudes, longitudes, grid and magnetic variances can be entered as decimal degrees or DD:MM:SS.  In both cases, southern and western values can be entered as negative or by appending S or W, northern and eastern as positive or by appending N or E.
• Other angles should be entered as decimal degrees.
• Time values for the Sun can be entered as 24 hour HHMM or HH:MM, or as 12 hour HH:MM AM or PM.  Seconds values will also be accepted and included, but most published calculations for the Sun are only given to the nearest minute, and greater accuracy than that should not be assumed.
• All other data such as grid references and post codes should be entered in their normal format.  Irish grid references should be flagged with a leading I.

UK Place Name look up covers UK mainland only.  UK Post Code look up should find codes for the entire UK, but to reduce the chances of usage capping by Google, does so by searching the OpenSpace UK mainland database first, only trying Google on failure.  Other post codes and places, for example Eire, can be looked up using the World Place Name option, but the database is very US-centric, so append an appropriate country name, for example ,Eire.

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.

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).

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 (direction) line for aligning it.  Dragging the marker to a new location recentres the map(s) and updates the calculator.  Likewise, where necessary, changes in the calculator will be reflected in the map(s).  After creating a map, changing settings other than receiver latitude & longitude, or choosing a different satellite, is not recommended and may not be possible.

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.

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.  Work 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.

For UK mainland nations, there is also an option to create an OS map.  OS's OpenSpace® on-line mapping covers UK mainland down to street level (other UK nations are covered by other agencies and are either only available via OS at low-scale or not at all).  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 Ctrl-Click the map button to remove it, and just 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.