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Terrain between TQ476218 (10 m a.g.l.) and Heathfield, TQ566220 (antenna 256 m A.O.D.)

For best broadcast TV and radio reception, you should have an unobstructed path between your TV or radio aerial and the transmitter. The yellow and pink lines should not have any ground impeding them. The yellow line is the radio line-of-sight path and is the most important. If the yellow line is unobstructed but the pink line is you may get some multipath/ghosting on analogue TV. (DTT and DAB are less affected by this.) Red sections indicate ground that is obstructing your line-of-sight (yellow) path. If you want to know what it is, hover the mouse over the red section you should see a six-figure Ordnance Survey grid reference of the obstruction. You can then locate it on an OS map to find out what it is, or click on the red section of the chart to open Streetmap in a new window to see the point and a small area around it.

Terrain does not take into account local issues such as trees and buildings - watch out for trees if installing in winter.

Raising the height of your TV aerial is the main option you have to improve your reception. That is, of course, usually the most difficult thing to do. For safety's sake you should really use an aerial installer for roof aerials.

Site parameters
Base ngr of TQ476218
Base height is 62.7 m above sea level
Base aerial is 10 m above ground
Distant station NGRTQ566220
Distant aerial AOD 256 m above sea level
Distance between stations 5.6 miles (9 km)
beam heading of distant station90

the pink line shows the boundary of the first Fresnel zone. Obstructions in this region weaken the signal by diffraction.

view a map of area between TQ476218 and TQ566220

back to terrain form

 

Selecting and siting your TV aerial

Aerial system components

Why DTT is different from an analogue install

 

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Megalithia home


terrain program adapted from G4JNT, PHP charting from Lars Magne Ingebrigtsen M E g A L i T h i A
Text and photographs ¤ RM 1992-2008 unless otherwise credited
version 0.96 Tuesday March 19 2024 09:50