Three types of mounts are commonly used with TVROs. These are:
Fixed mounts. In this case the dish cannot be repointed so it must be pointed at the desired satellite as part of the assembly process. It would be a popular option for a spherical dish, or larger parabolic antennas where it was desired to only view a single satellite. Arguably this type of mount can be made more rigid and will be less likely to move during high wind.
Az/El mounts. This type of mount is popular for installations where there is only one satellite of interest and there would only be a rare requirement to repoint the dish to another satellite. Az/El mounts are relatively simple to manufacture, assemble and point. However, moving the dish to a new satellite requires changes of both the azimuth and elevation of the dish. But the variations are reasonably obvious and the initial assembly of the dish is not difficult.
Polar (or equatorial) mounts. These type of mounts are able to point at different geostationary satellites by making a single adjustment to the mount. However they require more mechanical precision than Az/El mounts. It is also essential that the mount be carefully aligned to true north (not magnetic north) during initial assembly otherwise the dish will not track the polar arc correctly. This type of mount is well suited to the addition of motorised drives to allow users to relocate the dish to different satellites by remote control.
Figure 11: Az- El and polar antenna mounts [Ref 5].
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