- Will it make any difference if this antenna is mounted on the side of the tower, about 4 ft away from the tower, pointing out with the elements vertical, instead of on top of a tower?
- Will it make any difference if this antenna is mounted on the side of the tower, about 4 ft away from the tower, pointing out with the elements vertical, instead of on top of a tower?
They usually recommend to have an antennas elements 1 wavelenght from other objects. That's 6 feet at 150MHz, so I wouldn't think it would make much impact on the antenna at 4 feet. Any metal behind an antenna changes the directivity depending of the wavelenght distance.
You could probably have one of the elements 1/4 wavelenght from the tower to increase signal strenght but sacrifice it at other frequencies.
- Will it make any difference if this antenna is mounted on the side of the tower, about 4 ft away from the tower, pointing out with the elements vertical, instead of on top of a tower?
Omni X antenna antenna needs to be mounted vertical on a horizontal arm, aka side mount. As Ubbe mentions the antennas elements 6 feet at VHF away from the tower would be the minium lenth for the side mount. That will still put the Omni X elements too close to the tower which will distort the antennas reception pattern. Not to mention the torque on the side mount from the wind.
Here is a picture showing the approximate radiation pattern for side mounting a vertical antenna. This chart has distance of the antenna from the mast horizontally along the bottom and the diameter of the mast or tower on the left side vertically.