Without going into and discussion of the merits (or lack thereof) of the antenna in question:
The default (mandatory) polarization for North American TV broadcasting is horizontal. A substantial number of US broadcasters have, or are planning to add as they go through repack, a vertical component to their signal that is said to improve reception for indoor antennas.
The power of vertically polarized signal can be some fraction up to 100% of the horizontal component and is phase shifted by 90 degrees. The resulting signal is either then circularly polarized (100%) or elliptically polarized (<100%). The additional polarization certainly isn't free. A station running a million watts horizontal would also have to run another million watts vertical (2 million watts total ERP) through an appropriately designed antenna. Doubles their transmitter electricity consumption as well as the expense of the second transmitter, the phased combiner, the antenna, etc.
When it comes to antennas that are supposed to be "omni-directional", it's my conclusion that they receive equally poorly in all directions since they have no capability to focus on anything. In multipath-prone areas, they're going to be the first to fail. In very simple locations with widely scattered towers, they usually do okay for short to medium range applications.
Last edited by ADTech; 21-Aug-2019 at 8:25 PM.
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