A Tower Antenna can be used if sufficient land is not available for a Symmetrical "T" Antenna. A portion of the top set of guy wires is used to form the top hat for this antenna.
A Tower Antenna is electrically inferior to a Symmetrical "T" Antenna of the same height due to the decreased top loading. Top loading serves two purposes; decreasing the input reactance and consequently the voltage on the antenna and increasing the effective height.
A 50 foot tower requires a plot of ground with a radius of 60 feet. Range over "good" ground varies from approximately 40 miles at 190 KHz to 50 miles at 535 KHz with a 50 watt transmitter and from approximately 60 miles at 190 KHz to 65 miles at 535 KHz with at 100 watt transmitter.
Used when space is limited.