The Fading Characteristics of the Top-Loaded WCAU Antenna

The electrical characteristics of the original "guyed cantilever" antenna in use at WCAU are reviewed. Fading characteristics taken at several points in the service area are shown and analyzed. Probability considerations are used to place the fading phenomena on a quantitative basis. Model tests are described which led to the use of a capacitive area at the top of the tower. This capacitance consists of a set of outriggers insulated from the tower. The outriggers are then connected to the tower through an inductance. The first hat so constructed was found to be too large for good suppression of fading. The hat was reduced in size until a desirable condition was reached. Analysis of fading records, as well as listening tests, shows that the primary night service area is more than doubled and is now practically the same as the day service area. This has been accomplished with no increase in power and only a slight increase in ground signal.