The Shore Effect

Author: J.B. Hoag

If the radio waves pass along the shore of a body of water, their slightly higher velocity over the water than that which they possess over the land causes them to be bent shorewards. The error which this introduces into radio direction finders is shown in Fig. 34 K.

Fig. 34 K. An explanation of the "shore" effect

The same trouble is encountered among the valleys and peaks of mountainous country. The use of transmitters operating on the higher frequencies, say 125 MHz (= 2.4 m wave-length), helps. These short waves are not as much subject to bending or refraction as the longer waves.