VOLTMETER.--An instrument for measuring the voltage of an electric current.
WATCH CASE RECEIVER.--See Receiver, Watch Case.
WATER-PIPE GROUND.--See Ground, Water-Pipe.
WATT.--The power spent by a current of 1 ampere in a resistance of 1 ohm.
WAVE, BROAD.--A wave having a high decrement, when the strength of the signals is nearly the same over a wide range of wave lengths.
WAVE LENGTH.--Every wave of whatever kind has a length. The wave length is usually taken to mean the distance between the crests of two successive waves.
WAVE LENGTH BAND.--In wireless reception when continuous waves are being sent out and these are modulated by a microphone transmitter the different audio frequencies set up corresponding radio frequencies and the energy of these are emitted by the aerial; this results in waves of different lengths, or a band of waves as it is called.
WAVE METER.--An apparatus for measuring the lengths of electric waves set up in the oscillation circuits of sending and receiving sets.
WAVE MOTION.--Disturbances set up in the surrounding medium as water waves in and on the water, sound waves in the air and electric waves in the ether.
WAVES.--See Wave Motion.