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_.

WAVES, ELECTRIC.--Electromagnetic waves set up in and transmitted by and through the ether.

Continuous. Abbreviated C.W.--Waves that are emitted without a break from the aerial. Also called _undamped waves_.

Discontinuous.--Waves that are emitted periodically from the aerial.

Also called _damped waves_. Damped.--See _Discontinuous Waves_.

Intermediate.--Waves from 600 to 2,000 meters in length.

Long.--Waves over 2,000 meters in length.

Radio.--Electric waves used in wireless telegraphy and telephony.

Short.--Waves up to 600 meters in length.

Wireless.--Electric waves used in wireless telegraphy and telephony.

Undamped.--See _Continuous Waves_.

WIRELESS TELEGRAPH CODE.--See _Code, International_.

WIRE, ENAMELLED.--Wire that is given a thin coat of enamel which insulates it.

WIRE, PHOSPHOR BRONZE.--A very strong wire made of an alloy of copper and containing a trace of phosphorus.

WIRED WIRELESS.--Continuous waves of high frequency that are sent over telephone wires instead of through s.p.a.ce. Also called _line radio communication; carrier frequency telephony, carrier current telephony; guided wave telephony_ and _wired wireless._

X'S.--See _Static._

ZINCITE.--See _Detector._

WIRELESS DON'TS

AERIAL WIRE DON'TS

_Don't_ use iron wire for your aerial.

_Don't_ fail to insulate it well at both ends.

_Don't_ have it longer than 75 feet for sending out a 200-meter wave.

_Don't_ fail to use a lightning arrester, or better, a lightning switch, for your receiving set.

_Don't_ fail to use a lightning switch with your transmitting set.

_Don't_ forget you must have an outside ground.

_Don't_ fail to have the resistance of your aerial as small as possible. Use stranded wire.

_Don't_ fail to solder the leading-in wire to the aerial.

_Don't_ fail to properly insulate the leading-in wire where it goes through the window or wall.

_Don't_ let your aerial or leading-in wire touch trees or other objects.

_Don't_ let your aerial come too close to overhead wires of any kind.

_Don't_ run your aerial directly under, or over, or parallel with electric light or other wires.

_Don't_ fail to make a good ground connection with the water pipe inside.

TRANSMITTING DON'TS

_Don't_ attempt to send until you get your license.

_Don't_ fail to live up to every rule and regulation.

_Don't_ use an input of more than 1/2 a kilowatt if you live within 5 nautical miles of a naval station.

_Don't_ send on more than a 200-meter wave if you have a restricted or general amateur license.

_Don't_ use spark gap electrodes that are too small or they will get hot.

_Don't_ use too long or too short a spark gap. The right length can be found by trying it out.

_Don't_ fail to use a safety spark gap between the grid and the filament terminals where the plate potential is above 2,000 volts.

_Don't_ buy a motor-generator set if you have commercial alternating current in your home.