WIRELESS IN A NUTSHELL.

Dunstan Times, Issue 3134, 11 September 1922, Page 8

WIRELESS IN A NUTSHELL.

You can understand' the whole working of wireless by means of a simple experiment conducted with two corks floating at opposite end's of a bath. Touch one of'jthein with your linger. It bobs up and down a few times, audi as it docs so ripples, or small waves, liegin to course outwards from it in all directions. Tlie next second', cork number two bobs up and down in exactly the same way as number one did. The waves set up my the action of the first cork have reached it and caused it to make similar movements. Now imagine a very long bath, ai each end of which is a person provided with a floating cork, whilst a partition prevents them from seeing each other. The two can easily arrange a code ol' signals made by the bobbing of the corks, for each persons knows that be can make the oilier man's cork behave exactly as bis own does. In the case, of the two corks Ibe signals are transmitted by small visible waves which pass through water. They do not travel at a great rate, and the eye can follow their movements quite easily. .hist the same thing, except thai Ihe waves are bigger and quicker, happens in wireless. The man who is sending either Morse signals or actual words ihrough the wireless telephone causes his transmitter to send' out trains ol waves which agitate not water, or even air. but an invisible medium known as ether, which exists everywhere. To do this he uses an instrument which conveys groups of waves to a high wire, called the aerial. The aerial is Ins cork. It bobs up and down as the waves reach it. and in doing so sends them out far and 1 wide in every direction. . . The man who is receiving the message must also have an aerial, which is suspended in the ether, just as a cork is suspended in water, and receives it from the transmitting station. Each jolt corresponds to one thrown out by the sender, and the result is that the two wires, even if they are thousands of miles apart, vibrate in unison. Wireless waves are so huge and so rapid that they have no effect upon the eve or ear'. Every wire that is stretched in the air is vibrating day and night in response to wireless signals unless you have some device that will reduce these vast waves to something that the ear can take in. The strength of wireless waves is less than a millionth of the power that works an ordinary electric bell. A butterfly's wings, make a thousand times more noise than these wonderful waves as they pass through the air! The wireless receiver is so delicate that even this tiny amount of power causes it to vibrate. And it is so arranged that it can receive wireless waves surging up and down perhaps ;U)00,0(K) miles a second, and reduce their speed until they come within the range of the human ear. which is insensible to vibrations more rapid than 1.3,000 a. second.

The speed reducer may fake the form of a hard piece of crystal, or ol' a wonderful electric valve. This valve can also fie used to magnify sounds ol' any kind to many thousand times their real loudness.

In tin- wireless telephone the vibrations set up by the speaker's voice are transformed at the transmitting end. Their short, slow-moving waves are turned into long ones of enormous rapidity, which are cast abroad from the aerial. At the receiving end they are reconverted, so that when they pass into the 'phones they reproduce exactly the sounds made by the sender.