Page:Popular Science Monthly Volume 91.djvu/335

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Popular Science Monthly

��N, beside it, is the exact reverse, namely, dash-dot.

Having the six letters of the first two groups fairly well in mind, practice in word-formation should be begun. A num- ber of simple words can be formed from these letters alone, and they should be practiced until there is not the slightest hesitation in spelling out any word using these characters. In learning the Morse symbols the signals may be called by name at first, but it is well to accustom oneself to the corresponding signal sounds almost from the beginning of study. That is, instead of continuing to call M "dash dash" or "two dashes" the student should begin very early in his work to attempt to reproduce the sound of the signal itself. This may be done by whistling or hissing for short or longer times, representing dots and dashes, and so imitating as nearly as may be the actual sound of the wireless or buzzer signals.

Word Practice

Practice words, using the first six letters learned, are as follows:

��ATE

MAIN

TAME

EAT

TIME

EMIT

��NAME

AIM

AMEN

MAN

NEAT

MIEN

��TIE

MAT

MAIM

MEANTIME

TEAM

ITEM

��In spelling them in Morse, great care must be taken to give every dot and dash its full value of time, and particularly to space the letters properly. The space or idle interval between every pair of signals within the same letter is equal in length to the time of a single dot. The space between letters is longer, and equal to three dots (the time of a dash). At first it is a good plan to make the space between letters even longer, so that there can be no confusion. Even skilled operators oc- casionally run letters together to form "combinations" which are difficult to read and which often lead to errors in the trans- mission of messages. The space between words should be still greater, and equal to the time of at least five dots.

The thing to bear in mind constantly is that the operator receiving your message can not transcribe it correctly unless you form your characters correctly, and that you must consequently strive to make perfect signals built up of perfectly formed dots and dashes carefully spaced. Fig. 3

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shows the time-interval layout of the words NAME ITEM, with normal spacing be- tween signals, letter and words; in practice the spaces between signals within a single letter should not be longer than the dots,

���The proper method of connecting the key, buzzer and battery together on a circuit

but it is often well to exaggerate the spaces between letters and between words, for the sake of clearness.

Using the Buzzer

Before taking up the third and fourth groups of letters (Fig. 2), buzzer practice should be commenced. This will require a buzzer, a Morse key and one or two dry- cells. The key should be purchased rather than home-made, and should be of the regulation form with normal-sized key- knob, for the reason that the physical habits of key sending must be based on muscular practice. If one becomes accus- tomed to using an abnormally large or wrongly adjusted key, he will be handi- capped in the later use of the standard instrument. The key, buzzer and battery should be connected together, as shown in Fig. 4, when the buzzer, will sound con- tinuously so long as the key-knob is de- pressed and the circuit closed. The key should be screwed directly to the practice table, well toward the right and rear, so that the operator's elbow can rest on the table surface while he is sending. The distances must be selected so that the key-knob is within easy reach, and yet not so close that operation is cramped. It is important to fasten the key directly to the table top, without any sub-base which tends to lift the knob too high above the surface. A very good plan for the new student to follow is to call at some local telegraph office and see the actual arrange- ment of keys there used. The operators and office managers are usually glad to explain the key arrangements and the best way of holding the knob for sending, though one should of course not ask such favors during the busy hours of the day.

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