Page:February 1916 QST.djvu/5

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22
QST
FEBRUARY, 1916

appoint district headquarters and turn over to each of these the stations on their lines. Each district headquarters could then begin the work of developing the best stations. The rest would follow naturally, and if there are enough amateur stations in the

country to make relaying possible it would not be long before a practical Relay League would be established. Then we amateurs would have something of which we all could be justly proud.


APPARATUS ARRANGEMENT

By a League Member


A friend, thirty miles from my radio station, had installed a half kilowatt transmitting set, but was unable to communicate with me. He had been asking me to come out and look his station over; he felt quite sure that everything was O. K., but wanted me to suggest improvements. One snowy afternoon in December I took the ―― Railroad to his town which was located in the southern part of New York State. It was a one-horse town which boasted of a wireless station but no trolley cars. As my friend had no car, I was compelled to plow my way through no less than six inches of snow, but I finally reached his home and was no sooner inside the door than he unceremoniously dragged me off to see his set.

“Well, Brother, what do you think of this? I've got it arranged pretty nicely; haven't I?”

I gazed around and the first thing that attracted my attention was an oscillation transformer fastened on the ceiling. Two long, straggly wires came down from this to a condenser on the operating table. Six more straggly wires drew my attention to a porcelain tube in the floor. “Where do those go?” I inquired, pointing at the wires.

“Oh yes, that is a clever little idea of my own. You see, this plaguey rotary is such a confoundedly noisy affair that I put it down cellar with the transformer,” explained the genius.

“Yes! I suppose your aerial switch is on the roof so you can have it near the aerial," I snorted in disgust.

“Well, what's the matter, you old Grouch? Anyway, the receiving set is all right; isn't it?”

“Yes, because fortunately it's all 1n one unit and you didn't have a chance to scatter the instruments around as your fancy dictated. Of course, I suppose, if you had had the opportunity, you would have put the audion bulb out on the front door so that people might know you have a wireless station. But, all joking aside, I really believe I shall have to give you a short talk

on the fundamental principles of wireless,” I said, as I thought out my lecture.

“Ga, Ga, ―.―.” he signed.

“Well, in the first place, you have a condenser which is charged from your high voltage transformer. This condenser discharges through your rotary gap and primary inductance of your oscillation transformer. By adjusting the condenser and primary inductance, you can obtain your two hundred meter wave length.” (Fig. 1)

“Just how much condenser and inductance must I have,” broke in my listener.

Cautioning him about the QRM I remarked, “If you have twelve glass photograph plates, eight inches by ten inches, coated with six by eight inch tinfoil, and a loop of inductance about eight and one-half inches in diameter, you will get a two hundred meter wave. Now the object of this primary circuit is to stow up energy in the condenser and then make it flow through the inductance. The longer you make your inductance, the greater will be your wave. This means, if you have a great many long leads connecting the condenser, spark gap, and oscillation transformer, you will build up the wave and will lose energy in the long conductors instead of centering it in the primary of your oscillation transformer.

“Next, the primary inductance must readily give up its energy to the secondary, but the secondary must not re-act back on the