American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 392
stead of an induction coil to set up the electromagnetic impulses, Mr. Preece employed a mo-tor-driven make-and-break wheel B,Fig. 2 54«, by which means a sharperrise and fall of current is obtained,which in turn has a more pronouncev.1effect upon the receiving instrument t.n^ u—^ ^ jg j^ii… … zm£7 S=i=^ iiajj fT7 335^ AMERICAN TELEGRAPHY. with this break-wheel give as good results at 3.3 miles as a 2^ horse-power trans-formed into alternating currents by a transformer, owing to the smoother sinusoidalwaves of the latter. \\hen key K is closed, the pulsations from b are transmitted tothe…
Telegraph
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer03inte-154-93.webp)
