Electricity experimentally and practically applied; a book for the beginner and for the practical man, principles, experiments, practical applications and problems (1910)
Ashe, Sydney Whitmore · New York, D. Van Nostrand company · leaf 58
ecure sufficient mag-netic effect. The resis-tance of the relays istherefore great, beingfrom 80 to 300 ohms.The resistance of thesounder is much lessand may be anything from 5 to 20 ohms. To send a mes-sage the operator waits until theline is clear, and then he opensthe short-circuiting switch on… … Fig. 59. — Sounder.
Electricity · Electrical engineering
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
