Hawkins electrical guide ... : questions, answers & illustrations : a progressive course of study for engineers, electricians, students and those desiring to acquire a working knowledge of electricity and its applications ; a practical treatise (1914)
Hawkins, N. (Nehemiah), 1833-1928 · New York : T. Audel & Co. · leaf 90
3 or 5 listening key. Effect: In any case the main instrument would be cut off by anopen line and not by a short circuit for which the strap is used. Ifopen or crossed listening key contacts be on an unstrapped key,the plan of wiring would work wrong and become confused. 90. Listening key contacts… … TRANSMITTER 1
Electrical engineering
Internet Archive · Brigham Young University · Public Domain Mark 1.0. Free to use for anything.
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