American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 203
__m- … Ym -=-B OPEK-CIKCUIT REPEATER. The theory of the open-circuit method of operating Morse circuits is shown inFig, 36. Normally, on these systems there is no battery to the line. AVhen it isdesired to repeat from one such circuit into another an arrangement theoreticallysliown in Fig. i38t/ is…
Telegraph
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