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American telephone practice (1905)

Miller, Kempster Blanchard, 1870-1933 · New York : McGraw publishing company · leaf 253

An illustration from American telephone practice, 1905, leaf 253
-ohm non-inductive resistancein the ground connection at the central office on the grounded linewas to prevent the dead grounding of the test rings so as to keeptheir potential above that of the earth when a connection was madewith the line so that the line would give the proper busy test whileso… … -f-iANW -UMJ qROUNPtp LINE

Telephone

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