American telegraphy and encyclopedia of the telegraph; systems, apparatus, operation (1909)
Maver, William, jr. [from old catalog] · New York, Maver publishing company · leaf 229
-I Polarized Rela^ … )4 ^y^ ^1 Cands^er Lt OOOOOQ 000000 P/ieosfat/ E POLAR DUPLEX TERMINAL CONNECTIONS, (GRAVITY BATTERY. to give an opportunity to readjust the armature to its proper place. As a rule, how-ever, a good, working static balance can be obtained on a polar duplex withoutgiving the armature of the…
Telegraph
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