Specifications for the multiplex printing telegraph system : theory and operation (1920)
Western Union Telegraph Company · [New York?] : The Company · leaf 76
Fig. 3 12. A switch is also provided in the base of the transmitter by means of which thecircuit through the feed magnet may be opened. This switch is shown in the transmittercircuit diagram, Figure 4.
Telegraph
Internet Archive · Northeastern University Library · Public Domain Mark 1.0. Free to use for anything.
