In Fig. 185 is shown exactly the same arrangement, with the exception
that the talking apparatus illustrated in detail at Station A is that
of the Kellogg Switchboard and Supply Company. Otherwise the circuits
of the Dean and the Kellogg Company, and in fact of all the other
companies manufacturing harmonic ringing systems, are the [...]
Series and Multiple Connections. When a number of voltaic cells are
joined in series, the positive pole of one being connected to the
negative pole of the next one, and so on throughout the series, the
_electromotive forces_ of all the cells are added, and the
electromotive force of the group, therefore, becomes the sum [...]
A complete K.B. lock-out telephone is shown in Fig. 190. This is the
type of instrument that is usually furnished when new equipment is
ordered. If, however, it is desired to use the K.B. system in
connection with telephones of the ordinary bridging type that are
already in service, the lock-out and selective mechanism, which [...]
Great use is made in the design of telephone circuits of the fact that
the electromagnets, which accomplish the useful mechanical results in
causing the movement of parts, possess the quality of impedance. Thus,
the magnets which operate various signaling relays at the central
office are often used also as impedance coils in portions of [...]
