. Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems . £>_ rQCni Ringer ^ Shunt•^Imp. Cal/.Device r 3Cond. Cord. ^P , Red I C—i! 02 W Orange Call Device Fig. 148.—Wiring diagram for a wall telephone with an Transmitter Shunt Fig. 149.—Wiring diagram of a wall telephone with an extension. Figure 147 shows the circuit of a desk telephone of the direct-currentreceiver type just as the instrument is wired. Figures 148 and 149 show two different arrangements for connecting SUBSCRIBERS STATION EQUIPMENT 153 up a wall telephone with an extension so th
. Automatic telephony; a comprehensive treatise on automatic and semi-automatic systems . £>_ rQCni Ringer ^ Shunt•^Imp. Cal/.Device r 3Cond. Cord. ^P , Red I C—i! 02 W Orange Call Device Fig. 148.—Wiring diagram for a wall telephone with an Transmitter Shunt Fig. 149.—Wiring diagram of a wall telephone with an extension. Figure 147 shows the circuit of a desk telephone of the direct-currentreceiver type just as the instrument is wired. Figures 148 and 149 show two different arrangements for connecting SUBSCRIBERS STATION EQUIPMENT 153 up a wall telephone with an extension so that when either is called bothbells will be rung. Of course if an arrangement is desired whereby thebell will be used at one telephone only, the other bell is simply omittedfrom the circuit. ^ Figure 150 shows an extension circuitfor a desk telephone of the direct-currentreceiver type. When a third wire is not used betweena desk or a wall telephone and its extension,a biasing spring connected to one end of theringer armature should be utilized to pre-vent the bell of one of the telephones onthe line tingling when a call is made fromthe other telephone. By using this biasingspring the tingling may be stopped althoughit may be necessary to reverse t
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttelephone, bookyear19
