. The Bell System technical journal . g, so as to alwaysproperly load the radio transmitter, and incoming so as to give theshore subscriber the best received volume. A voice-operated deviceknown as the vodas provides means for suppressing echoes and sing-ing. This device is essentially the same in principle and in its operationas those used in intercontinental service which have been described indetail in previous publications. In addition to the above units ap-paratus for monitoring and testing is provided. The harbor station, moreover, is arranged for remote control opera-tion, equipment bei
. The Bell System technical journal . g, so as to alwaysproperly load the radio transmitter, and incoming so as to give theshore subscriber the best received volume. A voice-operated deviceknown as the vodas provides means for suppressing echoes and sing-ing. This device is essentially the same in principle and in its operationas those used in intercontinental service which have been described indetail in previous publications. In addition to the above units ap-paratus for monitoring and testing is provided. The harbor station, moreover, is arranged for remote control opera-tion, equipment being provided so that the transmitter is automaticallyturned on when the operator inserts a plug in the Harbor Circuit jack. During operation the transmitter is continuously monitored bymeans of an auxiliary radio receiver in Seattle tuned to the transmitterfrequency. In addition, the two-way portion of the voice-frequency 1 For a description of the receiver see the followiiitr clijjest. HARBOR CRAFT SHIP-TO-SHORE TELEPHONE SERVICE 711. 712 BELL SYSTEM TECHNICAL JOURNAL circuit is monitored by means of an amplifier and loud speaker bridgedacross the circuit through a high impedance coil. This, of course, indi-cates to the attendant the general status of each connection as to trans-mission in both directions. Monitoring by means of a headset is alsoavailable and is usually resorted to in those instances where conditionsrequire close attention to the adjustment of the apparatus to insure asatisfactory connection. When a call originates on land, the toll operator connects the landline from the shore subscriber to the radio circuit, designated Harbor,by means of a regular toll cord circuit. This operation, which requiresthe insertion of a plug in the jack of the radio circuit, automaticallystarts the transmitter at Point Edwards. It also indicates to the radioattendant by means of an alarm that a connection is being made andthat his attention is required to ascertain whether any adju
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
