Patent GB-190490-A (GB)
Title: Registering, (counting and/or measuring) telephonic conversations
IPC: H04M15/30
Filed: 1922-12-14
Abstract: 190,490. Freund, E., and Brociner, S. Dec. 15, 1921, [Convention date]. Metering systems. - When a connection has been established, the subscribers are given periodically-disturbed preliminary conversation facilities sufficient for the calling subscriber to ascertain the correctness of the connection, but not sufficient for a satisfactory conversation to be carried on. The disturbing means is cut out when the calling subscriber operates his meter or starts his time-recording device. The Figure shows the invention applied to a semi-automatic connection between two subscribers A, B. A relay G energized over its winding HG locks up over its lefthand winding and front contacts 3, 4 of the calling-subscriber's feed-relay E, and closes a circuit over interrupter U for ringing-relay R which periodically applies ringing-current to the line. When the called subscriber replies, feed relay F energizes but the ringing-current is not cut off and acts as a disturber. When the calling subscriber operates his metering key ZT, the b-lead is directly grounded, short-circuiting the relay E which unlocks relay G and frees the talking-circuit from disturbance. Alternatively, the disturbing means may be cut out by means of an alternating-current relay operated by current sent from the calling sub-station, or by a marginal relay which only responds to current exceeding a certain strength. The Specification, as open to inspection, under Sect. 91 (3) (a) comprises also arrangements. Fig. 1 (Cancelled), in which an additional alternating- current source is employed as the disturber, and a system in which a preliminary talking connection is severed after a short interval, unless the meter or time-recorder is operated. In the system shown in Fig. 1 (Cancelled), relay G energizes as before, and completes a circuit for ring- ing relay RR, ringing current being intermittently applied to the a-lead of subscriber B from generator RMI over primary coil Trp. When the called subscriber replies, feed relay F energizes, relay StR breaks the circuit of relay RR but disturbing current from the additional generator RMII is periodically superposed on the talking- circuit, until the operation of the calling-subscriber's metering key RK short-circuits relay E. thus discornecting generator RMII. The microphones M at the sub-stations A, B are shunted by choking coils CC. The circuit arrangements for a system in which the temporarily-established connection is broken down after a certain time interval if the metering key is not operated are similar to those shown in Fig. 1 (Cancelled), the generator RMII and interrupter MBII being replaced by a relay actuating a timed cut-out. In a modi fication, the disturbing source, which also serves for calling, and a time-restricting device may be situated at the calling sub-station and may be brought into operation by the calling subscriber sliding a bolt, the return of the bolt after the calling subscriber has replied, cutting-out the disturbing source and freeing the talking-circuit. Calls may also be recorded at the exchange by means of a printing device set in accordance with the wanted number as set up by the semi-automatic operator, and printed on a paper strip individual to the calling subscriber when the registering key is operated. In manual systems, the wanted subscriber is called by the operator, the calling subscriber being allowed a sufficient time during which he should actuate his metering apparatus, thus, either automatically or by signal to the operator, causing the cutting-off threat to be removed. This subject-matter does not appear in the Specification as accepted.