Patent GB-940962-A (GB)
Title: Improvements in or relating to telephone station apparatus
Inventor: JONES ARTHUR FREDERICK
IPC: H04M1/274
Filed: 1961-02-28
Abstract: 940,962. Automatic exchange systems. GENERAL ELECTRIC CO. Ltd. Feb. 22, 1962 [Feb. 28, 1961], No. 7296/61. Heading H4K. An arrangement for setting up frequently wanted connections comprises a magnetic record which bears characteristic markings to determine the impulse trains and an impulse generator which sends impulses to the line and to the magnet driving the record. As shown, the record consists of a disc 6 with, for example, 50 concentric tracks which is rotated step-bystep by a magnet 8. Contacts 11, 12 are closed when the disc is off-normal. The apparatus is controlled by a number of keys, KC, KE, KR being of the locking type and KD, KS of the non-locking type. In order to record a number, the transducer head 7 is moved above a vacant track and key KR is actuated followed by start key KS. The number is now dialled, and the stepping magnet 8 receives trains of impulses from the impulse springs 27 of the dial. At the conclusion of each train when the disc 6 is stationary, as indicated by the steady lighting of lamp 35, key KD is actuated to energize the transducer head 7 to make a mark, and the disc advances one more step. After the last digit is dialled, key KD is actuated twice to make two consecutive marks. On the return of key KR the disc is advanced to normal by impulses from a self-interrupting relay D controlled by a shunt capacitor 31. In order to erase a recording, key KE is actuated followed by KS. The transducer head 7 is energized in the reverse direction and the disc 6 steps through a complete rotation. To send a recorded number over the line, the transducer head 7 is moved above the appropriate track, the handset 29 is lifted and, after dialling tone is heard, key KS is actuated. Relay D generates impulses which pass to the line and also to magnet 8 to step the record disc, the handset being shunted out when it moves off-normal. When a mark on the record is reached, a pulse induced in the transducer head 7 after amplification energizes relay A, which connects up relay B in place of D and advances the disc one step. Relays A, B are controlled by shunt capacitors 38, 36 to fall back slowly, and impulsing is resumed after a suitable inter-train pause. At the end of the recording where two consecutive marks are encountered, the second one causes the energization of relay C, which prevents reoperation of relay D and makes a self-stepping circuit for magnet 8. Cancelling key KC serves to return the record disc to normal and prevent any transmission of impulses meanwhile. In order to check a recorded number a counter may be provided instead of or in addition to lamp 35, and means may be provided for reproducing the number without sending impulses to the line. Instead of a disc the record may take the form of an endless tape which may be either a plain loop or a Mobins strip with a number of parallel tracks extending longitudinally. Mechanical means may be employed for shifting the transducer head 7 to co-operate with a particular track, for example, under the control of pushbuttons.