GB923597A - Improvements in apparatus for recording and repeating telephone messages - Google Patents

Abstract

923,597. Substation equipment. J. FEAT. July 21, 1960 [July 23, 1959; July 11, 1960], No. 25494/60. Class 40 (4). [Also in Group XXXVIII] In a magnetic drum type recording and playback apparatus for a substation, the actions of record, off and playback via the telephone receiver are controlled by a single switch while a pointer rigidly attached to a combined record playback head indicates the amount of unused drum remaining. The normal baseplate of a desk set is replaced by the base 2 (Fig. 2), contact plates 3, 4 being connected to line and plate 5 to the normal cradle switch, a spring-loaded flap 7 connecting plates 3 and 5 together when the set is not placed on the recorder. Flexibly mounted plates 15, 16 and 17 co-operate with plates 3, 4, 5 respectively under the influence of magnets 6 and 21. With key 47 in the recording position, thus lighting indicator lamp 13a, ringing current pulls up relay 24 (Fig. 3) which closes circuits for a motor 31 and a power supply unit 26, consequently spindle 34 starts to rotate and an R-C coupled transistor amplifier 30 is energized. Arm 42 (Figs. 10, 11, not shown) of a function switch 38 (Fig. 7, not shown) begins to rotate in the direction of the arrow (Fig. 3) and a contact staple 41 bridges a first pair of conducting tracks 40 so energizing a vibrator 25 in place of the normal bell set. Upon the bridging of the next two pairs of conducting tracks, the output signal from a reading head 43, which scans a magnetic track 39 containing a prerecorded message is applied via a conducting band 44 and spring 45 to the amplifier 30 and hence to the calling subscriber. Finally, arm 42 is restrained by a stop 42a and it slips on spindle 34 whilst closing suitable circuits for the recording of a message on drum 35. A raised thread 36 on this drum serves to guide recording playback head 57 which is connected to an erasing head 62 although both heads can rotate independently about an earthed guide bar 53. When the caller replaces his receiver, relay 24 falls back, the power supply and motor are cut-off and arm 42 returns to its initial position under spring action. If the recording head reaches the end of the drum then a set of contacts 63 are operated and no further calls can be recorded until the drum is reset. When key 47 is placed in the neutral position, heads 57 and 62 are lifted off the drum by the action of rod 56 and are returned by spring pressure to their initial position. Moving key 47 to the playback position causes stud 50 to ride up face 51b of frame 52 and consequently rod 56 is rotated slightly with respect to rod 53 which is fixed rigidly to the chassis 22, thus allowing playback head 57 to rest upon the drum but preventing erasing head 62 from doing so. At the same time switch wafers are operated so that the telephone earpiece can act as an output transducer. The recorder may be powered by batteries and the motor may be a clockwork one which is provided with an electrically triggered start and stop device.