Patent GB-244025-A (GB)
Title: Telegraph signalling systems
IPC: H04L25/42
Filed: 1924-08-07
Abstract: 244,025. Western Electric Co., Ltd., (Western Electric Co., Inc.). Aug. 7, 1924. Automatic telegraphs; curbing at transmitter; systems using code elements distinguished by polarity of current.-In order to correct signals of varying length from an automatic transmitter, the signals are received from the transmitter by a distributor and are stored, regenerated and sent to the line as impulses of uniform length through the distributor bv a plurality of groups of relays, the relays in each group co-operating to form the impulses of uniform length. Fig. 1 and Fig. 2 on the right thereof show a complete transmitting system with four relay groups. Contacts 66, 67 of an automatic transmitter of the type described in Specification 241,327 are connected to the ring 68 of a receiving section A of the distributor and signal impulses are sent by means of the brush 69 and the segmental ring successively to windings 70 and 71, 72 and 73, 74 and 75, 76 and 77 of the respective groups of relays. Each pair of the windings is in mutually opposite directions. The restoring section B of the distributor comprises a continuous ring 78 connected to grounded battery 79 and connected successively by a brush 80 through a segmented ring to windings 81 and 82, 83 and 84, 85 and 86, 87 and 88 of the successive groups of relays, which windings are in the same direction. The segments of transmitting section C of the distributor are connected to the respective armatures 91, 92, 93 and 94 of the lower relay in each group. A curbing section D is also provided on the distributor comprising a ring 89 of section C, a segmented ring the odd and even segments respectively of which are connected togther, a grounded ring 96, and ring 97 connected to the cable 98. The segments of each ring correspond in number with the teeth in the tape feed wheel. The operation of transmitting takes place in four steps, the brushes 69, 80, 90 being displaced one segment as shown. In the first step a signal is set up on group 1 of the relavs, group 2 is restored and group 3 transmits to the cable. In the second step, group 2 receives, group 3 restores and group 4 transmits, and so on. The normal position of the armatures is shown in group 2 on the Figure, the relays being polarized from battery 146 over windings 147 - - 154. A dot signal positions the armatures as shown in groups 1, 3 and 4. The relays close locking circuits for themselves from the batteries 102, 103, 113, 117, 124, 128, 135, 139 over windings 110, 112, 121, 123, 132, 134, 143, 145 and the armature contacts. In the position. shown in the Figure a dot signal previously set up on the third group of relays is sent to the transmitting section C of the distributor by the connection of negative pole of battery 128 through contact 131 and armature 93 to segment 3 and by brush 90 to continuous ring 89 and to ring 95 of the curbing section D, the positive pole of battery 124 being connected to ground through contact 126. Brushes 99 and 100 of this section are fixed in the relation to one another shown, whilst brush 101 is adjustable. When brush 99 is entering on an odd segment, brush 101 with the adjustment shown will be on the mid-position of an odd segment and the circuit will be completed from ring 95, through brush 99, segment 3, segment 25, brush 101, ring 97 to cable 98. When brush 99 reaches the midportion of segment 3, brush 101 will be on segment 26 and cable will be grounded through brush 100 and ring 96. This corresponds to 50 per cent curbing.