Patent GB-740041-A (GB)
Title: Telegraph transmitting apparatus
IPC: A24D1/16
Filed: 1954-03-23
Abstract: 740,041. Code telegraphy; thermionic distributers. TELETYPE CORPORATION. March 23, 1954 [April 15, 1953], No. 8459/54. Class 40 (3). In telegraph apparatus for the continuous transmission of permutation code signal elements which are applied to a set of electron tubes successively conditioned to transmit the code elements over a channel the final permutation element is first applied to a storage device and subsequently transferred to the corresponding electron tube so that all the permutation elements of a succeeding signal can be applied to the apparatus as soon as the next-to-the-last permutation code element has been transmitted whereby the transmission of the succeeding signal can be commenced immediately after the transmission of the previous signal has been concluded. On application of potential to the anode 41 and grid 47 the left-hand side of the triode 42 conducts and positive potential at cathode 48 is applied to the grid 53 of tube 35 which is conditioned for firing. The pulses from a generator 56 are applied to the grid 59 of the right-hand side of the triode 42 which conducts momentarily, and a positive pulse from its cathode is also applied to the grid of tube 53 which fires and over resistor 43 makes the left-hand side of triode 42 non-conducting. Operation of distributer. The next positive impulse from the generator 56 again makes the right-hand side of triode 42 conductive and a positive impulse is applied to the grids of the tubes 35 ... 40. As the tube 35 is conducting a somewhat positive impulse is applied from its cathode 62 to the grid 76 of the tube 36 which fires and the resulting fall in anode potential is applied to the tube 35. A capacitor 77 connected in parallel across resistor 63 opposes change in the potential of cathode 62 at the instant that the anode potential of tube 35 drops, and a capacitor 81 connected across resistor 79 tends to hold the cathode 78 of the tube 36 at ground potential. With cathodes 62, 78 at relatively high and low potentials respectively, the tube 36 is fired and the tube 35 is quenched. The remaining tubes 37 to 40 are fired in succession on the successive application of positive impulses over the conductor 61 in response to the pulses from generator 56 to the grid of the triode 42. When the tube 40 fires, the potential of its cathode is applied via junction point 51 and conductor 52 to the grid 53 of the tube 35 which is thereby conditioned for the subsequent cycle. Transmission of signal impulses. When tube 35 fires, the rise in cathode potential is applied to the grid 20 of the valve 23 and if a marking impulse is applied over conductor 12, the left-hand side of the valve conducts and the fall in potential renders the left-hand side of valve 69 non-conducting. The relative fall of the cathode potential makes the right-hand side of valve 69 conducting and the coil 71 is energized to move the armature 72 to the marking condition. The fourth impulse is applied over conductor 15 to the cathode 26 of the right-hand side of the valve 22, and if it is a mark, the valve does not conduct when the positive impulse is applied to the grid 87 from the tube 38 and the left-hand side of the valve 69 remains non- conducting to send a space. Similarly for the fifth signal element applied to the cathode 27 of the left-hand side of the valve 28. When the tube 39 fires a positive pulse is applied to the grid of the left-hand side of the tube 28 and also to the grid of a thyratron 31 of which a grid 30 is already controlled by the sixth signal element applied over the lead 17. If this element is a mark, the tube 31 fires and remains fired until either its anode potential is lowered or its cathode potential raised so that the code condition on the lead 17 can be removed. When the tube 40 fires in its regular sequence a positive impulse is applied over lead 94 to the grid 95 in the right-hand side of the tube 28, and if the tube 30 is fired, i.e. the sixth element is a mark, the potential of cathode 33 will be relatively high and the left-hand side of the tube 69 will remain conducting to send a spacing element to the line 10. When the tube 35 fires in the subsequent cycle the rise in potential at its cathode 62 is applied over lead 98 to the grid 99 of a valve 101 which conducts and applies a reduced potential to the anode of the tube 31 which is quenched and conditioned for operation during the subsequent cycle of the distributer. Specification 670,761 is referred to.