GB748761A - Improvements in or relating to circuits using cold-cathode scaling tubes - Google Patents

Abstract

748,761. Electronic counting apparatus. NATIONAL RESEARCH DEVELOPMENT CORPORATION. April 7, 1953 [April 8, 1952; Sept. 19, 1952; Feb. 17, 1953; Feb. 23, 1953], Nos. 8914/52, 23557/52, 4366/53 and 4990/53. Class 106 (1). A scaler or counter comprises a cascade of stages each including a cold-cathode scaling tube (47, 48) and an associated gate (45, 46), a pulse generator 40 providing a transfer pulse at its output for each input pulse, a connection 42 for feeding the transfer pulse to all the gates in parallel, means for causing each input pulse to open the gate 45 associated with the first tube 47 and means for causing a transient output condition arising in a preceding tube coincidently with a transfer pulse, to open the gate associated with the immediately succeeding tube so that the transfer pulses are utilized to drive those scaling tubes having their associated gates in the open position. In a preferred embodiment the discharge normally rests on one of the B cathodes of the tubes 47, 48. An input pulse, Fig. 1 e, at terminal 44 is applied to the trigger of a cold-cathode tube 45 and also causes the pulse generator 40 to raise the potential on line 42, Fig. 1 g, thus causing the tube 45 to fire. The potential on line 41 may also be raised at this time, Fig. 1 f, but, in another embodiment, line 41 is normally held at the higher potential. The higher potentials on the A and B cathodes drive the discharge onto the next K cathode; then, as the generator 40 causes the potential on line 41 to fall sharply, Fig. 1 f, the discharge passes to the next A cathode. Finally, the potential of line 42 is brought back to normal, Fig. 1 g, causing the discharge to move to the next B cathode and thus registering the addition of one unit. When the rise of potential on line 42 drives the discharge onto the zero cathode Ko an output pulse, Fig. 1 h, is developed across a resistor 49 which serves to trigger the gate tube 46 of the next decade almost simultaneously with the input pulse, Fig. 1 e, causing the carry. The positive rise in potential on line 42 is maintained long enough to allow for a succession of carry-overs to pass through all the counter stages. In another version the discharge rests normally on an " A " cathode and each input pulse causes a rise in potential of line 41 followed by a rise on line 42. Other types of multicathode counting tube can be employed. Specifications 680,466, [Group XL (c)], and 748,950 is referred to.