GB721060A - Improvements in or relating to pulse counting circuits comprising electron tubes - Google Patents

Abstract

721,060. Cathode-ray tubes. TELEFONAKTIEBOLAGET, L. M. ERICSSON. Aug. 8, 1952 [Aug. 15, 1951], No. 20064/52. Class 39 (1) [Also in Group XIX] In an electron valve for counting electrical pulses which contains a cathode, control electrodes, one or a number of anodes connected together, and a magnetic field which causes movement of the electron beam when a voltage pulse is applied to the anodes, the deflection of the beam across two or more control electrodes by one pulse is prevented by the arrangement of condensers in the electrical connections to the control grids or a supply to the control grids of a voltage pulse which is of opposite phase to that applied to the anode. A tube 22, Fig. 3, contains a cathode 21, control electrodes 1, anode 11 and an axial magnetic field to rotate the beam from one space adjacent a control electrode to the next when a voltage pulse is applied to the anode through the transformer 28. Two or more deflections caused by the internal capacities 31 are prevented by condensers 51. The time taken to deflect the beam from one space to the next can be adjusted by a voltage proportional to and of opposite phase to the voltage pulse through a condenser 61, Fig. 4, to the control electrodes 1. The number of pulses can be measured by fluorescent indications on a screen in the tube. A counter 22, Fig. 5, a number of which can be connected in series, has control electrodes 1-10, anode 11 and magnetic field 23. Negative pulses are supplied to the terminals 26, 27 and are led over terminals 73, 74 to the next counter tube. An amplifier contains condenser 78 and resistances 79, 80 which damp out positive pulses and also negative pulses of less than a predetermined peak voltage so that the selected negative pulses are fed to the grid 81 of the amplifying valve 76 which feeds the positive pulses to the oscillator 77. Negative pulses of predetermined duration and voltage are supplied through the triple wound transformer 28 to the terminals 73, 74 and to the anode 11. Series connected counters can be pre-set by a pushbutton switch. Resistances 82 are used for adjusting differences in the tube characteristics. Specification 675,465 is referred to.