| 摘要 |
1,142,975. Ripple control transmitters; generating oscillations. ELECTROMETRE S.A. 22 Sept., 1967 [30 Sept., 1966], No. 43195/67. Headings H3B and H4R. In a ripple control system for signalling the values of consumption meters over an electric supply network, a capacitor 3, which is charged through diode 5 to the peak value of the supply voltage, is discharged through a coil 2 by the semi-conductor controlled rectifier when a control pulse, having a precisely defined phase relative the supply voltage, is applied to the gate electrode 6 of the S.C.R. from the control circuit 9. In order to maintain the conduction of the S.C.R. irrespective of the length of the control pulse, feedback is provided from the coil 2 to the gate electrode via coil 13, the feedback maintaining conduction until the damped oscillation produced by the discharge through coil 2 drops below a predetermined value. In an alternative arrangement two S.C.R.'s are connected in series, with feedback via respective feedback windings, in order to reduce the voltage rating required of the S.C.R.'s, Fig. 2 (not shown).
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