Improvements in or relating to circuit arrangements for separating electric signal pulses

Abstract

Abstract 491,728. Television ; type printing telegraphy. WHITE, E. L. C. March 10, 1937, No. 7062. [Class 40 (iii)] Pulses of long duration (e.g. frame synchronizing signals) are isolated from a mixture of pulses of long and short duration, by applying the mixture to two parallel paths, one of which comprises a delay network, so that on combining the outputs, the delayed and undelayed long pulses overlap to produce a signal distinguished by amplitude which is isolated by an amplitude filter. In the Figure, the two paths comprise valve 3, and delay network 7 and valve 4; the outputs are combined and the oscillator 5, operating as disclosed in Specification 402,629, is biassed to be controlled only by the derived pulses of greater amplitude. The delayed and undelayed pulses may be applied to the anodes of a double diode, Fig. 4 (not shown), or to the grids of a double triode, Fig. 5 (not shown), or may be applied to the two control grids of a hexode valve biassed to pass current only when both grids are energized, Fig. 2 (not shown) ; in this case, the mixed signals may also be developed in the output by a triode portion.of the hexode energized with the undelayed pulses. The invention is applied to television, the multiplex signalling system described in Specification 470,495, and typeprinting telegraphy. Specifications 420,391 and 455,375 also are referred to.

Inventors

No inventors recorded.

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