GB1133036A - Distortion system - Google Patents

Abstract

1,133,036. Telegraphy. ATLANTIC RESEARCH CORP. 29 Nov., 1966 [31 March, 1966], No. 53294/66. Heading H4P. An arrangement for producing distorted telegraph signals comprises a logic circuit fed by the signal to be distorted both direct and via a delay, and by a signal representing the required degree of distortion. A telegraph combination to be distorted is set up manually on switches 26, Fig. 1, or a preset sequence of such combinations is derived from a store, and is passed in serial form to the logic circuit 10 both directly and via a ¢-bit delay, under the control of clock pulses which are also passed to the logic circuit. The clock pulses are derived from a counter 14, the output of which pulses the nine contacts of a selector switch 34 in sequence, first in one direction and then in the other. This switch selects the degree of distortion to be introduced in the code combinations, and so feeds to the logic circuit two pulses in each bit period, equi-spaced about the bit centre by an amount representing the distortion. Circuits are described for delaying or advancing the mark-space transitions, Fig. 5 (not shown), and the space-mark transitions, Fig. 4 (not shown), relative to the Stop-Start transition, which is never distorted. Delay or advance is selected manually. Alternatively, alternate code combinations in a sequence may have the transitions advanced and delayed respectively. In a further embodiment, Fig. 6 (not shown), all four forms of distortion are produced in turn automatically.