CODE KEYBOARD

摘要

This keyboard may be used when there is the need to give one or two signals for a correctly typed combination. It simultaneously records two complementing code combinations. The keyboard contains triggers, one per digit of the code, and schemes for formation of a single impulse - one per trigger - to whose inlets one randomly selected button is connected. The outlet of each trigger is connected to the permit inlet of the scheme for formation of a single impulse of the subsequent digit, while the outlet of the last but one trigger serves simultaneously as an outlet of the code keyboard and is connected through a delay chain and scheme OR to the triggers' nullifying inlets - less the last one - where the last trigger serves as memory of a correctly typed additional code.