word recogniser and delayed trigger

Ext. Trig. Word Rec. Ext. Trig. 5V •o 4 76consists of two four bit binary comparators, IC1 word recogniser and delayed trigger Many oscilloscopes are not particularly suitable for displaying digital signals. A simple and regularly repeating pattern is easy enough to display, but signal patterns with a very low repetition frequency of 50 Hz or less can prove to be very difficult to examine. This circuit rectifies this problem in two ways. Given a normal trigger input, an inexpensive oscilloscope can be provided with features usually only found on the dearer types with a dual timebase. This extension circuit is useful for both analogue and digital signals. The second part of thecircuit is an 8 bit word recogniser, which can be extended if or more further comparators in series with pi input required. This can be used to determine the trigger buffers will also have to be increased. The timebase delay circuitry consists of two monostable multivibrators, MMV1 and MMV2. The actual time...