While this chapter is titled ‘digital’ some of the procedures described here may equally be applicable to analogue. As with Chapter 10, these examples of test and measurement are in no way intended to be definitive. There are others, either already in existence or likely to appear in the future.
Bowtie (see Figure 11.1) checks for equality of level and timing between component circuits. Lightning serves a similar function but uses a vectoral display of Y against Cb and Cr, and like bowtie it is a specialised test designed to give a quick appraisal of circuit conditions. But, whereas bowtie requires its own test signal to be sent, lightning makes use of colour bars.