Short-term instabilities in either the amplitude or phase of a signal, particularly the signal on a cathode-ray tube. It has the effect of causing momentary displacements of the image on the screen, giving it a shaky or ‘jittery’ appearance. An oscilloscope that is used to measure the amount of jitter is termed a jitter scope. Momentary errors of synchronization between the scanner and receiver in television or facsimile transmission can cause jitter of the received images. This type of jitter is known as jitters.
In hi-fi sound reproduction systems that use a digital recording method, jitter can cause unwanted audible variations in the pitch of the sound output. These can be quite unpleasant. In compact disc systems, for example, a noise similar to ignition interference is heard. Jitter in digital recording is the equivalent of wow and flutter in a system using analogue recording.