Frame, field, line, and sample rates
This chapter outlines the field, frame, line, and sampling rates of 480i video, 576i video, and HD.
The standard sampling frequency for component SD is exactly 13.5 MHz. This rate produces an integer number of samples per line in both 480i and 576i. HD standards at integer frame rates specify multiples of 13.5 MHz: 720p, 1080i30, and 1080p30 systems sample at 74.25 MHz. HD standards also permit operation at 1000/1001 times that rate.
Television systems originated with field rates based on the local AC power line frequency: 60 Hz for North America, and 50 Hz for Europe.
In the 1940s and 1950s, coupling of the ripple of a receiver’s power supply into circuitry – such as video amplifiers and high-voltage ...