Why do old TV’s always have that annoying high pitch noise when you turn them on?

Question

Why do old TV’s always have that annoying high pitch noise when you turn them on?

In: 3

Answer 1

In order to generate a picture, the electron beam inside the CRT has to sweep back and forth across the entire screen very fast–on a PAL TV it has to scan 625 lines every 1/25th of a second, which is over 15kHz. The high voltage components that sweep the beam make noise while doing that, which you hear as the high-pitched noise.