How good was broadcast NTSC/PAL in practice?

[old_tv_nut]

Regarding noise, there were two main sources:

1) RF noise - just depended on how strong the signal was
2) Camera noise - just acceptable with image orthicon cameras at first, improved a bit with installation of solid state preamps; Plumbicon cameras had greatly reduced noise levels compared to image orthicons. There was also a difference in the character of the noise. Image orthicon noise had a flat spectrum, consisting mainly of shot noise. Plumbicon noise had a triangular spectrum rising toward higher frequencies. This made it less visible for a given total r.m.s. value.