One additional obstacle for modern audiences is that the TV sets themselves are computers running software. They take a MPEG-2 or MPEG-4 file coming in some network port and send it to some mixed parallel/serial interface to a LCD or similar panel.
If you understood how a 1970s TV worked (specially the simpler black and white ones used in the first video-games) then imagining a circuit that would generate the needed signals was a bit easier.
If you understood how a 1970s TV worked (specially the simpler black and white ones used in the first video-games) then imagining a circuit that would generate the needed signals was a bit easier.