How did the first televisions work?

=Television camera was at first a spinning mechanical wheel with a spiral of holes in it. An image would illuminate a photocell or not and send that signal to another such wheel with a lamp behind it replicating the photocells input and shining on a screen. When it was discovered that electron beams could be controlled and that they would light up a phosphorescent screen (radar and) T.V. was on the way. A Felix the Cat doll was the first T.V. image broadcast. It was used to set up the system.=