Do you remember in old TVs they had vertical tuning?

Question

and when the reception is bad the picture would start rotating! Why doesnt that happen in newer TVs ?

Answer 1

The newer TVs use a different system to get the picture to you.  In the newer TV, the picture is sent as a series of numbers, when the TV gets the numbers, it "paints" a picture.  This is similar to they way an image is produced on the screen of your computer.  Because of this, the image is either perfect or not there at all.

Answer 2

The picture is kept in place by signals at the end of each line and at the end of each frame (sync pulses).  Those pulses are detected and used to synchronize the picture scanning.  When the signal gets weak, those pulses cannot be reliably detected and the picture rolls up or down, or tears from side to side.  This will still happen with analog television, but the circuits have improved over the years so that the picture has to be almost unviewable before sync is lost.

Digital transmission will not have this problem.  If the signal gets too weak, the whole picture goes to pieces or disappears altogether

Answer 3

those days tvs are old style so its the best they got back then. back in the 50's tvs were so much of a technology back then, they would of cost 200-250 bucks just for the really old fashion black and white tvs cause of a new thing it was. it doesnt really happen in new tvs cause obvously the electronis inproved , be came more stable and durable, in which HD and better quality pictures and sound kicks in.