What is really fascinating about that, is the advert that says "Only 2 controls! Turn it on and select the channel."
I can't believe that I'd completely forgotten that you once had the horizontal and vertical controls on the CRT so you could re-position the picture in the middle of the screen! There was also a certain amount of frequency adjustment depending on the weather and your distance from the transmitter, not to mention the direction in which the aerial was pointed. With colour TV there was also a great deal adjustment required to the brightness, contrast and intensity. It was a very complicated business getting the picture correct, and only possible after waiting several minutes for the CRT to warm up. To watch a TV programme at a certain time you would need to start this process, and switch on the TV, a good 20 minutes before! Then sometimes they would overheat and just stop working until it cooled down again! They would break down frequently. TV repair men were never out of work. It made much more sense to rent rather than buy, because then you just got a new set when the old stopped working.