> A thought just occurred to me, as a result of a rather obscure train of thoughts, which ended in the known TV phrase: "Tune in next week..."
>
> In the old days, when the TVs came, I suppose you had a knob or something to tune them with.
>
> But I also assume there came a time when there suddenly was more than one channel around. (We had only one Norwegian channel for eons, I don't know how it was in the US -- and that's actually something I'd like to know, too.)
>
> Had the TV manufacturers foreseen this and installed a preset feature, or did you have to manually re-tune the TV to switch channels?
>
> Trav"before my time"holt.

Since I never saw a TV until I was almost 18, I think I'll field that question.
In June of 1951, I arrived at my aunt's house in Nashville and saw a strange blue flicker in her living room. It was coming from a large plywood box(about a meter cube) that was covered with contact paper and had a row of knobs across the bottom and up one side. There was a round 9 inch diameter screen and a speaker almost as big as the screen.
It showed a picture that, after I studied it for a while, appeared to be an old out-of-focus cowboy movie. There were knobs for focus, brightness, contrast, volume (with on-off), tuning and channel selection. The latter was the largest and it had a pointer that allowed you to select channels 2 through 13, but Nashville only had a channel 4. Little did I know that there were other knobs on the back that were nornally used by a qualified serviceman. Nashville had one more channel than it did qualified servicemen.
The old tv operated on vacuum tubes and generated so much heat you had to be careful what you placed on top of it. It would melt crayons or wilt flowers in minutes. It was a good place to dry socks, but it was too warm even for the cat. The picture flickered everytime the refrigerator came on. After a decade or two, Nashville got two more stations which gave it one for each network. The word was that some big cities would soon have so many stations, more channels would be needed. So the invented UHF and added another knob to the newer sets. You set the channel selector to "U," which was usually between channel 2 and channel 13, and then turned the UHF knob until another channel came up. UHF channels were usually weak and blurry, so if you didn't find one, it was ok.
About that time they started talking about color TV, but we knew that was impossible.
Did you know that TV sets now are about half the price they were in the 1950's? Maybe a little less.
How"Where have the rabbit ears gone?"ard