... It's funny Tv's have been around for what 70-80 years and for most of that time we all had SD tube Tv's with out much change then within the last what 5 years we have gone from SD to HD to 3D and now 3D without glasses.
There were quite a few changes in TV technology over the years. Aside from going from B&W to color (that is a dramatic change), they also went from round picture tubes to ones that more closely matched the actual broadcast format, with eventually flat fronts to the screens on high end models instead of rounded. They also went from being full of tubes and being terribly unreliable to being solid state (except for the picture tube). I remember having to turn on a TV about 10 minutes before wanting to watch it so that it would "warm up" and stabilize. During those first few minutes, it was pointless to adjust the set, as things were in a state of flux and constantly changing.
Also, people used to have to "fine tune" channels rather than just switching to them; the older people will know what this means. Vertical hold and horizontal hold controls were also necessary, which will probably be meaningless to the young whippersnappers reading this. Basically, in order to get a picture at all that you could watch, you would have to fiddle with several knobs. And after you got it right, you might have to get up again in the middle of your program to readjust them because you lost the picture. And, of course, you would have to get up, as there were no remote controls in the early days, and remotes were expensive in the 1970's (and didn't have those sorts of controls on the remotes anyway).
Thinking about this makes me really glad about all of the improvements in TVs that have taken place over the years. You really do not want a TV from the 1950's.
A couple of other changes: Early on, they got rid of channel 1, and later added UHF frequencies.
My brother went to electronics school in the 1970's, and for a project, he repaired a TV from the 1950's that was very high end (supposedly retailed for about $1000 in 1950's money!!!!), a color set that had a picture about the size of a modern 27" TV, but with severely rounded corners (it had a round picture tube), new enough to not have channel 1, but old enough not to have VHF. It was a huge thing, with two way speakers, one woofer and with two tweeters aimed at an angle to disperse the sound in the room (it was the best sounding TV I have ever heard). I don't know if it was because he never got it right, or was this way from the beginning, but B&W shows were more brown and white, giving a sepia tone to the picture, that I thought was very pleasant, particularly for westerns, as it made it look like old fashioned photographs. But of course it was not getting the B&W right.
Another change was adding stereo to TV broadcasts, which enabled people eventually to have Dolby Pro Logic from their broadcasts, instead of the original mono sound. So it is not just a change in picture that occurred before HD.
The more I think of it, the less significant a change HD seems to me. The difference between a modest TV just before HD and a 50 year old TV (even a high end model) is vast. If you were forced to live with one of each, you would instantly know that there was a night and day difference between two such TVs. Using an HDTV is very much like using a TV from just before HD. But you would be quite unprepared to deal with a 50 year old set if you practiced with a TV from just before HDTV and had no experience with what had come before.
