G'day all.

Been browsing the http://www.tvhistory.tv site and I came across an interesting colour television set which looks like a rectangular CRT was used. The set in question is the 1956 Emerson C-502:
http://www.tvhistory.tv/1956-Emerson-Brochure1.jpg

I went to the ETF site to find more info on it and according to this pic http://www.earlytelevision.org/1957_emerson.html the tube in the chassis appears to be a standard round tube while the assembled TV beside looks rectangular.

So I was wondering, why does the tube appear to be rectangular shaped in the completely assembled TV when the tube is round on the chassis? Or was the tube for the C-502 actually rectangular?

Am very curious about this TV set.

The tube in the chassis from the ETF link is obviously round, so maybe the art department was tasked with putting together a picture of a set which had not yet been built and took some liberties. It is possible (though I think unlikely) that Emerson initially intended to use a rectangular mask. I recall a Hoffman set with a 19AP4 which had a rectangular mask. That would seem about equally unlikely, but it happened.

looks like a real bad drawing of all the sets in the brochure

They could have really intended to put a rectangular mask on the TV, as in the pictures, even if they knew all along that the CRT would be round. The standard mask shape of all the other round-CRT color sets, commonly called "double-D", was seldom used on black-and-white TVs until about 1949, after which it became universal until rectangular CRTs were available. The double-D shape allows for a larger picture size with the same round CRT than other mask shapes, at the cost of losing picture information in the corners. I have never researched this, but I bet most TV programming in the roundie era was formatted to fit the double-D shape (the on-screen credits, etc.).