First rectangular set / CRT
 

Looking through photos of old sets, I've been noticing that round and "double D" masks seemed to fall out of favor around '51 or '52 or so and the more typical rectangular mask of the later 50s started to be the norm. I started to wonder as I looked through old pictures, do these sets have a round tube behind the mask, or are they rectangular CRTs? I have a Hoffman (beyond repair) that looks like your typical rectangular set from the front, but inside has a large 19" round CRT... a good percentage of which is covered up from view. When did rectangular tubes start to show up in '50s TV sets? Did they phase out round CRTs (in consoles and larger sets) rather quickly?

I have several sets from 1950 that have rectangular crts that would be my guess on when those crts came about.. Timothy

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I have some Admiral sets from 1951 with the 16KP4 CRT. The 16KP4/16RP4/16TP4 was one of the first (if not the first) rectangular CRT.

Some of the transition had to be marketing. Sell the modern look rectangular set, but burn up the old stock of round tubes. Just hide it under the trim until they go away.

The 621 was one of the exceptions. Rectangular mask over a round tube. I suspect the next RCA sets (630, et al.) had the round edges to give the illusion and reality of a bigger picture for the buck.

According to Peter Keller's book "The Cathode-Ray Tube", The Hytron 16RP4 was the first registered (Nov 1949) followed by the 16KP4 and 16RP4, in that order.
jr

Of course the prewar Telefunken E1 used a rectangular CRT. Probably the first rectangular CRT in commercial production.

A good site with pics and data is this one:
http://bs.cyty.com/menschen/e-etzold...efunken/e1.htm

I think I've seen a 1950 Emerson with a 14" glass rectangular tube, and definitely by 1951 there were plenty of 14, 16, and even 20" rectangular tubes, and they were in fact very rectangular. By 1952, there were 24" and 27" (metal) rectangular tubes. Cheaper models kept using round metal tubes for a few years, I guess to clear inventory of obsolete tubes. Many of those had rectangular masks, so as to "look" more modern.

Charles

I have a 1950 GE console TV(with AM/FM Radio and phono) that has a rectangular CRT. According to an ad that I found, it cost $500 new!

As I have worked on the set, I can verify that the CRT is rectangular, not a round tube behind a square opening.