View Full Version : Some History of the Rectangular Color CRT
akent36 03-24-2014, 09:45 AM Lately I have become interested in the saga of Motorola and National Video developing the first practical rectangular screen color CRT during 1961 to 1963 and have been searching Chicago Tribune archives on line. National Video was publicly traded and their stock went from about 115 in October 1965 to zero when then they folded four years later. There is also another part of the story involving Admiral--both Motorola and Admiral decided to build color CRT plants in early 1965 and they were both ready to go around October 1965. Admiral's cost $18 million which they could hardly afford since their profit picture hadn't been that great since the mid 50's. Motorola must have built a smaller plant because they only spent $10 million. It is not clear to me, but it doesn't look like Admiral ever got past the pilot run stage into full production, and Motorola closed their plant after nine months of effort.
old_tv_nut 03-24-2014, 01:35 PM Admiral did get into production. At one point, Motorola made a deal to buy Admiral CRTs for some TVs. I remember the engineers at Motorola grumbling because they felt the Admiral tubes would fail in warranty and cost more in total than they were worth.
Electronic M 03-24-2014, 05:14 PM There was also the Westinghouse rectangular color sets of 1957...http://www.earlytelevision.org/westinghouse_h22t155.html
The ETF article says they had convergence issues, but IIRC the restoration write up on two of those sets that appeared here some years back showed they had pretty decent convergence.
David Roper 03-24-2014, 06:53 PM Only the one done by Steve K is known to have gotten a full restoration; the other set's current working status is unknown AFAIK. Good convergence is possible, but not stable due to an odd issue with the shadow mask changing shape.
dieseljeep 03-24-2014, 07:47 PM Admiral did get into production. At one point, Motorola made a deal to buy Admiral CRTs for some TVs. I remember the engineers at Motorola grumbling because they felt the Admiral tubes would fail in warranty and cost more in total than they were worth.
They were dogs, all right. Admiral was including a three year warrantee on the CRT's in their sets. I was disappointed to see EIA 101 CRT's in Motorola sets. They were the lower end models, plain cabinets and metal table models.
I still think, the biggest disappointment in CRT quality was the Zenith's of the late 80's to mid-90's. :scratch2:
Dude111 03-24-2014, 09:22 PM The CRT set is the BEST video equiptment ever made :)
Jon A. 03-24-2014, 09:30 PM There was also the Westinghouse rectangular color sets of 1957...http://www.earlytelevision.org/westinghouse_h22t155.html
The ETF article says they had convergence issues, but IIRC the restoration write up on two of those sets that appeared here some years back showed they had pretty decent convergence.
I always thought convergence issues were the reason for early color CRTs being round. I reckon even their designers thought them somewhat compromised, but there was nothing they could do at the time.
Sandy G 03-24-2014, 10:16 PM My Dad got a 17" Sears color set in 1964-65. It had a "Rectangular" CRT, predating the USA models by a good 6 months. Either we got a lemon, or the Japanese hadn't quite figured out "Quality" at that point in time, it was actually a Toshiba, IIRC. He wisely bought a service contract on it, on a couple occasions, the damthing took a dump before the service guy got out of our driveway good... My dad sold it, & bought one of the then-new Porta-Colors. The Sears soldiered on, never giving a spot of trouble to the guy my dad sold it to..
Jon A. 03-24-2014, 10:29 PM I've seen those Toshiba sets discussed here before.
old_tv_nut 03-24-2014, 10:33 PM I always thought convergence issues were the reason for early color CRTs being round. I reckon even their designers thought them somewhat compromised, but there was nothing they could do at the time.
Convergence was one factor, but there was also structural strength, thermal stress considerations for processing cycles, and so on.
Electronic M 03-24-2014, 10:43 PM I always thought convergence issues were the reason for early color CRTs being round. I reckon even their designers thought them somewhat compromised, but there was nothing they could do at the time.
I always thought the reason was because they developed them in the early-mid 50's when round CRTs were still being put in new sets, and metal cone tubes (which had some advantages for shadow mask based tube development) were mostly available in the round screen variants, and due to high set price, already investing too much in color development, and poor color TV sales they did not feel like sinking more money just to make a squarer tube.
marty59 03-25-2014, 08:17 AM Pincushion correction was the problem as deflection angles were being increased as well. Adding additional circuitry was required and had to be developed to deal with it. Even then, correction wasn't 100% either.
old_tv_nut 03-25-2014, 02:21 PM According to ETF Zenith developed a rectangular color CRT in 1954. Does anyone know if one survives? ...
There seems to be some doubt as to whether any were ever constructed, or if it was only a conceptual display for the distributor's convention.
Dude111 03-25-2014, 06:10 PM It saddens me the response of brainwashed people...
Example: One time a friend came in my room and saw my 3 CRT sets (2 computer monitors and my TV) and they looked @ my TV and said "Boy how do you see anything??"
Totally insane...... I just said "THIS IS NOT A MOVIE THEATHER,I havent ever minded a small screen"....... (My set is 13" i believe)
Its really very sad ppl have been so conditioned/re-programmed to think crap is better.....
ChrisW6ATV 03-25-2014, 06:13 PM Those Toshiba rectangular CRTs have been considered as possibly useable in CT-100s or other 15GP22 sets with some adaptation, if I remember right. (Something just to get a picture onto the screen rather than any kind of permanent replacement.)
bgadow 03-25-2014, 10:13 PM The MAARC newsletter (Radio Age) did a history of Admiral a few years back, from its inception up through the sale to Rockwell. I found the section regarding their crt manufacturing interesting. They apparently put the installation in an existing facility (the article mentioned they had to remove the roof.) Once up and running they had constant problems with quality control-problems nobody could straighten out. Later, when the equipment was being disassembled, it was found that somebody had sabotaged the water purification unit by tossing in some scraps of metal. This apparently kept them from ever being able to turn out a truly clean tube?
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