RCA had really developed for the first trinitron?
 

To read the reports the site http://www.earlytelevision.org/rca_d...al_onegun.html, it would seem yes. The project, it says, was abandoned because of convergence and low resolution problem.
Really interesting and still shows the absolute superiority of technology RCA

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you you you are right. GE developed the Cromatron from which developed the Sony Trinitron, but as I read, if I understood correctly, the basic idea had the RCA who then left for the reasons we know, was only to please a capacity of RCA in those years above all others.
Fernando

I thought CBS developed the Chromatron. Then I think it was their parent company {Paramount I think} that forced them to sell the design to Sony and they completed the development of it. I could be wrong though.

RCA developed a lot of stuff that they then never did anything with. Or much with. Liquid crystal displays was one thing that was developed at RCA labs, and then essentially abandoned (except probably patent licensing). And RCA developed CMOS and then they did develop some product (the CD4xxx series of logic chips, and the 1802 microprocessor) but it was other companies that took CMOS to where it is today.

In the late 70's RCA was kicking around the idea of CRTs with the electron gun down below, instead of the usual all the way behind the plane of the display screen. Like the Sony watchman CRTs except with the prospers on the front glass instead of Sony's prospers on the back glass. Would have made for a shallow TV cabinet. Heard that it did work, but RCA just finished building a new regular CRT manufacturing plant, and this new CRT would make that obsolete, so it was shjtcanned...

then I confirmed what I was saying, RCA over all. A true giant of the electronic world, as the Dutch Philips (NORELCO) was in Europe!

The Chromatron was developed by Ernest O. Lawrence (a physicist who worked on particle accelerators) and was often called the Lawrence tube.

http://www.earlytelevision.org/chromatron.html

thanks a lot! and cromatron in which color TV SET was used? and for how many years? or remained only a project in the drawer that after sony has finalised and marketed?

Search www.earlytelevision.org for more - it lists which companies developed sets using the Chromatron. Most or all of them never went beyond the prototype stage. One thing that was controversial about the tube was that it used about 30 or 40 watts of 3.58 MHz sine wave power to switch the color grids, which was a potential RF interference problem.

thanks for the information, I also thought that this type of kinescopio had not gone the other experimental study because I had never seen or heard of, TV SET that used the cromatron:thmbsp:

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if someone knows something about these things, please keep us informed, Thank you!

I thought the Philco Apple tube was the "original Trinitron". It's only a vague memory of something that someone explained to me, though.

Charles

Just because it has a striped screen doesn't make it an "original Trinitron."

The Trinitron still had 3 beams. The Chromatron and Apple tubes had only one electron beam, altough they used a striped screen. The Chromatron focussed the beam onto the desired color by means of charged wires behind the screen. The Apple was a beam-index tube that required the beam to be very narrow so it would hit only one color stripe at a time.

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very interesting, thanks

All of the single gun early color tubes, including the RCA 1950 prototype, suffered from very low brightness, since they depended on a single gun to illuminate three color phosphors.

As far as the 1954 Zenith rectangular color set,

http://www.earlytelevision.org/zenith_rectangular.html

there is no surviving sample. We have a CBS Hytron 22 inch rectangular tube on display,

http://www.earlytelevision.org/color_crts.html

and there is also a Westinghouse 22 inch tube that was supposedly not built by CBS, but looks very similar. Three Westinghouse and CBS sets with these tubes may be around, but we've never gotten photos of them.

http://www.earlytelevision.org/21_inch_color.html

Finally, there is a photo of a DuMont rectangular tube, from 1954, but no surviving example.

http://www.earlytelevision.org/dumont_color_crt.html

(bottom photo)

thank you very much!

Hello Gentlemen,

BTW, Welcome! FirenzePrima, nice to have another Euro-Vintage Color TV fan on board.

here's a picture of the Sony booth at the launch of their version of the Chromatron in 1961.

The venture was a failure and Sony quickly removed the set from the market. They then developped the Trinitron, in time for the 1968 Tokyo Olympic Games, which was the true launch of (NTSC) color in Japan

Here are a few pictures from one of my totally recapped Indextrons nicknamed "Son of Apple" :)

http://audiokarma.org/forums/showthread.php?t=120906

Hi Charles! in a nutshell, Chromatron/Lawrence Tube/Indextron = 1 gun switched at subcarrier frequency in sync with beam deflection to correct phosphor color.

All others, variants of 3 gun tubes. The Trinitron "confusion" comes from 1 gun - 3 Beams - 1 (big) focussing lens. Ahhh marketing!

Best Regards

jhalphen
Paris/France

everything is very interesting, I thank you for the additional information you've given. Fernando from Florence

Here's what I have on the chromatron from a familiar source:
[posted on AudioKarma by WVSAZ on 01-28-2003]

Re: DuMont
The tube that led to the Trinitron was the "Lawrence" tube, invented by Dr.
E. O. Lawrence, who also invented the Cyclotron. This was a concept on paper only, Dr. Lawrence never built the tube. DuMont obtained the rights to it and attempted to build it, discovering that the design was flawed. They had
named it the "Chromatron" and were working to correct the design flaws when
Paramount Pictures, who owned the controlling interest in DuMont, forced
them to sell it to Sony for the cash. Sony then completed the development
work, and introduced it as the Trinitron. Paramount's interest in DuMont was
financial only, they were not interested in the development of television.
They ultimately caused the collapse of DuMont.

i found others information it on www.sony.net

After the settlement of the strike and the successful launch of their ADR stock, Sony had returned to normal. An eventful 1961 drew to a close on December 16, when Sony concluded a contract with Paramount Pictures to provide technical assistance in the production of a chromatron tube and color television receiver utilizing it.

Sony was not alone. Dissatisfaction with the shadow mask screen was widespread. One possible substitute was the banana tube. Television signals were sent through this long thin tube, followed by RGB signals flashed at timed intervals, shuttered through a striped filter rotated through the beam. The rotating sound made a clattering noise, which in Japanese is onomatopoetically referred to as karakara. The color television using it was given the dubious, but amusing, name of karakara television, because of its phonetic closeness to the word color. The apple tube, which had been developed by Philco, was another possibility. Then there was the chromatron tube. This was the invention of famous American atomic physicist and Nobel laureate, Dr. E. O. Lawrence.