RCA had really developed for the first trinitorn?

[firenzeprima]

Originally Posted by andy

The Apple tube was the original Indextron.

very interesting, thanks

[Steve McVoy]

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)

[firenzeprima]

thank you very much!

[jhalphen]

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

[firenzeprima]

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

[cbenham]

Originally Posted by firenzeprima

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

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.

[firenzeprima]

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.