Radio-TV Experimenter December 1964 / January 1965 -
Seven-page article on the Lawrence Chromatron color tube.

http://www.bretl.com/tvarticles/rtve1264/rtve1264.pdf

Reminder: a large assortment of TV-related articles are posted at:
http://www.bretl.com/tvarticles/tvarticles.htm

Chromatron showed great promise but have never seen one.

Could be because research funding was sponsored by "Paramount Pictures"

Yeah, Paramount would really want this to succeed & empty more theater seats to TV.

Like when General Motors started "magnanimously" buying Electric Trolley routes
and guess what happened next.

I have read that Sony secured a license in 1962 and produced about 13,000 17 inch Chromatron sets, using vacuum tubes in 1964... It was a disaster! (would love to have one of those in my collection, however)
Later, much the same target/mask structure plus the inline gun structure from GE plus an innovative focus structure yielded the Trinitron, so I guess that the Chromatron design was not really a dead end.
jr

...

Says it nearly sent Sony broke!

"The production problems were never solved, and led to increasing tension between Ibuka and Morita. In November 1966 Kazuo Iwama told Susumu Yoshida that the company was close to ruin..."
http://en.wikipedia.org/wiki/Chromatron#Sony.27s_attempt

Hollywood had a hand in writing a later chapter in this saga as well. Sony received an Academy Award for the Trinitron some years later. It's kind of ironic, since Hollywood had lined its pockets with the hard-earned money of people in the radio/television industry for decades. It was both a slap in the face and a push down the road to oblivion for a proud and vital segment of our economy.

I found this Picture of Ibuka and his 1973 Emmy... did Sony get an Oscar as well?
jr

No, my mistake. it was an Emmy. Read the info at their website:

http://www.sony.net/SonyInfo/CorporateInfo/History/SonyHistory/2-14.html

Quite an honor nonetheless, for hard work and dedication to an ideal. It's a shame few know that RCA had also won the Emmy for the three-gun CRT (1956) and a videotape cartridge design (1974). Remember, it was Americans who prepared the media onslaught, along with government apathy, that delivered the one-two punch ending thousands of manufacturing jobs we still haven't replaced today.

Even fewer people know of this amazing (for its time) device:

http://www.rcaselectron.com/

A few words about the Chromatron can be found in the biography of E.O. Lawrence
entitled 'An American Genius'. Lawrence (1900-1958) was a talented applied
physicist, and he was involved with a number of other people in the development
of that picture tube. His early death, along with electromagnetic compatibility
problems, may have hampered the commercial succes of the Chromatron. Sorry
I don't remember the author's name, I believe the book was published in 1968.

Sony ..produced about 13,000 17 inch Chromatron sets, )


Some collectible this set would be!

Patent very complex, intricate. The work of a genius in 1951
http://www.google.com/patents?id=7n9fAAAAEBAJ

But almost impossible to implement..

But one aspect did work very well - the hype
http://www.bretl.com/tvarticles/rtve1264/rtve1264.pdf
This was a great journalism -
Must've got Sony excited !

Just another idea that the Japanese took and ran with Just like the early consumer video recorder developed by Ampex who went bK and sold the rights to JVC.

I used to work for a guy who was sent to Chromatic Labs in the 50's by his employer (Thomas Electronics) to learn to build the Chromatron tube. His comment to me was, "I was there two #$@%!%$ weeks and didn't see one $#@%$## good tube."

Saw this thread while Google searching the Chromatron.

Sony actually marketed a 61/2 inch color hybrid Chromatron for approximately 3 months starting July, 1968 and quickly replaced it with the first Trinitron in the US. In October, 1968.

The Chromatron was model KV 7010U and the Trintron was the model KV 7010UA.

The KV 7010U used a 3 gun inline system like the Trinitron, but instead of the Aperture grill, they used a fine wire color selection grid similar to the Original Chromatron with post acceleration, two high voltage power supplies with 3 connections to the CRT bell. Inside the set there is a label attached to the CRT, it recites "Sony Chromatron licensed under Patents of Paramount Pictures Corporation.

So the Chromatron did not die in Japan, it made it to our shores for a brief period in time with very low production numbers.

Chromatron showed great promise but have never seen one.

Could be because research funding was sponsored by "Paramount Pictures"

Yeah, Paramount would really want this to succeed & empty more theater seats to TV.

Like when General Motors started "magnanimously" buying Electric Trolley routes
and guess what happened next.

Not quite so . . . .

OK youngsters, lets review history a bit.

At the time the ABC Network was owned by Paramount Theaters and was in the process of switching to color and managed to get more shows on the air in Color than CBS did.

Officially Paramount Theaters and Paramount Pictures were separate, but unofficially both were intertwined.

Funding from Paramount brought ABC from a distant third place, to barking at CBS's heels in ratings, but not in number of stations.

Jas.

I have read that Sony secured a license in 1962 and produced about 13,000 17 inch Chromatron sets, using vacuum tubes in 1964... It was a disaster! (would love to have one of those in my collection, however)
Later, much the same target/mask structure plus the inline gun structure from GE plus an innovative focus structure yielded the Trinitron, so I guess that the Chromatron design was not really a dead end.
jr

Actually, the 17 inch Chromatron went into pilot production only. The 13,000 to 17,000 Chromatron's that were sold in Japan only, had a 19 inch CRT. They sold in 1965 and 1966. It was an upright consollete.

I have two Sony KV-7010UA's but have never seen the U version. I wouldn't be surprised if a few of them survive today, as they were ULTRA-expensive, and I bet people kept them in a closet when they quit working. Is there anyone here with a U?

Charles

I have two Sony KV-7010UA's but have never seen the U version. I wouldn't be surprised if a few of them survive today, as they were ULTRA-expensive, and I bet people kept them in a closet when they quit working. Is there anyone here with a U?

Charles

I have one. It is a hybrid Chromatron.

I just wish that guy would send MY 7010 back to me...

I have one. It is a hybrid Chromatron.

PLEASE_-get some pictures of the interior for all of us!!!

PLEASE_-get some pictures of the interior for all of us!!!

Okay, hope this works. If you go this link, a lot of photos inside the set. If you have a slow Internet connection, give it time to load. You will need to scroll down to 1968 about half way down the page, more then 20 photos.

http://www.visions4.net/journal/time-line/page-two/page-two-a/page-three/page-three-a/page-five/

If you go to this link, you can see screen shots. Same thing, you will need to scroll down to 1968.

http://www.visions4.net/journal/time-line/

The Trinitron was a game changer for sure, even the first models deliver a picture that's superior to most later sets and certainly much better than anything else made at the time.
By comparison GE was making the Porta Color set around the same time frame, probably one of the worst color pictures ever made, but they were cheap and Sony was always a premium priced set.

This is a image of the label attached to the Sony KV 7010U CRT.

http://i184.photobucket.com/albums/x117/etype2/image.jpg

The portion blocked out reads "Licensed under Patents of Paramount Pictures Corporation" I have another photo showing that and I will try to post additional photos directly to this site.

I would NOT really consider this chromatron a "hybrid set", since only the 2 HV rectifiers are tubes, Many sets in that time period , and even later, were labeled "solid state" but still had a rectifier tube. ALL o0ther ckty. looks to be SS.

I would NOT really consider this chromatron a "hybrid set", since only the 2 HV rectifiers are tubes, Many sets in that time period , and even later, were labeled "solid state" but still had a rectifier tube. ALL o0ther ckty. looks to be SS.

The reason I'm calling this a hybrid Chromatron is that we believe it has 3 inline beams within a single gun like the Trinitron, as the original Chromatron used a single beam. It has a fine wire selection grid visually confirmed instead of the aperture grill.

Treasonous sale of national assets to a foreign entity. Paramount spit upon all the American electronic factory workers who spent their money watching their films. Someone should have gone to jail. History is repeated with the sale of Zenith's LCD research to S. Korea. Will we ever learn?

Treasonous sale of national assets to a foreign entity. Paramount spit upon all the American electronic factory workers who spent their money watching their films. Someone should have gone to jail. History is repeated with the sale of Zenith's LCD research to S. Korea. Will we ever learn?

.... And GE wanted to license the inline Porta Color CRT to Sony and Sony said no thank you, instead buying the rights of the Chromatron from Paramount whose engineers said was hopeless. I give Sony credit for trying even though they failed with the Chromatron, because after all it led in the development of the Trinitron, the most successful color CRT in history. They had a 40 year run with it and big time profits.

Then there was RCA giving up on LCD, Ampex, Eastman Kodak and te beat go's on. Yes, will we ever learn?

I doubt we will ever return to the great business minds that made America such a powerhouse in years past. We have witnessed the failure of a system that was fine-tuned to make life good for the masses. What we have today is so pitifully obedient, if Wall Street can't make a haul off it, it doesn't get to survive. If it does, a mere pittance is handed to third-world workers who barely scrape by.

I've watched a vibrant industry I was part of (biomediccal electronics) for over 20 years simply evaporate into mostly offshore production. I now work elsewhere with brilliant minds from all over the globe on innovative products that hopefully will take their place on the world market, but the model is reworked so that very little of what we buy today is produced by our own hands. It was so much easier when we just worried about our own good and let the trade tariffs that served us so well since Colonial times do their job.

What I find so fascinating about the Sony KV 7010U Chromatron is why it was even released. My research shows it was only on the market for approximately 3 months starting July, 1968 and that may be optimistic because Sony started marketing the KV 7010UA Trinitron in October, 1968, I know because I saw one in the Sony showroom on Fifth Avenue in New York at that time.

The KV 7010U is part Chromatron and part Trinitron and Sony completed development on it by Spring, 1967. I speculate they pushed it out to the market under pressure of their shareholders to market the first Sony color TV and the Trinitron was not yet ready.

We have witnessed the failure of a system that was fine-tuned to make life good for the masses.

What we saw wasn't so much a "failure" as the carefully planned and orchestrated destruction of a system that was designed to make life good for the masses, so that the "1%" could reap even more profit.

US manufacturing didn't "die". It was KILLED, and those responsible went on to tank the entire world economy, with no repercussions whatsoever. "Too big to fail" really means "Too Rich to Jail".

Amen to that. Not likely to change in my lifetime...

The truth of the matter is American company's lacked the foresite to see the future. They only looked at short term profits, unwilling to invest in long term projects. If American companies would listen to their engineers we would be in a different place, instead they rule by committee. I have seen it happen time and time again in my 67 years on this planet.

Sorry that the Japanese Chromatron I brought up stirred up bad feelings.

The truth of the matter is American company's lacked the foresite to see the future.

Well not General Electric (doing much better than Sony today)..
GE wisely exited television just as Sony was ramping up..:scratch2:

Americans (knowing it won't work) sell Chromatron to Sony
Sony burn through billions then ditch it for a modified shadowmask nothing like a Chromatron.

Sony boss brags in book (http://www.amazon.com/Made-Japan-Akio-Morita-Signet/dp/0451151712/ref=cm_cr_pr_product_top)about Japanese superiority
just before Japan slides into a 25 year recession

One of the BIGGEST blunders in tv history, was RCA giving up the rights to the lcd. They could have produced a workable B/W pocket tv by the late '60's and a COLOR tv a few years later. They would have owned the tv business by now, , bigger than Sony ever was... lock, stock and barrel!! instead...they pi**ed it all away..and they are a "nobody " now.

That pix with that engineer holding that little B/W LCD monitor with a GOOD test pattern on its screen in 1966 or so just hurts me to see.....

http://www.visions4.net/journal/time-line/
It is amazing to see an actual Chromatron picture, and yes it shows unique qualities.
Trust the Japanese to bring it to actual production no matter what the loss.

Radio-TV Experimenter December 1964 / January 1965 -
Seven-page article on the Lawrence Chromatron color tube.

http://www.bretl.com/tvarticles/rtve1264/rtve1264.pdf

Reminder: a large assortment of TV-related articles are posted at:
http://www.bretl.com/tvarticles/tvarticles.htm

awesome links, thanks.

Here's a 1969 Popular Science article about LCD's and work to make LCD TV's: http://books.google.com/books?id=wSoDAAAAMBAJ&lpg=PA59&dq=liquid%20tv&pg=PA56#v=onepage&q=liquid%20tv&f=false

And a 1970 PS article on LED's: http://books.google.com/books?id=-AAAAAAAMBAJ&lpg=PA76&dq=light%20emitting%20diode&pg=PA76#v=onepage&q=light%20emitting%20diode&f=false

According to the 1969 article RCA could create a high resolution still image, but was totally unable to make a moving picture.

As I understand it, what finally made LCD tv a reality was the built in computers that can process the huge amount of information needed to create a moving image. Electronics of 40+ years ago were unable to process a signal and turn on and off all those tiny dots quickly enough.

Radio-TV Experimenter December 1964 / January 1965 -
Seven-page article on the Lawrence Chromatron color tube.

http://www.bretl.com/tvarticles/rtve1264/rtve1264.pdf

Reminder: a large assortment of TV-related articles are posted at:
http://www.bretl.com/tvarticles/tvarticles.htm

Are we defending RCA or are we discussing the Chromatron, the subject of this thread?

How many Sony Chromatrons estimated today?
How Much are they known to change hands for?

How many Sony Chromatrons estimated today?
How Much are they known to change hands for?

The Sony KV 7010U Chromatron was marketed July, 1968 and replaced by the Sony KV 7010UA Trinitron approximately, October, 1968. Based on that and 3 known serial numbers and chassis numbers of the the two versions, best guess speculation, possibly one thousand or less Sony KV 7010U Chromatron's were produced. I could be way off though, just best guess speculation as to what we know now.

Anybody's guess as to how many survived today and the value, it's whatever the collector is willing to pay. I can say for me personally, very rare and would pay appropriately.

Let me get this right: the Chromatron they sold in the US, 7010U,
was a three gun tube, inline guns, with ? (one or three) ? lenses
(Trinitron has one, PortaColor has three) and TWO HV voltages, one
to the screen and one to the wire grid resulting in a focusing effect
between grid and screen. There was no AC applied to the grid.

Is that correct reading? What about the (19 inch???) Chromatron
said to have been sold in Japan???

I'm mixed up.

Let me get this right: the Chromatron they sold in the US, 7010U,
was a three gun tube, inline guns, with ? (one or three) ? lenses
(Trinitron has one, PortaColor has three) and TWO HV voltages, one
to the screen and one to the wire grid resulting in a focusing effect
between grid and screen. There was no AC applied to the grid.

Is that correct reading? What about the (19 inch???) Chromatron
said to have been sold in Japan???

I'm mixed up.

Hope this helps.

1. Sony put into pilot production a 17 inch one gun Chromatron in Japan only, it was not mass produced.

Because of the many problems with the one gun 17 inch they decided to,

2. Introduce a 19 inch Chromatron, but it used three guns, which departed from the original design of a one gun. This is the set that was mass produced in Japan only in 1965 and 1966, 13 to 18 thousand units.

They still had problems, extremely difficult to manufacture, time consuming, technical problems, they pulled the plug on the Chromatron but they did not give up. This led to the development of the Trinitron. For Sony, it had one gun, three inline beams, one lens and the Aperture grill was similar to the Chromatron, meaning it had the vertical stripes and passed much more light like the Chromatron. They did not want to copy the American system. Essentially the Trinitron was born from the Chromatron.

Now the interesting part, before Sony marketed the 7 inch KV 7010UA TRINITRON, one gun, three inline beams, one lens, in the U.S.,

3. They actually marketed the 7 inch, KV 7010U CHROMATRON one gun, three beam, one lens CRT with a color selection system like the Chromatron. A hybrid Chromatron.

4. Approximately three months later in October 1968, the KV 7010U CHROMATRON was replaced by the KV 7010UA TRINITRON.

Why did Sony introduce the KV 7010U Chromatron only to be replaced so soon by the KV 7010UA Trinitron?

Only speculation on my part, it was known that Sony had a few production mules of the 7 inch Chromatron, the development was finished by Spring, 1967. Sony showed the 7 inch prototype at a press conference in Summer, 1967 in New York and said it would be introduced the following year. I believe that share holder pressure, dealer pressure to get Sony's first color television on the market, (they were behind their competitors) caused them to release the KV 7010U Chromatron because the Trinitron was not yet ready. Possibly they wanted bragging rights as well to say they actually marked a Chromatron in the States. All the while they were working hard to get the Trintron to market. Sony's chief CEO pushed the engineers 24/7 to meet the production deadline.


Adding this: I don't have the expertise to tell you how the Sony KV 7010U Chromatron works. I do know that it has two HV supplies, three connections to the CRT bell, electronic purity adjustment and a color selection grid consisting of fine wires which focus the three beams. Perhaps others here can explain it further.

Hope this helps.


Adding this: I don't have the expertise to tell you how the Sony KV 7010U Chromatron works. I do know that it has two HV supplies, three connections to the CRT bell, electronic purity adjustment and a color selection grid consisting of fine wires which focus the three beams. Perhaps others here can explain it further.

What you wrote is what I more or less thought. It now boils down to
one question: is there RF on two of the three HV leads? If
so, it TRULY IS a chromatron, not just a larval Trinitron. If there
is no RF on any of the three leads, I would call it a larval Trinitron.

This question could be answered by a schematic or a scope with
its probe merely held a half inch or so from the CRT HV wires.

I believe the owner has a schematic ... it would be wonderful if
he could scan and post it! (the 7010U, not the 7010UA).

Doug McDonald

What you wrote is what I more or less thought. It now boils down to
one question: is there RF on two of the three HV leads? If
so, it TRULY IS a chromatron, not just a larval Trinitron. If there
is no RF on any of the three leads, I would call it a larval Trinitron.

This question could be answered by a schematic or a scope with
its probe merely held a half inch or so from the CRT HV wires.

I believe the owner has a schematic ... it would be wonderful if
he could scan and post it! (the 7010U, not the 7010UA).

Doug McDonald

I am the owner and unfortunately the service manual or schematic could not be found for the KV 7010U. I have searched extensively for them.

The service technician who worked on it said this:

“I suspect they are applying a DC voltage to the wire mesh and only using
it to focus the electron beams onto the correct phosphor stripes."

"The purity control on your set is probably varying the bias on the wire mesh.”

There is a label attached to the CRT bell identifying it as "Sony Chromatron Licensed under Patents of Paramount Picture Corporation"

The CRT tested very weak on all three beams (.1) and yet the KV 7010U still produces a very bright image due to the absence of a shadow mask or Aperture grill. I have screen shots. The promise of the Chromatron was to overcome the dim brightness of early RCA color, and no need to adjust for convergence, only one beam. The Sony KV 7010U shows very bright images, surprisenly bright for such low emissions.


Adding this: We compared the KV 7010U to the KV 7010UA. The KV 7010U has two HV instead of one, three connections of HV to the CRT instead of two, an electronic purity control instead of the standard control, the fine wire selection grill instead of the Aperature grill and the CRT bell is shaped diferently. Most of the circuit boards look the same.

What you wrote is what I more or less thought. It now boils down to
one question: is there RF

This question could be answered by a schematic or a scope with
its probe merely held a half inch or so from the CRT HV wires.

Doug McDonald

I went back to revisit a long list of emails exchanges with the service technician that repaired my KV 7010U. He said thinking about it later, he should have measured for RF radiation, but did not. He said DC voltage is applied to the color selection grid and creates an "electronic lens" which focus's the electron beams to the correct color stripe without need for convergence. That is why there is two HV supplies. It's called "post acceleration and focus effect"

I don't much about repairing sets and would not want to touch anything for fear of screwing things up.

I think that clears it up: its a Frankentron!
Neither Chromatron nor Trinitron.

Still, I want one!

I guess that the attraction from the selection grid against the screen anode voltage caused the aluminum "sputtering" issue in these--and it was NEVER cleared up--which ended the chromatron.

I guess that the attraction from the selection grid against the screen anode voltage caused the aluminum "sputtering" issue in these--and it was NEVER cleared up--which ended the chromatron.

I believe your right. When I first got it, I had an all blue screen. A few days later I turned it on, still an all blue screen, but an odd small bright spot appeared in the lower corner. After the service work was done, good picture and the bright spot was still there. I had it on for maybe 50 hours after service and it is stable, nothing else happened, crossing my fingers. I think the bright spot is from the aluminum flaking off onto the selection grid.

Anybody ever see a service manual for the Sony KV 7010U? I have one for the KV 7010UA.

Update: July 28, 2022
Nine years later, we now have the service manual for the Sony KV 7010U Chromatron and I got brave enough to open the cabinet and tweaked the drives, cleaned the tuner and replaced an antenna wire which looked deteriorated. I found a new Digital Stream digital converter box which has RCA A/V outputs. I set the box and channel selector to channel 4 and used an OTA signal from Phoenix PBS channel 8.5. All three inline cathodes within the single gun measure extremely low emissions, especially the red. The last two photos give an expression of the bad red, but we were still able to get reasonably bright images, a testament to the lack of a shadow mask or aperture grill. The colors are not accurate, but watchable. I don’t believe I posted screenshots prior, so see 4+2 static images below. Photos shot with an iPhone X, processed with Affinity Photo editor.

https://visions4netjournal.com/wp-content/uploads/2022/07/884F3D24-B229-4616-88F6-266A524877E6.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/07/421BE198-7FEE-4984-A63C-5030F43C9EBB.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/07/311C0C03-3121-4CB2-898B-2900A32F9130.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/07/A5D27756-3573-415E-89C6-6081AD2E954D.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/07/BB4CB3C8-E45D-42D8-98BD-A5DFA51E1C4E.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/07/7C15AC12-7A33-43D4-8AF2-2CDE2E2C3401.jpeg

Marshall, that last image I assume was when it was turned off. Even though it tests weak, the picture is very watchable. Sony really was an innovator back then. Thanks for posting those.

Marshall, that last image I assume was when it was turned off. Even though it tests weak, the picture is very watchable. Sony really was an innovator back then. Thanks for posting those.

Hi John,

Yes. The lens flares are exaggerated by the camera. Normally, the residual light looks like the second last photo. The red is almost non- existent, but if there is a strong red signal, this Chromatron displays it. I agree with you about Sony, now the Koreans took over television development. Sony seems to focus more on photography these days. They innovated mirrorless cameras. Just read this week that Nikon and Cannon are abandoning DSLR’s for mirrorless only. Thanks.

Thanks for firing it up and posting the shots.

Do I understand correctly that it has a grille voltage adjustment for purity? Is that accessible to the user? If so, could you get some shots of its effect?

I think this is true. There is a hole directly under the power socket on the Chromatron in the same location as on the Trintron which I read on the Trinitron adjusts the convergence. I have not adjusted either. Purity is not to be confused with convergence, correct?

I’ve located the background and drive adjustments, but not sure where the purity control is located. Have to check the schematic.

Purity is not to be confused with convergence, correct?


Correct.
Purity is each electron stream hitting only the correct color phosphor.
Convergence is all three streams hitting the same area on the screen (no color fringes on a white object).

I think that clears it up: its a Frankentron!
Neither Chromatron nor Trinitron.

Still, I want one!

The original Lawrence Chromatron experimented with both single and tri-gun electron guns. The one gun version got all the attention for obvious reasons. The Sony Chromatron KV 7010U is a true Chromatron. It has a single gun with three inline electron beams, post deflection focus thru a HV charged wire grid, also vertical unbroken RGB phosphors. Last week we improved the performance and I will post a video.

Sony Chromatron KV 7010U video.

https://videopress.com/v/n8ux4nBu

When viewing the video segments, keep in mind that all three cathode emissions are extremely low, especially the red. Video consists of a brief history, screenshots and three video clips.

Lots of moire and my camera lost focus numerous times. Haven’t had this problem with other sets. I wonder if it has something to do with post deflection focusing by the CRT?

Sony Chromatron KV 7010U video.

https://videopress.com/v/n8ux4nBu

Lots of moire and my camera lost focus numerous times. Haven’t had this problem with other sets. I wonder if it has something to do with post deflection focusing by the CRT?

I think it's more likely your camera trying to re-find focus as the moire' moved around. A contrast-based autofocus could be very confused by the contrast of the detail changing so critically.

I tried all the various focus settings and settled on “Single-shot AF” and “Expand Flexable Spot.” Found FL under 25mm made the moire less objectionable.

I forgot to try different shutter speeds under 30fps. The videos were at 1/25fps.

Edit: Just happy the thing works. :-)

We found new information about the Chromatron. Here is a summery of General Electric’s work. We tried to send this to the ETF, for some reason it won’t go through.

Filling in the gaps of Chromatron history, we recently researched General Electric’s work in developing their version of the Chromaton. It was called simply “PA” or Post Acceleration CRT.

Work started in 1954 and by late 1956, GE developed a three gun inline post deflection tube with a wire grid and vertical phosphor stripes. The wire grid was charged with 7KV and the screen was at 25KV. The design was easy to deflect and converge, but GE encountered difficulty in aligning the grid wires with the phosphor stripes. Additionally, the back scattering of secondary electrons created haze. The haze problem was later ameliorated. Unfortunately this tube never went into production. Thank you John Atwood for releasing the documents of Avon C. Campbell, a life long engineer at General Electric. Later in 1966, the world’s first 3 gun, in-line cathode ray tube went into production as the GE “Porta Color”. See the Porta Color here.

As a side note: Westinghouse worked on this approach with a prototype 20 inch PA CRT. We also learned that RCA tested the GE one gun PA and said to have “reservations”. RCA avoided at great cost, paying royalties to its competitors (think about the Philo Farnsworth litigation). RCA and GE were closely intertwined by cross licenses. Being cynical, perhaps the above described RCA one gun color tube was a GE design?

We have extracted the relevant discussions by the General Electric engineering department pertaining to the PA color CRT.

https://visions4netjournal.com/wp-content/uploads/2022/09/FED4B5CF-86AC-4C9A-9DB6-783D46DAFCC2.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/09/18E156DD-06AB-42DB-8AB3-0192BE167B61.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/09/0FEC3EE2-B2B2-42FE-AD40-75607179FB55.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/09/7F3B64A7-5EEA-4C9B-814C-28CDD82FBEE6.jpeg



Evaluation by General Electric of their own development CRT above.

Summery and recommendations above.

Internal General Electric engineering department photos.

https://visions4netjournal.com/wp-content/uploads/2022/09/19840915-68D1-4882-922E-C2986B6F6471.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/09/869A1127-98A7-4985-A5F4-6972919FD454.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/09/73D13CF2-47BD-4A1D-8BCB-BDD874B965C0.jpeg

https://visions4netjournal.com/wp-content/uploads/2022/09/87B8536B-5ED0-4067-BB46-00FF59BF60CA.jpeg


General Electric focused on five competitive systems and in the end, decided to contribute development to the Apple Super-Index system as the most viable cost effective technology to compete with RCA’s tri-color shadow mask CRT.

This information is in the public domain.



I see the photos won’t copy see my site. 10 photos partial post here. Please credit Mr.Campbell, Mr. Atwood and myself if these photos are posted elsewhere. https://visions4netjournal.com/422-2/.

UPDATE: Just now, we were able to send this to the ETF. I guess the email system did not like the photo links.

Thank you for finding and sharing this information, etype2. It is quite interesting.

It's great that this has been preserved.