Published March 24, 2014, amended July 8, 2015, all rights reserved.
I have been interested in alternative color television picture tube technologies developed over the past decades in an attempt to improve on the Federal Communication Commission RCA color system adopted 1953 in the United States. We don’t think the full story of the Chromatron has been told. We spent several years researching the Chromatron and originally the text and images appeared on several different pages of this Timeline website. Now I decided to merge this information and give the Chromatron it’s own dedicated page. It is not my intention to describe detailed technical data which would require volumes of material to post. Rather, a brief overview follows.
In 1951, Nobel Prize winner Dr. Ernest O. Lawrence, inventor of the Cyclotron from the University of California Berkley, invented the Lawrence Tube in his garage at home. The Lawrence Tube was unique in that it created the color image with one gun and one electron beam. It used no shadow mask, but instead, a grid of fine wires that’s were placed directly behind the vertically aligned tri-color phosphor stripes on the screen. The wires were charged with high voltage and when the single electron beam passed through the wires, in a type of electronic lens, they were accelerated and deflected onto the phosphor stripes. The original Lawrence Tube was conceived to work with both one and three guns. The one gun version received the most attention because of it’s simplicity and potential lower manufacturing costs. A three gun Lawrence Tube was brighter then the one gun. Both types were developed in prototype form. Dr. Lawrence later partnered with Paramount Pictures Corporation to develop the Lawrence Tube. View the Patent.
In 1951, Chromatic Television Laboratory, a subsidiary of Paramount based in New York City, with an office in Oakland California, was created to commercially develop the Lawrence Tube and renamed it the “Chromatron”. The work was done in tight quarters in the Paramount building in the heart of New York City on Broadway.
First details about the Lawrence/Chromatron appear in this article from Electronics Magazine, December, 1951. View PDF. Courtesy Electronics Magazine.
Here is an article from Billboard Magazine, published October 6, 1951, announcing the first Paramount sets incorporating the Chromatron CRT. This same article also announced that the first CBS-Columbia color sets hit the market on September 28, 1951.
This was a time when Columbia Broadcasting System (CBS) was working on the mechanical spinning color wheel field sequential color system (see a modern day field sequential color television on PAGE 4A) while Radio Corporation of America (RCA) was working on the electronic compatible Tri Color dot sequential shadow mask system (required reading, “The 1953 RCA Red Book FCC Petition”) and Color Television Incorporated proposed the line sequential system. During the FCC trials and public demonstrations of these color systems, Chromatic Television Laboratory was invited to demonstrate their Chromatron one gun color tube.
From left to right, one gun color CRT, black and white CRT and RCA three gun tri-color CRT. The Chromatron would work with CBS’s system, thereby eliminating the mechanical spinning wheel or drum and it would work with a one or three gun RCA system.
The CBS system was approved first by the FCC on October 10, 1950. In public viewing tests, it was deemed to have the best color reproduction, particularly the flesh tones. These first television sets were sold to receive the very limited color programming available. Then the war effort in Korea caused the suspension of production of CBS television sets. But, in the meantime, RCA greatly improved their color system and their biggest advantage was that black and white telecasts could be viewed on the Compatible RCA color system sets. The CBS system required an adaptor to watch black and white telecasts which dominated television programming at that time. See this article to get insights on the “color war” between CBS and RCA.
The first color telecast was a program called “Premiere” on June 25, 1951.
“Premiere” aired from 4:35 to 5:34 p.m. but only reached five cities: New York, Boston, Philadelphia, Baltimore and Washington, D.C. It has been reported that there were only 30 color sets in operation to view this first telecast.
Here, courtesy of Life/Google.com are a few select television screen shots taken from the CBS-Columbia 12CC2 color field sequential receiver during the first week of color telecasting in the United States as published in Life Magazine on July 23, 1951.
By March 30, 1953, the Chairman, Dr. Baker of the National Television System Committee (NTSC), considered the RCA and Chromatic tri-color tubes the most promising, but held out belief that a third tube might surface combining the best of these two tubes. RCA resubmitted their application of the compatible dot sequential electronic system to the FCC and they reversed their 1950 decision, approving the RCA system on December 17, 1953. (see the excellent 37 page brochure with beautiful photography prepared by RCA Department of Information, published December, 1953, courtesy KRIS TREXLER)
RCA manufactured and sold their first color television in April, 1954, the CT-100 with a 15 inch color tube, (12.5 inch viewable) using the phosphor dot/shadow mask tube. Sales were dismal, lack of color programming, the viewing screen was too small, (12 1/2 inches) and the set was too expensive. It was estimated that RCA manufactured 5000 CT-100’s, many of which were unsold. On August 8, 1954, RCA dropped the price of the CT 100 to $495.00 and rebated $505.00 to all who purchased the set. The industry was gearing up for the upcoming Motorola 19 inch color set and RCA’s new 21 inch set.
RCA licensed their 15 inch color tube to other manufactures such as Admiral and Westinghouse shown below, in an effort to promote the fledgling color television industry. A race to introduce the first compatible, electronic color television ensued.
This is the first color set, the Admiral C1617A which was introduced to the public on December 30, 1953.
A New York Times article published December 31, 1953.
On page 106 of the book, Television: The Life Story of a Technology, it is stated: “Admiral Television Corporation put the first receivers (color) on the market for $1175.00 on December 30, 1953, so that it could take a deductible tax loss on its color factory investment.”
Here is an article from the Pittsburg Post-Gazette published February 24, 1954.
An article from Billboard Magazine published May 29, 1954. The President of Admiral Corporation announced a price drop of their color television from $1175.00 to $1000.00. This indicates the Admiral color set was still being marketed as of the date of publication of the article, May 29, 1954.
In an article appearing in the Chicago Tribube published June 13, 1954, the President of Admiral Corporation declared the 12 inch color tube dead. This should give us insights as to the thinking and intent of further marketing of the Admiral C1617A.
Here is a specification sheet and an advertisement by a serviceing company for the Admiral C1617A courtesy of John Folsom and the Early Television Foundation.
Authors Note: We were a bit side tracked from the Chromatron chronology and gave the Admiral C1617A special attention and coverage because there is consensus by the collector community that this set was not the first color television marketed for sale. We have evidence the set was offered for sale or at least was shown to the public in an appliance/electronic store in the Pittsburg area as shown above and evidence of a price drop five months later, strong indicators that this set was offered for sale, but probably in small numbers. During this time period, if the general buying public could buy one, then the admiral C1617A was indeed the first color television for sale. It does not matter if the production numbers were low.
It was reported that the CBS-Columbia 12CC2 produced approximately 200 units and only sold 100 of them. The Westinghouse H840CK15 reportedly only sold 30 units in the first few months of sale and an unknown amount later. Do we erase their marks in history?
The second color set to go on sale was this Westinghouse H840CK15 on February 28, 1954 in the New York area. There are conflicting sources saying the set went on sale in March, 1954. This particular set was found in Phoenix and offered for sale in 2013. Photo by this author.
One of the constant complaints of the RCA system used in these first color sets, was the very dim color. One had to turn the lights down and draw the drapes in their homes to see the image clearly. Another problem, color fringing on black and white programs and blurred images with color. This is why the Chromatron (and other systems such as the Apple tube by Philco) were proposed. The RCA system used a metal sheet with many perforations or holes as a color selection method. This was called the shadow mask. The early RCA television tubes with shadow mask blocked 85% of the light from the three electron beams causing a dim image. The original Lawrence Tube only absorbed 14% of the single electron beam light energy, or 86% efficient.
Citation: THE PDF CHROMATRON-A SINGLE OR MULTI-GUN TRI-COLOR CATHODE-RAY TUBE by Robert Dressler from the PROCEEDINGS OF THE I.R.E. VOL.41, NO. 7, JULY, 1953.
In other words, the wire grid was much more transparent and this tube was as bright as a conventional black and white television of the time. Another big advantage of the Chromatron tube was in theory, it had perfect registration with no convergence requirements because it used just one gun. The Chromatron was said to be less expensive to manufacture, used fewer parts, smaller and lighter.
On June 2, 1953, the first color television telecast in England was conducted using an experimental field sequential system developed by Pye and Chromatic Television laboratory. Televisions with Chromatron tubes were set up in a children’s hospital to view the coronation of Queen Elizabeth II. The New York Times reported that a Chromatic representative concluded the test was a complete success. Newspaper clip courtesy of the Tipton Tribune, Indiana, June 2, 1953
Here is a 1953 specification sheet from Chromatic Television laboratory.
Update September 2, 2014: Here is a Chromatron Trade PDF by Chromatic Televisions Laboratory Inc., courtesy of the Smithsonian Museum of American History. On page 10, this author learned for the first time that Chromatic was developing beam index CRT’s as well. We annotated the text where this information appears. The PDF file is reversed starting with page 27. Just scroll down to page 1. View PDF.
One of Paramount’s interest in the Chromatron was for use with a pay TV system in hotels. In June, 1954, a test was done at the Park Sheraton hotel in New York City and 1600 guest rooms were hooked up using the Chromatron with the Telemeter coin set top box.
In a July 10, 1954 Billboard magazine article, it was reported that Chromatic Television Laboratory expected to release a 21 inch, one-gun Chromatron in early 1955 under the Chromatic label. Crosley was licensed to manufacture the set domestically and Philips of Holland had the international license.
Chromatic handled the basic development of the Chromatron and then about August, 1957, split the project in two sections, Du Mont in New Jersey was licensed for commercial picture tube fabrication and Lytton Industries in Emeryville, California for the military.
The original Lawrence Tube had 800 vertical phosphor stripes, 400 of which were green. The red and blue stripes were twice as wide as the green to equalize the color across the screen. Chromatic was working to increase the resolution by adding more vertical phosphor stripes. At first, 1000 stripes, later, a development CRT increased to 1600 stripes. Notice the design change in the photo above, the mass has been reduced and the tube takes on a modern appearance.
At about 1960, Chromatic was renamed Autometric Corporation (source Sy Yusem) and moved to an industrial-type building on the West side of New York city where one floor was devoted to picture tube development and another floor was for the electronics. Up to this point, neither Paramount, Chromatic/Autometric, Crosley, Philips, Du Mont, Lytton, Muntz, General Electronics and others had successfully developed a Chromatron receiver for the home consumer market.
RECOLLECTIONS OF TWO CHROMATRON ENGINEERS
Now I digress from the story temporally to tell you about Julius Shapiro, who I discovered after reading this story “THE WONDROUS LIVES OF JULIUS SHAPIRO” by Laurie Gwen Shapiro an Emmy-nominated documentary filmmaker as well as a novelist. She is currently working on her first non-fiction book, about a Lower East Side teen stowaway on Commander Byrd’s 1928 expedition to Antarctica. (Simon & Schuster)
Utterly fascinated, I looked up Laurie’s phone number and called her. She answered on the first try. I was hoping to find more information about her fathers involvement with the Chromatron project. A stranger was calling and yet she accepted me enthusiastically and all my questions. I learned that her father was interviewed to work on the Manhattan Project, he was a chemist, electrical engineer and computer systems manager.
He worked with Nobel prize winners and loves to play chess. He’s 93 now and doesn’t like to talk much about the past. He remembers his work at Chromatic as a project engineer working with the tubes.
Laurie invited me to call her father and so I did. It was a very pleasant conversation and Mr. Shapiro asked me to call his good friend Seymour Yusem and co-project engineer at Chromatic. “Sy would know everything I wanted to know” and so I did. Thank you sir.
I called Mr. Yusem, and left a voice message on his machine. He returned my call several hours later. It was a most interesting conversation and learned that Sy is 88 years old and started work with Chromatic from 1957 to 1962. He was a project engineer working on the Chromatron color tube receiver. He co-authored a technical paper with Robert Dressler entitled “THE PDF CHROMATRON-A SINGLE OR MULTI-GUN TRI-COLOR CATHODE-RAY TUBE” it can be found in the Proceedings of the I.R.E. Vol. 41, No. 7, July, 1953. Robert Dressler “was the brains of the project” and headed up Sy’s unit and has since passed away. Mr. Yusem sent me a copy and two other technical papers, thank you very much sir. (Laurie told me that Sy went to Japan to meet Sony, but he did not mention this in a follow-up email).
Mr. Yusem told me that the problem with the Chromatron was its resolution. It had very high brightness, but low resolution (not enough phosphor stripes across the screen) He said the RCA system had high resolution, but low brightness. He said RCA could have increased the brightness by enlarging the holes in the shadow mask at the expense of lowering the resolution.
Mr. Yusem explained the Telmeter pay TV system Paramount was working on in conjunction with a coin operated set top box. By inference, I make an assumption that the Chromatron was a part of this system because of earlier research on the subject.
Laurie’s father said Sony purchased the license and development rights to the Chromatron for one million dollars at a restaurant and Mr. Yusem said “When I was told that Sony had purchased the patents and development rights it was also stated that Sony had plans to transistorize the chassis. I took that to mean there was no future for me with Sony”.
Mr. Shapiro left Autometric a year earlier then Mr. Yusem and accepted a position as a Computer Systems Manager with another company.
Mr. Yusem left Autometric formerly Chromatic in 1962 and joined the CBS Television Network as a project engineer. He said they had a color TV plant. He received his BSE from City College.
Finally, Mr. Yusem sent me a black and white glossy 8×10 photo, an original of a prototype chassis built by Autometric in 1962 to demonstrate the Chromatron to various manufactures. The arrow points to the encoding section which could be changed for different encodings required for 1 gun or 3 gun Chromatrons. Mr. Yusem said Sony transistorized the chassis, which he felt was an achievement for that time. Thank you very much for this piece of history sir.
I feel honored to have spoken to these pioneering electrical engineers from the early days of development work on the Chromatron and to share their stories. We barely scratched the surface and would like to learn more. We will update you further.
Thank you Laurie for making it happen.
Update August 11, 2014: We took a pleasure trip to NYC with the intention of interviewing Mr. Shapiro and Mr. Yusem, but unfortunately unforeseen circumstances prevented our meeting.
Below, see the 1962 Chromatron prototype chassis.
Going back to the story, in March, 1961, Sony saw the Chromatron demonstrated at the Autometric booth within the IRE trade show in New York. It was used by the military to help identify friend or foe. What Sony immediately knew was this very bright tube is what they were searching for as an alternative to the RCA shadow mask color system. Akio Morita, Sony’s co-founder, attended the show with his young engineers and immediately called the President of Autometric to arrange a meeting. The next day it was done as Julius Shapiro said, “the deal was cooked up after an executive has one drink with a Sony man for a million dollars”. Sony had just purchased the patent and development rights to market the Chromatron in the United States and the rest of the world.
For Julius and Sy, this meant the end of their careers at Autometric, but by no means the end of their contributions in their respective fields of endeavor.
For Sony, this was the start of a new beginning. They knew it would be a difficult task but accepted the challenge. According to an article appearing in the German magazine, Der Spiegel, dated September 23, 1964, Sony assigned 50 members from the Research Institute to work on the completion of the Chromatron. History books tell us that Sony failed in their efforts to develop the Chromatron, but they did not fail. Their continuing work on the Chromatron ultimately led to an improved Chromatron renamed Trinitron. They corrected the Lawrence tube problems with their own ideas and Trinitron went on to be the most successful color television system in the world with a 40 year production run. Julius Shapiro and Seymour Yusem, two dedicated project engineers can be very proud of their early contributions to the project.
The (Autometric/Sony) Chromatron (Sony started development in 1961 under Paramount license) CRT has now evolved into an inline three gun CRT offering in excess of 300 foot-lamberts highlight brightness in normal operation. (A typical shadow mask CRT develops 30 to 45 foot-lamberts highlight brightness.) A slender black stripe is laid down between each color phosphor to increase contrast. The tube does away with the beam switching grid with it’s associated r.f.power which characterized the older tube. The post-deflection focusing second-anode grid is an array of closely spaced parallel taut wires located about 1/2 inch in front of the phosphors. The grid is operated with about 6 KV difference between it and the electron guns. Source: Electronics World, January, 1964.
The story continues below in my various collections and concluding with the finding of an extremely rare working Sony Chromatron in 2013.
There was another color system developed to improve upon the RCA system. Please see the Indextron page.
NEXT, A SETBACK
September 8, 1964
Sony Prototype 19 inch One Gun Chromatron
A prototype 19 inch one gun Chromatron was put into pilot production and shown for the first time at Sony corporate headquarters in Japan on September 8, 1964. There are conflicting reports that this set was a 17 inch, but the evidence presented here, indicates it was more likely a 19 inch color set. Here, a photo of the prototype 19 inch Chromatron.
Notice that it is a horizontal designed console. The first production model had a vertical console.
This image below, is believed to be the only known photo of the Sony prototype 19 inch one gun Chromatron CRT. The size conflict may have arisen because the envelope of the tube is 19 inches, but the actual diagonal viewable measurement is just over 17 inches. Sony claims a peak brightness level of 90 foot-lamberts white or about 2 1/2 times greater then the shadow mask type. The three gun version offers more then 300 foot-lamberts peak white.
Sony struggled with the manufacturing process of this set as discussed below and the one gun 19 inch Chromatron never made it to final production. The one gun with its complicated switching grids was abandoned in favor of a three gun version and the first production model Chromatron with three guns went on sale in Japan only in May, 1965.
Continuing research, in December, 1966, Sony completed a prototype 7 inch Chromatron using the just invented, right out of the lab, one gun with three inline cathodes combined with the Chromatron CRT with its wire selection grid. Now, the Chromatron was even brighter using three inline cathodes within a one gun structure, a remarkable achievement! This prototype set later made its way to final production and was introduced in the United States in April, 1968 as the model KV 7010U.
This new form of television CRT called the Chromatron was later abandoned in just three short months and a brand new 7 inch tube was substituted in the same but modified chassis and designated the KV 7010UA, christened “Trinitron”. The exteriors of the two models look identical. The Trinitron eliminated the wire grids, instead using the newly invented “Aperture Grill” which was more like the traditional shadow mask, but instead used unbroken vertical slits which allowed much more light to pass compared to the shadow mask. The Arpeture Grill was less efficient, but said to be 2 1/2 times brighter then the existing shadow mask set of the day. No doubt this was done to lower manufacturing costs and it was a device that Sony could patent and call their own.
Sony anounced the invention of the Trinitron in Japan on April 15, 1968 when they unveiled the 12 inch model KV 1310 with production availability mid October, 1968 in Japan (which is the same set as the domestic KV 1210U) but it appears that the first Trinitron, being the 7 inch model KV 7010UA went on sale in the United States prior to October, 1968. The following material below, describes in detail how all this came about.
Article about the upcoming Sony Chromatron color television in December, 1964 issue of Radio-TV Experimenters magazine. View the PDF.
1965 Sony Chromatron 19C 70 Color Television
You are looking at the world’s first mass produced Chromatron color television. What’s so special about the Chromatron you ask? Dr. Ernest O. Lawrence invented the tube in 1951. It was a single gun CRT using vertical stripes of red, green and blue on the screen much like the Sony Trinitron, now out of production due to the emergence of flat panel displays. The design patent by Dr. Lawrence, a Nobel prize winner from California, came 17 years prior to the Trinitron! Additionally it did not require a shadow mask, thereby allowing for a 75% brighter image. Behind these stripes were vertical wires which could be charged with electric current to deflect the single electron beam to each of the stripes. The tube did not require convergence circuitry, used less parts and lower power consumption. The bright color images of the prototypes looked promising, but unfortunately, Paramount Pictures, Chromatic Television Laboratories, a subsidiary of Paramount, Litton Industries, licensed under Chromatic and others failed to solve the difficult manufacturing process and a mass produced Chromatron was never brought to market until this Sony 19C 70 in Japan in 1965. A rare photo, believed to be one of a very few existing photographs of a 19 inch 1965 model 19C 70 Chromatron by Sony on display at the Sony History Museum. This model was first shown in Japan in September, 1964 as a prototype using one gun. In May, 1965 the 19C 70 Chromatron went on sale to the Japanese market only, using a delta three gun system. The chassis was not transistorized. Sony offered a unique life time warranty on it’s first color television product, if it broke, Sony fixed it for free. Only 13 to 18 thousand units were sold in 1965 and 1966 at a very expensive $550.00 American dollars, but it cost Sony more then double that amount to produce each one. The Chromatron was a unique color CRT which promised very bright images and had many technical advantages over the conventional shadow mask color CRT. It was the first Chromatron to be sold to the public, but Sony was plagued with numerous technical problems, only 2 or 3 out of 1000 on the production line were good, so Sony stopped production * in September, 1966.
Update April 24, 2015: To clarify, we now believe the production problems were not with this set, the 19C-70 delta three gun Chromatron, but rather with the pilot production one gun Chromatron which we believe never went into final production. The Delta three gun Chromatron sets, 19C-70, 80, 90 and 100 were a compromise until the Trinitron was perfected and ready for production. The Chromatron development did not die, you can read more about the Chromatron below and on the internet. Thanks to pchome.net for the photo.
* Update, July 21, 2014: Just found out from my online friend, Noriyoshi from Japan, that Sony manufactured two additional Chromatron models in 1967. They are the 19C 80 and 19C 100 both delta three gun, all tube televisions. Noriyoshi is currently repairing a 19C 100. More information to follow.
* Update August 26, 2014: My friend Jerome Halphen found this Chromatron data book which has detailed information on the Sony Chromatron 19C 70. Unfortunately it is not written in the English language. Perhaps one of my Japanese viewers could translate the following 8 pages. Thank you for the scans Jerome. The book discloses yet another Sony Chromatron model previously unknown by this author, the model 19C 90. We now have a total of four Sony Chromatron models the 19C 70, 19C 80, 19C 90 and 19C 100. The last three were manufactured in 1967. View the PDF.
NEXT, A SECOND CHROMATRON
Yaou Chromatron Color Portable
I found this photo with caption below, in the August, 1965 issue of Popular Mechanics magazine. It is also referenced in the Radiomuseum.org website and in the book, The History of Television, 1942 to 2000 by Albert Abramson. This book recites that Yaou Electric Co. of Japan produced a line sequential Chromatron with an 8 inch CRT and introduced it to the Japanese market as early as 1963. If this is true, this set could claim the title as first Chromatron to be marketed, ahead of the above Sony 19 inch Chromatron in 1965. The Popular Mechanics article states this television had a planned U.S. introduction in Fall, 1965. This photo appears to show only a VHF tuning selector, however it may have an integrated UHF tuner. If the set was marketed in 1965, the FCC required that all televisions sold after 1964, incorporate a built in UHF tuner.
Update October 11, 2013: My friend Jerome Halphen from Paris, France and his friend Noriyoshi recently visited the NHK museum in Tokyo, Japan. There, they found on display, the Yaou Chromatron Color Portable TV among other things. This model is called GENERAL TELEVISION COLORNET GTC-9.
The following is a report from Jerome:
“What we previously called the YAOU TV is in fact a GENERAL (TELEVISION COLORNET GTC-9.
Noryoshi said that he had one to repair 10 years ago and that it had a very mediocre (course) color picture. This proves that at least some where indeed sold on the Japanese domestic market.
Noryoshi also estimated the NHK date label as wrong, he said 1965-1966 which would be consistent with the YAOU text we have on the B&W only photo we had previously. Maybe 1963 was the prototype date issue and that’s why NHK labelled it so.
Another thing Noryoshi told me is that the * entire YAOU development team was poached by SONY who was then midstream between the non-working Chromatron and the not yet developed Trinitron. This would make sense as SONY surely needed to muscle its teams in color CRT technology when they were frantically trying to come up with a viable color CRT solution.
Speculation here, but if YAOU’s R&D became a hollow shell, they probably dropped the project, sold the technology to GENERAL who ultimately marketed the TV.
The schematic is very advanced for a 1965 color set. It’s entirely transistorized except for the usual 3x miniaturized EHT rectifiers. The tubes are IDK-37 or 1DK-37, probably the same as in the SONY 5″ B&W 5-303W.
It’s a cute set! i asked Noryoshi to grab one if ever he sees another. The color CRT has no reference other than COLORNETRON. It uses 14.4KV final EHT voltage and a 4.7KV to 6.3KV swinging voltage on the color selection grids.
Y Luminance is applied to the Cathode, the Color signal to the G1 Grid.”
Update December 12, 2014:
* We insert here a translation from a Japanese blog, AV and Home Theater.
“1964 /? HachiO Electric Co., Ltd. is the world’s first 9 form line sequential method All transistor color TV launched the “color net” GTC-9
Adopt a “color net” Kobe Kogyo (now Fujitsu Ten) and joint research and development the single electron gun color picture tube “color magnetron”
1965 /? Sony pulled out all the human color magnetron development department of Kobe industrial”
A few photos courtesy Jerome Halphen.
Thank you my friend Jerome and to Noriyoshi. Jerome is a long time collector of vintage television and Noriyoshi is an electrical engineer in Japan, he has his own website:
To sum up, I’m still conflicted on the introduction date, so for now, will keep this television in place. (1965) We now know it went to market in Japan therefore, all references on this site to the Sony Chromatron 19C 70 being the “first or only” Chromatron to be marketed to the public are amended. A very interesting addition to Chromatron Color CRT history.
Update October 16, 2013:
Additional research courtesy the Radio Museum revealed the following,
Yaou Radio Co ltd ; Kanagawa-ken
Yaou Electric Co., Ltd.
Yaou Electric Co.Ltd. was a manufacturer of radios and tv-sets, marked as “General” on the front.
Yaou is mentioned in “The history of television, 1942 to 2000″ by Albert Abramson : They introduced their first color-TV in spring 1963 with a line-sequential 8″ Chromatron one-gun type CRT.
It may be hard to identify “General” as “Yaou” products because the circuit diagrams inside of their radio models are issued (sometimes) in Japanese language.
Yaou Electric Co. Limited. 1116 – Suenaga Kawasaki-Shi Kanagawa-Ken Japan
I found the Patent: Application January 25, 1963 Patented February 7, 1967 Number 3,303,275. With this information, you can research the Patent on-line.
Update April 6, 2014:
I found a July, 1965 IEEE paper stating that the Yaou Colornet utilizes a variation of the Lawrence tube and was available late 1965.
Broadcast and Television Receivers, IEEE Transactions on (Volume:11 , Issue: 2 )
Date of Publication:
38 – 49
Digital Object Identifier :
Date of Current Version :
12 November 2007
Issue Date :
This confirms Noriyoshi’s belief that a 1963 release of the Yaou Colornet was incorrect.
Update, May 31, 2014. Additional details appear.
In the November, 1964 issue of Electronics World, we found the article posted below. The CRT is called “Colornetron” and is 9 inches? The new tube and circuitry is still going through the patent process and details are not available. It is revealed that this CRT uses line-sequential color generation. In this approach, the color phosphors are laid down in fine horizontal lines down the screen, unlike the Sony Chromatron.
Look at the left photo. There are small differences in the design compared to the model displayed in the NHK Museum. The handle is now a leather strap instead of a rigid folding handle. The two control knobs on the side appear to be mounted higher and the speaker grill is mounted lower. There appears to be additional “filler” material surrounding the Colornetron CRT compared to the 9 inch black and white model on the right, therefore we think this article misstated the screen size and the Colornetron CRT is 7 1/2 inches as reported above. This set still does not appear to have a UHF selector dial which was required after 1964.
Look at the next photo below. This is the 1965 Philco-Ford model N1052BK 9 inch black and white television that was sold by Ford dealerships as an accessory for the Ford Mustang. A dead ringer right down to the rocker switch and identity tag. The only difference is that this Philco model added the required UHF tuner. You can see the UHF selector on the left side of the control panel. Did Philco secure a license from Yaou Electric to market the Colornet under the Philco-Ford brand name? We do know that Philco worked for 10 years in the 1950’s to develop the beam index tube. The project was terminated without success. We recently learned that Philco was still interested in alternate color picture tube technology when in 1967, they purchased a license from Paramount Pictures Corporation to develop a Chromatron color television set. More about this further down in this article. To the best of my knowledge, the Colornet was never marketed in the United States but the remarkable resemblance to the Yaou black and white model tells me Philco may have been working on the Colornet.
Update February 28, 2015
An “Outline of Engineering Design of the COLORNET System 9 Type Color TV Receiver” by Yasumasa Sugihara, Hisao Ito and Akira Horaguchi (Yaou Electric Co. Ltd., Kawasaki. Courtesy Yaou Electric Co. Ltd. View this PDF Said to have 80% beam efficiency with 250 horizontal lines of resolution. 30 watts AC, 20 watts DC. Written in the Japanese language, your browser may ask you to download a foreign language plug in. Copy and paste the text into the Google translate app for translation.
An advertisement appearing in the December 13, 1965 issue of Electronics magazine featuring the Yaou Colornet GTC-9. Note, the photo still does not show the UHF tuner selector which was required to be included in domestic televisions sold at this time.
Established as Yaou Shoten Ltd. The company moves from the manufacture of radios, loud speakers, electric phonos, etc. into the manufacture of home electrical appliances
Company named changed to Yaou Denki Ltd. Kawasaki factory.
Company name changed to General Ltd.
Named changed to Fujitsu General Ltd.
A few new details surface about the Sony first generation Chromatron and the Yaou Colornetron in this two page article appearing in the January, 1966 issue of Radio-Electronics. View the PDF.
In 1966, Fairchild Semiconductor Co. designed this experimental 11 inch color Chromatron C6003 for Paramount Pictures. It was an all transistor set except for one rectifer tube. The details can be found here courtesy of Radio-Electronics June, 1966 issue. View the PDF.
Sony Chromatron 19C 80, (19C 90), 19C 100
* Update, July 21, 2014: Just found out from my online friend, Noriyoshi from Japan, that Sony manufactured two additional Chromatron models in 1967. They are the 19C 80 and 19C 100 both delta three gun, all tube televisions using the Chromatron wire selection grid. These two models were manufactured in 1967. The 19C 70 is also a delta three gun, all tube set. All three model use the same 19 inch CRT, 480AB22. Noriyoshi is currently repairing a 19C 100. Watch his progress here. See the below photos of the 19C 100, courtesy Noriyoshi Tezuka. More information to follow. Special Thanks to my friend Jerome for alerting me of this.
Update, July 22, 2014: A query to the Sony Archive Museum in Tokyo, Japan revealed the following:
“Chromatron color TV 19-c 80
Price:\179,000+tax (at that time)
Chromatron color TV 19-c 100
Price:\198,000+tax (at that time)”
Unfortunately, no original photos to display.
Update April 21, 2015: The Sony Chromatron 19C-80 won the Good Design Award of Japan in 1968.
This is speculation, but we believe Sony marketed the 19C 80 and 19C 100 in Japan to appease the angry Sony dealers who did not have a Sony color set to sell, (Sony’s competition were selling shadow mask color sets years earlier) even while Sony was working behind the scene to develop the Trinitron.
(The Sony KV 7010U may have been an appeasement to U.S. dealers until the Trinitron was ready. More about the KV 7010U can be found below.)
Update May 26, 2015:
This Sony 19C 100 was recently discovered May, 2015 in an online Japanese auction which is now completed. The set sold for an undisclosed amount. The following photos give us additional details about the set.
Sony Chromatron Prototype
These two images were taken from my September 1967 issue of Popular Science magazine. In the first image, Sony co-founder Akio Morita on the right is demonstrating the newly developed Sony Chromatron 7 inch color television which main advantage is a very bright image, even under bright flood lights. Popular Science magazine reports this is to be the first Chromatron sold in the United States. The set was called “Microcolor”. * I believe the article is in error, because it it was well know that Sony gave up on the Chromatron in the fall of 1966. The Chromatron had production problems, yielding only 3 good tubes out every thousand. It sold for 198,000 yen ($550.00) in Japan, but cost Sony 400,000 yen to build each set. In Japan, plagued with problems, Sony sold only 18,000 Chromatrons from 1965 to 1966. (Information from the book “Sony”) I believe this television is a pre-production version of the 7 inch Trinitron introduced by Sony in 1968 and discussed below. You can see differences in the control arrangement, the carrying handle and smaller trim pieces on the sides from the final production version shown below.
* Update: The below images are indeed that of a Chromatron, however a modified redesign of the Chromatron. Because of the overwhelming problems of Sony’s Chromatron in Japan, financial losses from the Chromatron development and mounting pressure from Sony dealerships to introduce their first color set, Sony’s chief engineer and CEO launched an aggressive campaign to develop a new color tube. Sony took inspiration from the 1966 General Electric (GE) Portacolor and considered licensing the design, but in the end insisted that they design a new CRT which had the Chromatron benefits of high brightness. Early RCA color CRT’s and shadow masks blocked as much as 85% of the light energy. The Portacolor had a unique 3 beam, 3 gun, inline color CRT, but Sony engineers devised a way to create 3 inline beams within one gun for the first time. The three electron beams focused through the center of a newly developed single large lens instead of through three small lenses. This resulted in a much improved, focused image in the same way as a photographer closes the aperture of the lens, using just the center of the lens to obtain the sharpest image. The center of the lens is the sharpest. A side benefit is fewer convergence adjustments. In December of 1966, Sony developed the 7 inch Chromatron prototype as pictured below. Sony had to work out additional technical problems with the Chromatron, and it’s engineers worked day and night to meet a self imposed deadline: SUCCESSFULLY DEVELOP A NEW COLOR CRT FOR MARKET RELEASE BY OCTOBER 1968. They created a new type of shadow mask which had unbroken vertical slots or stripes instead of the round holes of a conventional shadow mask, allowing much more light to pass through. Sony called this mask the “aperture grill”. On the evening of October 15, 1967, the new tube, with the inline 3 beams, 1 gun, lens and aperture grill were assembled and tested. It was a success and a new color tube was born and named “Trinitron”. “Trini” for 3 electron beams, “tron” from Chromatron the original inspiration. On April 15, 1968, the Trinitron color television was announced at Sony corporate headquarters. Trinitron is the son, born from the Chromatron and the first color set to go on sale in the United States was the 7 inch KV 7010U Chromatron, followed shortly with the KV 7010UA which swapped out the Chromatron with the new Trinitron CRT, which is very similar to the Chromatron prototype as below. I wish to credit Sony and the author of the book “Sony” for some of this information. This writer had just graduated from high school in January, 1965 and went directly to work in his new career. I wanted to purchase my first color set in 1966. I spent months of evaluation on the color televisions available at that time. Zenith, Motorola, Magnavox, Slyvania, General Electric, RCA, Admiral, Packard Bell, Curtis Mathis and others were evaluated. Eventually, settled on the RCA as shown above, but was not satisfied with it. After seeing the first two Sony sets, a 7 inch and a 12 inch in 1968, I looked no further. They had the best color imaging available at the time and blew everything else away in my personal opinion. It was to me, a quantum leap improvement in quality.
Update July 11, 2012: I am now convinced that the below two black and white images are not that of a true Chromatron. Why? I recently acquired a copy of Sony’s 1967 annual report. Sony states that the below television is a Chromatron and was shown in the United States in June, 1967 and would be marketed in the United States in summer, 1968. We know that Sony gave up on the Chromatron in Japan in 1966 and set out to re-engineer the tube. We are looking at a modified Chromatron television in the two photos below which is the Trinitron. Sony called it a Chromatron in the Popular Science article and in their annual report, because it was not officially named a Trinitron until their April, 1968 announcement. You can see that in the 1968 color publicity photo, it was called Micro Color same as the prototype in the two black and white photos from 1967. You can see that the color 1968 publicity photo is virtually identical to the final released version of July, 1968, which was called a Trinitron.
* Update January 28, 2013: I was wrong. Just found a working Sony KV 7010U Chromatron! The set is being repaired and I will provide detailed information and photos soon.
After the Chromatron, nineteen years later, Sony succeeded in developing the first commercially available index beam television in the form of a one tube projection TV and rightfully renamed it the Indextron. After that, three years later in 1988 the first stand alone consumer available beam index color television called the WatchCube. You can read about it on the INDEXTRON PAGE.
The integrated antenna/handle design was carried forward in the 5 inch Sony Trinitron KV 5200 introduced in 1980 and shown on Page Two.
Sony’s Official Description Of The Problems Encountered Developing Chromatron.
Quoted directly from Sony’s History Website, Courtesy Sony Corporation.
“Overshadowing the exciting news of the Sony Building and successful foreign investment bids were the diligent efforts of the Chromatron development team.
Completed and announced to the public in September 1964, the Chromatron color TV was displayed at the Sony Building and was the focus of much attention. Nonetheless, mounting production costs and its tendency to malfunction made mass production unfeasible.
Numerous practical problems not addressed in Dr. Lawrence’s theory arose when producing an operational model. These included troubles derived from the use of high voltage and difficulties in insulating against it. The scanning stripes, which make up the fluorescent screen, must be so thin as to not be detected by the naked eye. At least 270 to 300 stripes are needed for picture resolution. When compressing the stripes, however, the space between the color switching grid wires must be proportionally narrowed. The precision needed to focus the electron beam through the narrowed grid requires high voltage. This, in turn, requires high performance insulation, which is technically difficult. Naturally, the insulation material must tolerate high voltage. The problems involved in determining what materials to use for insulation and how to affix it were not easily resolved. Since the insulated parts were set inside the cathode-ray tube, there were problems creating and maintaining the proper vacuum level inside the tube. The more tests they ran, the more problems they incurred.
To double the brightness of the picture, the development team devised aluminum film for the back of the fluorescent material. Due to high voltage, however, the thin aluminum film was often drawn toward the color-switching grid. As a result, the display would show dark spots in places where the coating had chipped and glittering patches where it had stuck to the grid. Eventually, as large sections chipped off and stuck to the grid, it would short circuit and the switches would stop functioning. Such electrical defects developed one after another.
To compound matters, etching the phosphor was much more difficult with Chromatron than with the shadow mask process. Compared to the optical printing method of the shadow mask process, which etched the phosphor stripes using the rectilinear propagation characteristics of light, the electron beam printing method used in Chromatron involved etching after the cathode-ray tube was assembled. This was extremely time consuming — in all, one phosphor stripe alone required from forty minutes to an hour to etch. Thus, even if a printing machine was in full operation 24 hours a day, it could only print 24 stripes a day. In order to meet demand within the eight hour working day, Sony would have to buy dozens of printing machines. In any event, it was not a very productive process.
There were no simple answers, research expenses continued to mount. Yoshida, Miyaoka and Ohgoshi, leaders of the Chromatron team, went through one difficulty after another. At this rate, Sony would never claim Chromatron color TV as its fifth innovative product. In fact, those involved considered it more of a “kuro-matron” than the Chromatron, “kuro” meaning struggle in Japanese,.
“Are you sure that the shadow mask doesn’t deserve reconsideration?” Ibuka suddenly brought this up at a board meeting. It seemed that the ever confident, resolute Ibuka had nearly lost hope. The Chromatron situation was that serious.
The more Chromatron sets they made the greater their losses. Pouring any more funding into the development of Chromatron seemed concomitant to “shinju” or double suicide.
“This is all my fault.” As president, Ibuka blamed himself for the Chromatron fiasco. Nonetheless, Ibuka had his pride — not so much as a businessman, but as an engineer. Now, if ever, was the time to back up his dejected engineering staff.
“Start looking for a process to replace Chromatron. This time I will act as team leader from start to finish.” This was Ibuka’s way of taking responsibility.
Morita provided vital support. He told Ibuka, “Don’t worry about funding. I will take care of it. Develop the project exactly as you wish.” From that day fourth, Ibuka went to the laboratories daily to oversee the new project.
In the summer of 1966, Yoshida went to the U.S. to research the market and to inspect the portable color television which General Electric had announced the previous year. This 13-inch set used a shadow mask system with three electron guns in-line. Yoshida received some inspiration from it, but decided that its technology could not easily be applied to sets larger than 13 inches. Yoshida found RCA’s advances even more startling. The brightness of their picture had greatly improved. This was due to the switch in fluorescent material from sulfide to rare metals. In addition, RCA was producing about 20,000 sets per month. Yoshida was amazed, especially considering the production rate of 1,000 a month at Sony. In his consideration, RCA’s set was a perfected product.
“If we can’t begin mass production by 1966, then we’ll have to give up the Chromatron and switch to the shadow mask system.” Upon receiving Yoshida’s report, Sony top management reluctantly gave the okay to consider the switch to the shadow mask process.
Yoshida, however, could not bear the thought of bowing to RCA’s technology. Nor did he intend to let the five years of hard work that the staff had devoted to Chromatron amount to nothing. There had to be some solution to this dilemma. Just when everyone else had given up hope, Yoshida offered a gamble of an idea in sheer desperation.
Taking a hint from GE’s portable TV, Yoshida suggested reforming the electron gun. “See if you can run three electron beams through a single electron gun.” The Sony staff was cool to the idea. It seemed from the beginning nothing more than an experiment to prove the futility of the idea. Miyaoka was among those who wondered whether “Mr. Yoshida had gone nuts.” Miyaoka grudgingly ran the experiment, in part, simply because it was an order from the top.
Common sense said it was impossible. But the results contradicted this. Upon hearing the results, Ibuka thought, “This sounds as though it’ll work! I think we should go with it.” Ibuka immediately called Miyaoka to ask whether he considered the new gun viable. Miyaoka really was not sure. On this day, however, he had a special reason to reply in the affirmative. Miyaoka was an avid cellist, and it was his rehearsal day. Any answer other than “yes” would have tied him up answering Ibuka’s questions and make him late for practice. So Miyaoka answered “yes” and left for practice.
In December 1966, the prototype of the new electron gun was completed. The test results on a seven-inch Chromatron set were startling — it gave the sharpest picture yet. With this, future prospects finally brightened.”
Authors Note: We believe the above mentioned seven-inch Chromatron is the prototype set shown just above in the 1967 issue of Popular Science magazine and as you will see later, went to final production in April, 1968 as the model KV 7010U. Yet, we have documented evidence that while the KV 7010U went to commercial market in April, 1968, almost immediately according to the April 29, 1968 issue of Electronics Abroad magazine, Sony decided to drop production of the KV 7010U and beginning in June (1968) start shipping the set with the Trinitron CRT, model KV 7010UA. For this reason, we say the KV 7010U was in production for three months or less. You will see further on in this article and on the Vintage Micro TV page, that my Chromatron KV 7010U is unit number 523. We know of another set, KV 7010UA which has a Trinitron CRT and it is unit 1584. That is a difference of 1061 units. Sometime after unit 523 and before unit 1584, Sony dropped the Chromatron CRT and switched to the Trinitron CRT.
“Next Ibuka and his team tested the effect of the new three gun in-line system on a shadow mask screen. The results were excellent. They worried, however, that using this with the shadow mask would dominate the new technology they had developed. Or worse yet, the new system might underscore their failure with Chromatron.
There had to be some way of incorporating the shadow mask’s merits into a process that provided even better quality than with the shadow mask done. Their reputation as innovators was at stake. Once again the entire engineering team gathered for days of brainstorming sessions. Despite his confidence in his engineers, Ibuka secretly worried whether it was not smarter to accept defeat and resort to another method. Before his troops, however, he remained dauntless and confident, always giving encouragement and inspiration.
Ohgoshi provided a needed breakthrough — the concept of the aperture grille. This grille consisted of narrow vertical stripes photo-etched onto a thin metal plate that was stretched over a frame. The electron beam penetration rate was 20%, a large improvement over the shadow mask’s 15% penetration rate. And the woven grille resembled the Chromatron. It was a lifesaver. Or so they thought for a short while.
Once again, problems appeared in the application stages. Due to the vibrating metallic tape in the aperture grille, the electron beam could not find its target. This resulted in uneven color. Ibuka, however, pulled Ohgoshi from this pinch. He merely stretched a couple of tungsten wires across the grille — a simple solution, but it did stop the vibrations.
Ohgoshi also took on the job of designing the glass envelope for the cathode-ray tube, by molding a model from gypsum. Usually a blueprint would be sent to a professional component company, but Ohgoshi insisted that it was simple enough to do by himself.
On the evening of October 15, 1967, the completed glass envelope was delivered to the plant. The research room was humming with activity — they were about to assemble the new cathode-ray tube. Each group of engineers worked silently on their allotted assignment: integrating the electron gun, affixing the aperture grille, applying the fluorescent material to the screen, etc. Finally, after degassing, the new cathode-ray tube was completed. By then, dawn was on the horizon.
After connecting the electrical circuits, a new color television was born. After final adjustments, it was finally tested. The incredibly bright screen overflowed with dynamic color. Everyone could only stare at the screen in silent amazement. Ibuka and top directors came running upon hearing the news.
“Everyone, it was quite a struggle, thank you…” Ibuka wanted to offer more words of encouragement, but could not. They had finally reached the end of a long and winding road. The new color television was named Trinitron — a compound derived from “trinity,” meaning the union of three, and “tron” from electron tube.
On April 15, 1968, The Trinitron was announced at a press conference at the Sony Building, where the reaction of both foreign and Japanese reporters was better than expected. At the end of the news conference, Ibuka made a comment that no one expected. “Trinitron will go on sale in mid-October, and by the end of the year, we’ll produce 10,000 sets.”
The research team member stood there stunned. No one could believe what was just said. They had just finished producing a mere 10 test models. How could they shift to mass production in less than half a year?
I’d like to wring his neck…” Yoshida scowled menacingly at Ibuka.
Ibuka, apparently heedless of the feelings of Yoshida and the others, assumed a look of nonchalance. His expression seemed to say,”I know you guys can do it.”
An article appearing in the January, 1968 issue of Electronics World magazine.
Sony KV 7010U Production Timeline Approximate.
December, 1966: Completion of prototype 7 inch Chromatron with first use of the one gun, three cathode system combined with the Chromatron wire selection grid.
Early, 1967: The new one gun, three cathode system is tested with a shadow mask, results reported to be excellent.
Mid, 1967: Concept of the Apeture Grill is devised.
June, 1967: The Sony prototype 7 inch “Micro Color” Chromatron is demonstrated to the press in New York City. Morita announces this set will go on sale in the United States in Spring, 1968.
October 15, 1967: The first prototype set combining the one gun, three cathode system with the Apeture Grill is assembled and tested successfully.
April, 1968: Morita and Ikuba announce in Japan, the invention of the Sony Trinitron Model KV 1310.
April, 1968: Gulf Western, parent company of Paramount Pictures Corporation, announces the 7 inch Sony “Micro Color” KV 7010U one gun, three cathode system with Chromatron wire selection grid, will go on sale in the United States in April, 1968.
April 29, 1968: Sony states, reported by Electronics magazine, that they will stop production of the KV 7010U Chromatron and beginning in June, 1968 start shipping the new 7 inch KV 7010UA with Trinitron CRT.
About August, 1968: Sony KV 7010UA Triniton go’s on sale in the United States.
This 1968 Sony publicity photo with live screen shot appears to be Model KV-7010U. It was photographed from my copy of the December, 1968 issue of Popular Mechanics. This is the earliest production model, later changed to the Model KV-7010UA with minor changes. This photo shows “Micro Color” with no three-color logo above the viewing screen. The sales brochure below, shows “Trinitron Color” with rectangular three-color logo above the viewing screen. A later version changed the three-color logo to the ellipse design.
Some interesting information can be gleamed from the magazine article.
1. The set is described as “Micro Color” not the Trinitron.
2. A diagram of the CRT shows a wire grid and described as such instead of the Aperture Grill.
3. The text of the article says “it has a grid of fine wires that give the tube high transparency.”
4. The article describes the CRT as being an “improved Chromatron developed by Dr. Lawrence.”
5. The article states “Sony took the Chromatron and added a raft of improvements that licked the production problems … and christened the tube Trinitron”.
6. The article further states “Sets currently on the market carry a list price of $429.95.”
This December, 1968 issue hit the news stands in November and we know magazine articles are usually prepared a month or two in advance of publication. Given that, we can say this particular model was on the market at least as early as September or October, 1968.
Question? Is the magazine article reviewing the KV 7010U Chromatron or the KV 7010UA Trinitron? I know of one set owned by a collector which is designated “Micro Color” without the three color logo, but is confirmed to be model KV 7010UA with a Trinitron CRT inside. Curiously in the October 31, 1968 Sony Annual Report, Sony states that a 7 inch Micro Color television was marketed in the United States July, 1968. They are silent as to whether it was the Chromatron or the Trinitron, but interestingly, in the previous year Sony Annual Report dated October 31, 1967, they stated that “a 7 inch Micro Color Chromatron will be marketed before Summer, 1968.”
Update, June 19, 2014: A careful examination of the photo in this magazine showing the rear identity tag reads ” Transistor TV Receiver”. This confirms that the TV under review was a KV 7010U Chromatron and because of the recent find of the KV 7010U service manual and other information recently found, we are now convinced that the author of this article was auditioning and reviewing a Sony Chromatron KV 7010U. The service manual recites: “7 inch, 90 degree deflection Chromatron system incorporating “Trinitron”. We now know that the KV 7010U Chromatron was released April, 1968 and the KV 7010UA was released approximately 3 months later.
As you will see below and on page one, Vintage Micro Television of this site, I found an actual Sony Chromatron Model KV 7010U.
(Note: We are showing information on the Sony KV 7010UA because it’s an improved Chromatron, renamed Trinitron and because cosmetically it looks identical to the KV 7010U except for the the identity tag above the screen. In fact, the very first production run identified the KV 7010UA as “Micro Color” and later “Trinitron Color”. The only way you would know the difference is by looking at the tag placed at the rear of the set. The photo on the right shows that this set is a KV 7010UA Trinitron Receiver. On a KV 7010U, the tag reads “Transistor TV Receiver” Model KV 7010U) This tag shows the Chromatron identity.
Sales Brochure from 1968 of the worlds smallest color television. In April, 1968, Sony introduced their first Chromatron and soon thereafter (July) Trinitron color TV for the U.S. market and the world’s smallest color TV at the time. It had a revolutionary new 7 inch CRT described in detail on PAGE ONE.
This is an original four page sales brochure of the first Sony Trinitron television sold in the United States, the seven inch KV 7010UA. It became available for sale in the Summer of 1968. I purchased new in spring of 1969.
Scans of vintage analogue 35 mm color print photographs taken shortly after acquisition of my original Sony KV 7010UA purchased in 1969.
Live Screen shots from the moon photographed August 2, 1971 taken off the Sony KV 7010UA. The mission, Apollo 15, carried two astronauts, Commander David R. Scott and LM pilot James B. Irwin, the seventh and eighth men to walk on the Moon. These images are photos of the actual 35mm color prints I took on that day.
Two digital photos of original analogue 35 mm prints photographed 1971. Actual screen shots off the Sony KV 7010UA from the Tonight show in 1971, the first Carol Wayne, the second, George Burns. The original images were much sharper, these shots are photographs of photographs. Keep in mind these images were produced with 42 year old studio cameras, since then technology has progressed considerably. Having both the KV 7010UA and the KV 1210U in my possession at the same time, I will say the 1210U had a brighter, better focused image. I started taking screen shots back in 1969, being impressed with the picture quality of the Trinitron system.
Original Sony KV 7010UA 4 color service manual, block diagrams, wave forms, etc. Drop me a line if you would like a copy.
In 1967, Sony demonstrated a 7 inch Chromatron prototype according to a Sony press release on June 20, 1967. In Sony’s Annual Report dated October 31, 1967, Sony stated that a 7 inch Chromatron would be marketed in the United States before the Summer of 1968 and in Sony’s Annual Report dated October 31,1968, Sony confirmed that a 7 inch micro color was marketed in July, 1968. It appears that prior to the launch of the famed Trinitron CRT, an actual hybrid Chromatron with a 7 inch CRT was introduced in the United States as the model KV 7010U and then quickly replaced (within 3 months) by the model KV 7010UA with a Trinitron CRT. In January, 2013, a working Sony KV 7010U was found by this editor, currently in his possession and confirmed to be a hybrid Chromatron 7 inch CRT. The television was opened and among other things, a label was attached to the CRT bell reciting “SONY CHROMATRON Licensed under Patents of Paramount Pictures Corporation”.
A bit of mystery surrounds the introduction of the Sony KV 7010U Chromatron in April, 1968, only to be replaced so quickly (July, 1968) by the KV 7010UA with Trinitron CRT.
*Update February 17, 2014:
Broadcasting Magazine January 15, 1968, reports: Gulf Western parent company of Paramount Pictures Corporation, holder of the Chromatron patent announced that Sony Corporation of Japan, would begin selling a 7 inch Chromatron color television in April, 1968.
In the the April 29, 1968 Volume 41 Number 9 issue of Electronics Abroad magazine it is reported that Sony has decided to drop the Chromatron CRT from the Sony 7 inch television and starting in June, 1968 would instead begin shipping a set “useing a tube right out of the laboratory” (the Trinitron model KV 7010UA). The reason given was that the one gun Chromatron requires hard-to-make color switching grids.
Update March 26, 2014: I think we solved the mystery. Sony’s purchase of a Chromatron non-exclusive license with Paramount Pictures read in part: to provide “technical assistance in the production of a chromatron tube and color television receiver utilizing it.” (Source, Sony History website) If we can find and read the entire agreement, we may find that Sony was contractually obligated to manufacture a Chromatron for the United States market and share technical information with Paramount who we know wanted to license to other U.S. manufactures.
Sony quietly dropped the Chromatron tube within 3 months of introduction and re-engineered the KV 7010 chassis with the Trinitron tube. (Source, Broadcasting Magazine)
NEXT, CHROMATRON FOUND
Sony KV 7010U Chromatron also known as the Chromagnetron
Probably the rarest and most intriguing television in my collection, combining the Trinitron one gun with the Chromatron wire selection grid CRT. The complicated and troublesome color switching is eliminated, however PDF or post deflection focus of the three cathodes is retained.
Quoting Electronics World magazine, JANUARY, 1968: “The Chromatron used in the new Sony color receiver has three color guns, but uses them to form one beam. That beam is switched at a 3.58-MHz rate which offsets it just at the moment it crosses each stripe, so that the beam strikes and activates only the colors contained in the chroma signal”. Quoting another magazine, Radio-Electronics, January, 1966, “The Chromatron uses three electron guns, not in a different principal of operation, but simply to increase available electron current and brightness. So, in a literal sense, the present Chromatron (being at the time, the prototype 7 inch set) is a single beam, three gun tube”.
Note, these two magazines are commenting about the prototype 7 inch Chromatron. We know with some certainty, that the KV 7010U has a one gun, three inline cathode tube or Trinitron, combined with a Chromatron color wire selection grid. When the magazines talk about “the three guns are used to form one beam”, or “is a single beam, three gun tube” seems puzzling. We have observed on the KV 7010U chroma video board, there is a 3.58 MHz Xtal present which is not on the KV 7010UA Chroma board, but the complicated switching appears to have been eliminated. We would appreciate reader comments.
Trinitron one gun, three inline cathodes with Chromatron wire selection grid CRT. Technically know as the * Chromagentron, but referred to in the press as Chromatron. Since we have learned that the previous Sony Chromatron’s marketed in Japan (19C 70, 19C 80, 19C 90 and 19C 100) all had three gun delta CRT’s, this Sony KV 7010U is the purest in concept to the original one gun without shadow mask prototype Lawrence Tube or Chromatron.
* Chromagnetron described in Electronics magazine, April 29, 1968, Electronics World July, 1968, The History Of Television 1942 to 2000 and in New Scientist magazine.
Update January 16, 2013: I finally found a replacement model after a 4 year search. My original model the KV 7010UA, was given mistakenly to Goodwill by my wife. The KV-7010U is the earliest production model using a Chromatron CRT and later modified by the Sony KV-7010UA with minor cosmetic changes, and swapping out the Chromatron CRT for the newly developed Trinitron CRT. See page one of the timeline, “Vintage Micro TV” for the story, then come back here for repair information.
February 14, 2013:
I asked Andy Cuffe who recapped my two Indextrons to try and restore the Sony KV 7010U.
When found, it had a blue screen with no image and static sound. Because a name and address sticker was placed on the bottom of this set, we were able to find the original owner who was a Doctor who practiced in mid town Manhattan, New York City. He used the set in the waiting room of his office. It was used extensively every day. There is more to this story which will be told later. After opening the cabinet, it was a great surprise to see this:
A Sony Chromatron licensed under patents of Paramount Pictures Corporation! I was estatic. Prior to this time, a Chromatron in a U.S. production KV 7010U was rumored but never verified to my knowledge. I have never seen a single piece of information to verify this other then Sony’s 1967 Annual Report which stated that a 7 inch Micro Color Chromatron would go on sale before the Summer of 1968 and a photo of a prototype was published in a Popular Science September, 1967 issue.
After Andy’s examination, he wrote: “This is just speculation,
but I think instead of an aperture grill it uses fine wires to focus
the beams onto the correct phosphor stripes. I expect that there is a
pair of fine wires running vertically behind each set of three
phosphor stripes. The wires form a lens that focuses the beams onto
the correct phosphor. It would need a second HV supply because there
needs to be a difference of maybe 500-1000v between the adjacent
After further examination Andy wrote:
“I can’t see much inside the CRT, but there is a small gap where there is clear glass near the front of the CRT. You can see a little of where the aperture grill would be. It looks very similar to an aperture grill, but the wires are much finer. I will try to photograph it, but I don’t think it will turn out because there are a lot of obstructions and the glass isn’t completely smooth.”
“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. This
is simpler than trying to switch a single beam from stripe to stripe.
Since the wires focus the beams onto the correct stripes (rather than
just blocking them from hitting the wrong ones) it should make the
I found the Sam’s folder for the 7010UA which has lots of pictures in
it. Most of the boards look identical. The HV circuit lacks the second
HV rectifier, and the CRT bell is a different shape. It also has a
standard set of purity rings instead of the electronic control. The
purity control on your set is probably varying the bias on the wire mesh.”
Andy performed a test on the CRT and found all three beams weak, the red especially so. Andy said a good beam emission should test at .85 on the meters, see next photo:
“I’ve fully recapped both the main circuit boards, and the picture has improved (see the attached screen shot). I still need to replace a few more caps on the main chassis, but probably nothing that will make much difference the picture.
The severe color noise is gone, and the picture has better contrast. There’s still virtually no red though. Each color has two controls. Background works like the brightness control, and drive works like the contrast control. I have the red drive and background controls at maximum. The green drive is at minimum, and the blue drive is turned up just enough to balance the green. The blue and green backgrounds are set to produce proper black level. I think this is about as good as it will get with the bad red gun. I could try to rejuvenate just the red. The red is so bad that I think it will either do nothing at all, or improve it slightly. The only risk is that something unforeseen could happen to the blue, or green in the process.
I suppose if you’re really serious, you could see if RACS in France can rebuilt it. It would be similar in complexity to rebuilding a 15GP22 (minus the leaking problem).”
We decided against rejuvenation, deeming it to risky with little chance of improvement.
46 capacitors were replaced.
The next series of photos (a summary of 178) were taken by Andy in his shop except the last screen shot taken by this author. I have many more to numerous to post, but if you are interested, I can send you full size, detailed images, just drop me a line.
Tap or click on next image for full view
Update April 19, 2015: A video of the Sony KV 7010U in operation yesterday. Watch now.
Sony service manual found by Andy Cuffe on June 14, 2014. Tap or click on image for enlarged view or view the PDF.
I want to thank Andy Cuffe for his expertise and help in restoring this television.
Now you can read about the design of the 1965 Sony Chromatron 19C 70 in the below 15 page PDF file. Some of the information applies to the design of the Sony KV 7010U. I want to thank the staff at Sony Archive History Museum in Tokyo, Japan for sharing this document. I know it will be of interest to television and history enthusiasts worldwide.
Click or tap on below image to view PDF.
Now jump back to the Time Line on page one “Vintage Micro TV” to read the story with photos and screen shots of the Sony KV 7010U.
This New York Times article dated September 9, 1964, corresponds to the above Sony press release, courtesy New York Times.
The one gun 17 inch Sony Chromatron went into pilot production. * In 1965, the following year, Sony decided to market a 3 gun, 19 inch Chromatron. This set sold in Japan only, during 1965 and 1966, and shown above on this page, as model 19C 70. Also, it is widely reported that this model sold only 13,000 units. I found a 1994 IEEE interview with one of Sony’s chief engineers of the Chromatron/Trinitron, Susumo Yoshida, which said, in part: “It was beautiful. The Chromatron is beautiful, bright, and sharp, if it works. If it can be mass-produced, it is a fantastic product. They only produced EIGHTEEN THOUSAND SETS, and it was nice, bright, clear, and sharp. People really appreciated the product. There was even a lifetime guarantee by the Sony Corporation. If it was broken, customers could ask Sony to fix it for free.”
What we have learned is that Sony continued to have technical problems. It was a manufacturing nightmare and nearly drove Sony to bankruptcy. Masaru Ibuka, Sony’s co-founder and President refused to give up on the Chromatron. He did not want to copy RCA’s shadow mask system, which he deemed inferior. “We must produce something different. We do not copy … We are a company of engineers.” Indeed it was written in the company’s founding prospectus which Mr. Ibuka drew up in 1946.
Mr. Ibuka finally thew in the towel in Fall, 1966. He looked for a new solution to the Chromatron, and assembled a core group of engineers who were given the task of correcting the Chromatron’s problems. They worked 24/7 and experimented with various techniques. This led to the developement of the Trinitron CRT. In many ways, the Trinitron resembled the Chromatron. It had one gun, but this time with 3 inline beams within the single gun structure. It had the vertical phosphor stripes etched across the screen like the Chromatron. The new “Aperture Grill” was aligned with unbroken vertical slits, much like the Chromatron’s wire selection grid. The Aperture grill was not as efficient as the Chromatron wire selection grid, but still was 3 times brighter then the shadow mask dots and holes system. The Trinitron required only 2 convergence adjustments, instead of the 12 used in the shadow mask system. This made the Trinitron an instant success, together with superior beam focusing through one large lens instead of three small lenses, less parts, and lower power consumption. The superior image was instantly recognized by all who saw it for the first time.
Some will say, that if Sony does not copy, well then why did they introduce the Lawrence Chromatron? Possibly one could say they imitated, and brought to consumers the Chromatron system, which no other company was willing or able to achieve before them. That was approximately *18,000 units brought to market with a lifetime guarantee, not to mention the Chromatrons sold in the United States as the KV 7010U. This led to a very similar Trinitron CRT becoming the most successful color television in history with a 40 year production run.
Update July 21, 2014: *It is unclear if the total production of 18,000 units represents the production of only the 19C 70, or the combination production of the 19C 70, 19C 80, 19C 90 and the 19C 100. The 13 to 18 thousand figure came from research on the 19C 70 which was manufactured 1965 and 1966 in Japan only. The 19C 80, 19C 90 and 19C 100 were manufactured in 1967 with an unknown production run, therefore the total production of Sony Chromatrons could be much higher then the 18,000 figure.
* Citation: It is noted that the original Lawrence Chromatron CRT was specified in both one and three gun versions. “Described in this paper is a single gun and three gun version of a simple color cathode-ray tube developed by Chromatic Television Laboratories, Inc., based on the ideas of Dr. Ernest O. Lawrence of the University of California. Both types utilize post deflection focusing (PDF) and acceleration as will be discussed in the body of this paper. The principles described are quite general and may be applied to other cathode-ray tube and camera tube designs. The single and three gun types discussed below will operate with any of the presently proposed color television transmission systems.”
Proceedings of the IRE (Volume:41 , Issue: 7 )
Date of Publication: July 1953
851 – 858
Digital Object Identifier :
Date of Current Version :
08 January 2007
Issue Date :
NEXT, LEGAL BATTLE
On January 27, 1969, Gulf Western Industries, who purchased Paramount Pictures, sued Sony for alleged failure to share technical information pursuant to the 1964 license agreement and also on the Trinitron. (In 1961, Sony secured an exclusive license to develop the Chromatron in Japan only. In 1964, Sony obtained a non-exclusive license for the rest of the world.) We reviewed the case in the U.S. District Court Southern District of New York and read the Complaint and Sony’s Answer. Sony alleged that Great Western breached the Agreement by licensing the Chromatron Patents to Philco-Ford in 1967 without notice to Sony per the 1964 Agreement. Both the 1964 and 1967 Agreements were made part of the case as exhibits. The case was settled and discontinued with prejudice by both parties, by Stipulation filed December 9, 1969.
The 1964 license agreement did not contractually require Sony to manufacture a Chromatron in the United States or anywhere else as I had speculated.
The 1964 license agreement outlined that Paramount would be keeping track of the numbers of Sony Chromatrons sold for royalty purposes. Today Viacom is the successor in interest to Gulf Western and Paramount Pictures is a division of Viacom, so we may find the actual production numbers of the Sony KV 7010U (which I suspect is less then 1000 units) if we are allowed to check the archives of Paramount Pictures Corporation.
Interesting to note that Philco proposed another one gun system called the Apple tube now known as the Indextron in the early 1950’s. They worked on this tube for over 10 years without success.
So in 1967, Philco was still interested in an alternative to RCA’s shadow mask system, this time working on the Chromatron. I had not known this until reading the lawsuit.
In 1951, Dr. Lawrence invented the Chromatron and said the Chromatron could be marketed as both, one and three gun versions. He said the three gun would be brighter and partnered with Chromatic Television Laboratory. Paramount Pictures Corporation, holder of the Chromatron patents, never intended to produce the Chromatron on their own, rather they tried licensing deals with American and Dutch companies. None of these companies were successful in bringing a Chromatron television receiver to the consumer market until Paramount entered into an agreement with the Sony Corporation of Japan.
In September, 1964, when Sony announced to the world that they were ready to market the first Chromatron television receivers they announced the three gun 480AB22 CRT and described it as a “high class, highly luminous” CRT and simantantiously, they also announced and demonstrated a prototype one gun Chromatron CRT without a model number and described this CRT as a common class, affordable CRT. The next year in May, 1965, Sony introduced the company’s first color television receiver. It was the model 19C-70 delta three gun Chromatron using the 480AB22 CRT which sold only in Japan in 1965 and 1966. Then in 1967, they introduced three more delta three gun Chromatrons, using the same CRT, models 19C-80, 19C-90 and 19C-100. These four models were in my personal opinion compromise solutions. They required the conventional convergence boards as in shadow mask television sets. They did offer superior, highly luminent images because of the high transparency of the Chromatron wire color selection grid.
From the very beginning, Sony tried to perfect the one gun Chromatron that was demonstrated at the September, 1964 press conference and which went into pilot production, but not final production. This is the set that gave them all the problems and nearly bankrupted the company. This is the prototype set that received all the press. Sony gave up on this prototype in mid 1966 and set about finding an alternative which ended up being the famous Trinitron.
Curiously, an engineering prototype 7 inch color set, using the newly invented one gun, three cathode tube, combined with the Chromatron color selection wire grid, actually made it to the American market in April, 1968. This was about the same time as the Trinitron announcement in Japan in April, 1968. This 7 inch Chromatron was model number KV 7010U. Within approximately one month, Sony decided to terminate the KV 7010U Chromatron and shortly thereafter, introduced a near identical set, but instead, it used the newly invented Trinitron CRT, model KV 7010UA. This was the first Trinitron sold in America and appears to have come to the market just prior to the first Trinitron (KV 1310) announced for sale in Japan in October, 1968.
The Sony KV 7010U, a most interesting engineering curiosity that somehow made it to the American market and then, quickly terminated.
At the dawn of color broadcasting in 1953, the Chromatron CRT was one of the competing systems along with CBS and RCA. RCA won the competition with it’s compatible color dot and shadow mask system and introduced it’s first color television, the CT-100 in April, 1954. Ironically 14 years later, Sony introduced the Trinitron system very similar in concept to the Chromatron and in doing so, they filed more then 100 new patents to perfect and improve upon the original Chromatron. Sony achieved their goal and created a unique television technology which dismissed the licensing rights which Sony would have been required to pay to the inventors of the three gun shadow mask and Chromatron systems. This system was instantly recognized by all who first saw it as superior, it was rewarded with an Emmy award and became the the most successful television product in the world with a 40 year production run. After pioneering the color television industry, it was sad to see the demise of RCA in 1986. The Radio Corporation of America deserves great credit for all their endeavors and *inventions to enhance the entertainment experiences of the American people and abroad.
DID RCA INVENT ELECTRONIC TELEVISION?
* Actually for history, Philo Farnsworth was awarded priority of inventions for both his image dissector, (1930 and confirmed in 1934 after all appeals by RCA were overturned by the appeals courts and the Supreme Court) dating back to 1927 and the image orthicon (1933) by the U.S. Patent office. Because RCA was determined to go forward with the commercial manufacturing of television equipment, RCA reluctantly entered into a cross-license/royalty agreement with Farnsworth in 1939 after their loss in court, spending years of litigation fighting Farnsworth’s inventions. Farnsworth was honored at the 2002 Emmy Award Show in this clip. In March, 2013, Philo Farnsworth was posthumously inducted into the Television Hall of Fame by the Academy Of Television Arts & Sciences for his invention of the all electronic television. His likeness is memorialized at Statuary Hall at the U.S. Capital Building, Washington, DC.
WHO WAS PHILO T. FARNSWORTH?
The vision for electronic television came to him as a 14 year old farm boy plowing the potato field of his parents farm. Watch this one hour documentary about a quiet man who battled the corporate giants of Wall Street New York and won, yet few people today know who he was. Philo Farnsworth invented electronic television, yet the history books have us believing RCA was the inventor or co-inventor. Part one: Part two:
SONY IN TROUBLE?
Unfortunately, now the powerful Sony Corporation is in decline. It is sad to see that Sony’s vision was lost after the passing of co-founder Akio Morita, and earlier this year, (February, 2014) Sony announced the end of their Vaio computers and the spinoff of their television business. Sony hired their second CEO to stop the bleeding, but it hasn’t helped. It has been my long belief that to succeed you need to stay aggressive and innovate. Maybe Sony became to big in spite of themselves. Sony did innovate in their early years. Masaru Ibuka, co-founder was an engineering genius and Akio Morita was a marketing and financial genius. They did things the “SONY WAY” and proved all the naysayers wrong. They brought us outstanding new products we could not even imagine. (Apple is doing the same thing now) The inspiring story behind the Chromatron/Trinitron and the “never give up” attitude, serves as a business model for all. Sony needs to re-examine themselves and return to their core values. I hope it’s not to late.
Will the same thing happen to Apple? Time will tell.
I would like to acknowledge and thank all the contributors to this page.
See the VINTAGE MICRO TV page for additional photos, press clippings and information on the Sony KV 7010U Chromatron.