Repair Blog of a 1967 Sony Chromatron
 

Hi to all,

Exciting stuff!

First internal/external photos ever of a 1967 Sony Chromatron color TV.
17 photos so far. Seems to be an all-tube chassis.

The Sony 19C-100 belonging to the Japan Radio Museum has been entrusted to Japanese friend N. Tezuka to make it work again.

Follow the endeavour by reading his blog:

http://translate.google.de/translate...Fvrc-tezuka%2F

Please keep in mind that Google's Japanese to English translation is, well "creative".

Later day update from info received from Japan:

CRT diagonal is 480mm/19"
CRT type is 480AB22
2x EHT rectifiers used: 1 for HV and another 1 for MV* (6.3KV) and FV* (4.1KV).
Also thinks it's a 3 gun tube, therefore not a true Chromatron.

*MV: Medium High Voltage
*FV: Focus Voltage

The Sony Museum Chromatron TV is a 19C-70 and this one is a 19C-100, therefore a new unidentified model with a smaller screen.

Best Regards

jhalphen
Paris/France

Very interesting.

Thank you for the link.

Jerome, I DON'T know where you find all this stuff, but I'm VERY glad you do, & that you selflessly always share it w/us !

Cool! Thanks for posting!
I don't get why they would be using what looks to be a delta gun in a Chromatron design... very strange!

jr

It sure looks like a delta gun to me. A lot is lost in translation. You can see it the picture. It would be neat to find one the us a tube Sony would be cool, but it would way 5 tons and would have to use o.e.m tubes from Sony.

Even if it's not a true Chromatron, a delta-gun Sony must be quite a rarity in itself.

Holy frig, 330 watts for a 19" set? That's quite the power suck.

The convergence clover gives an indication of a delta gun, but notice the close-up of the tube face that shows the phosphor stripes.

There are two high voltage connections on the bell: take a close look at the photo that shows the rear of the tube, there is a high voltage lead on the left of the tube, and a smaller one on the right!

So much for a CRT sub for one of those.

I remember seeing a Sony color set & BIG-@zz VCR on an audio-visual type roll-around cart-The metal kind schools used, prolly 1968-'69, but the TV was NOT a Trinitron... Looked more like a Zenith or RCA table model, was about 19-23" whatever they usually were. This was at Bondurant Bros. Co. in Knoxville, they were the Sony distributors for Knoxville & environs back then. I DON'T think Sony ever re-badged somebody else's sets, at least not in the "Consumer" line, but MAYBE they did in the A/V business... Anybody got any ideers ?!?

...

Notice the neck too, looks delta to me.

Not enough socket pins for triple gun?

I the early days of B/W, R-R Sony VTR's, Sony had Motorola build a 23" B/W monitor with the input connector for their VTR.
That was in the mid-60's.
The set was badged "Sony", but it was obviously a Motorola.:scratch2:

More wires visible here, and an unusual horizontally-mounted convergence panel up top.

I just realized, this is the first color CRT I've seen with the 2nd anode connector on the side, and the first from this era I've seen that lacks an external degaussing shield.

The anode button on the right everyone is talking about does not look right to me its hard to tell but it just don't look right.

I do NOT think this is a chromatron . WHY would one need convergence for a chromatron? The whole REASON for the chromatron--is to get away from the shadow mask and convergence.....this has a cloverleaf....

I think andy nailed it in an earlier post:

In this design, 3 guns are used rather than applying 3.58 mhz high voltage to the color selection grid near the phosphor.

jr

I had a color G.E. from the early 70s with the anode button on the side like that. But yeah, I can't remember any other color tv that had that type of HV connection.

IIRC the 23EGP22 was the only American color delta gun CRT with a side HV connector.

Could they be using the clover to simply align the three beams into a horizontal line, as well as for geometry?

If it was developmental towards the Trinitron, the second high voltage point might be for the h-stat convergence electrode?

It looks so "un-Sony", but I guess that comes from having never seen a Sony set that wasn't a Trinitron, or anything Sony that was tubed.

There has been a small update to the original post at the original link (unless I missed it the first time, I was having issues getting google translate to load the entire page). It appears a lot of information and possible even a schematic for the related 19C-70 model was published in a special 1967 edition of a Japanese electronics magazine: 電波科学 1967-1

I found this link for an auction selling the magazine: http://page9.auctions.yahoo.co.jp/jp/auction/k149449266

Though getting things from Yahoo auctions Japan from outside of Japan tends to be difficult and expensive.

22EP22 has a side HV connector also.

jr

This is the config. of the 7 inch Sony Chromatron.

[IMG]http://i184.photobucket.com/albums/x...magejpg1-1.jpg[/IMG]

Hi to All,

Dr ido: my friend has purchased the schematics book for me on Yahoo! Japan.

When i receive it, i will scan the interesting pages concerning the Sony 1967 Chromatron.

In the meantime, for those having issues reaching the Blog, here is the full book page + zoomed snapshots of the CRT data contained in the book.
Please bear in mind the original entire photo is only VGA resolution 640x480 and therefore quite poor; Sorry!

Photo credits: N.Tezuka

the Blog:
http://translate.google.de/translate...Fvrc-tezuka%2F

Update: Now 26 photos.

Best Regards

jhalphen
Paris/France

Interesting!

I just started re-watching a video of the repair of a 1979 13" Zenith System 3 and noticed that its CRT has a side HV connector.

Hi to all,

Sept 3rd: Noriyoshi has resumed work on restoration of the Chromatron.

Picture is now in focus and fully covers screen.
Still some work needed on the color decoder - see photos.

http://translate.google.de/translate...Fvrc-tezuka%2F

I have acquired a 1967 Japanese book where there are the schematics of the Sony 19C-90 Chromatron, essentially the same model but in a different cabinet, this one is a floor-standing model.

See the full resolution scans on Marshall's site (Thanks! for posting them).
Scanned as 4 pages to not wreck the book.
Located approx. middle of the very long page.

http://www.visions4.net/journal/chromatron

Best Regards

jhalphen
Paris/France

This has been a very interesting thread to follow. Dr. Lawrence would be proud to see that people care about his Chromatron invention and are working to restore a set made with it some 45 years later!

I also agree very "UnSony" like design, from having looked at Trintron sets all the way form a 1972 12" monitor/receiver to a 2004 34" 16x9 HD set with HDMI.

Now if we could ever find out about those TV's used by PYE for the experimental broadcast of the Coronation back in 1953. there where broad hints that those sets used where of a Chromatron design and has a 21" screen.

Matt

Hi to all,

@Matt, Thanks! and it's not quite finished yet.

For the lazy guys among us who don't have time to roam around the full size scans on Etype2's site with a magnifying glass, here are zoomed illustrations of Sony's 19C-90 in the Japanese 1967 Color TV book.

The Chromatron Noriyoshi is repairing 19C-100 has virtually the same circuitry, but in a tabletop cabinet.

The Chromatron displayed at the Sony Museum in Tokyo is referenced 19C-70 but the schematics book shows model 19C-90.
Their appearance seems totally identical. Anyway, all used the 480AB22 48cm screen diagonal Chromatron CRT.

It is interesting to observe how fast Sony progressed after the three first models (1964-1967) as the all-transistorized* KV-7010U Chromatron with an 8" screen came out in early 1968.

*except for two EHT rectifier tubes.

see E-type2's site: http://www.visions4.net/journal/chromatron

Best Regards

jhalphen
Paris/France

Thanks for sharing this with all of us Jerome.

Remember, the original Lawrence Tube renamed Chromatron was developed as BOTH one and three gun CRT's by Chromatic Television Labratory Inc. starting in 1951. Dr. Lawrence partnered with Paramount Pictures and Chromatic was a division of Paramount. Chromatic always knew that a three gun Chromatron would be considerably brighter then a one gun, but the one gun version received all the interest because of the potential simplicity of operation and lower manufacturing costs. Prototypes of both one and three gun versions were made through the years, then Sony bought the license and development rights from Paramount, first in 1961 and 1964.

Nothing against this highly informative and interesting thread, but frankly I'm surprised that it hasn't been moved to the rectangular forum. Again very interesting.

Seems like it fits here ok:

"Early Color Television (7 Viewing)
Discussions of experimental color televisions, and round screen production models, ending around 1966."

jr

I have a Setchell Carlson tube color monitor with Sony badging. http://videokarma.org/showthread.php...tchell+Carlson It probably was made as an accessory or a trade show monitor for some early tape or camera gear.

The Sony Profeel system circa 1980’s

https://visions4netjournal.com/wp-co...491E949A2.jpeg

That clunking SL-5000 Betamax came out in 1981.. Those have a handful of defected electrolytic caps on the servo board which cause unstable playback between the drum speed and tape speeds..

We had a profeel customer with a large monitor that we kept taking back to the shop for a shutting itself off symptom. I forget the size of the set but I want to say at least a 21 inch or larger. That was a heavy monitor. I think we had it back and forth between the owners home and the shop at least 3 times. Even put heavy blanket to try to get it to heat up. We finally did get it fixed. It was the HV shutdown circuitry that was detecting arcing in the HV block. A new HV block fixed it finally.