View Full Version : Early color television in 1967: Is it PAL or NTSC?


yagosaga
06-29-2005, 10:18 AM
Here is an article from a German lifetime journal ("hobby") with the first public reactions to the introduction of color tv in 1967. It deals with PAL sets but if one didn't know that it is reporting PAL color tv system one may argue that it deals with NTSC:

How good are our color tv sets? "hobby" tests color tv 1967

Mrs. Fendel turns the control knobs of her new color television set - with the success that the screen remains without any picture for the rest of the evening. Mrs. Fendel does not know how to operate the push buttons and knobs. On the next day, when she called the tv serviceman, the knobs and buttons were set into the correct positions.
Certainly, the German "Bild" newspaper wrote with respect to the color television premiere on August, 25th: "It is wonderful to watch tv in different colors!" However, for some tv watchers the screen was overloaded with colors. Apart from high price the critics complain
- about the complicated operation which is not already simple by the black-and-white devices. Now with the color still two controls* were added which confuse technically untalented peoples too,
- the blurred reproduction of color broadcasts with the black-and-white tv receiver;
- the color tint in displaying black-and-white broadcasts with the color tv receiver;
- the colors of color broadcasts are not naturally and they are too strong.
A public opinion poll of the Wickert institutes in Tuebingen proved that almost one quarter of all color television sets owners are dissatisfied. "hobby" wanted to know what color television is really like. They went to two big tv dealers in Stuttgart - "Radio Stiefelmeier" and "Radio Gruener" - for a demonstration of twelve color television sets. The first impression was - very strong colors! It is alright: televised colors often look exaggerated and unnatural.
Beside this, we had to state a color tint on almost every color tv set of our examination black-and-white broadcasts. Fundamentally we came to the result that all technical presuppositions - the set, location, setting, antenna, room lighting - have to be completely OK to be able to get an optimal color picture on the screen. Therefore, the set must be put in the house of the buyer and adjust by the service man.

* The first PAL color tv sets had a color control and a tint control. The tint control regulated the white level by changing blue and red-green drive control.

avalon1308
06-29-2005, 12:50 PM
For sure, the article is talking about pal system, Germany or Europe never used the NTSC system except maybe for a few american channels (AFN Network). Late 60's, beginning of 70's, Europe countries were using various PAL and SECAM systems.
Only the real first color sets had a TINT control not to be confused with the american HUE control. The error in phase of the chroma signal did not change the color since it was constantly corrected by the "alternated line". Some sets had an automatic switching between B/W and colorcast that changed also the grid bias in order to have more natural colors (!!) (replacing the tint control). Back then even with the PAL system, colors were everything but natural.

Telecolor 3007
06-29-2005, 03:25 PM
Grate Britan made some experimetal N.T.S.C. color broadcasting starting 1955. But it introduce P.A.L. in 1967.

yagosaga
06-29-2005, 03:36 PM
Only the real first color sets had a TINT control not to be confused with the american HUE control.
I know one PAL color tv set which had really an American like hue control. It was the Porta-Color, made by Kuba Imperial. This set had no PAL delay line, it was a "Simple-PAL" receiver, and the hue control was located on the back side of the set. With this control one could shift the color demodulator axis.
I have posted this old article because it shows that reliable and natural colors didn't depend on the color tv system but on good development of the technical and electronical design of the sets.
The tv sets of the first and of the second generation had this tint control. Since 1970 the tv sets only had the color control.

David Roper
06-29-2005, 10:58 PM
Grate Britan made some experimetal N.T.S.C. color broadcasting starting 1955. But it introduce P.A.L. in 1967.
W-e-l-l, not exactly. The 1955 British color system was 405 line to be compatible with their contemporary black & white standard.

Chad Hauris
06-30-2005, 06:54 AM
There are some American NTSC tube sets which had a front panel control for the CRT screen grids for color balance (in addition to the phase control for chroma, which is usually called "tint" or "hue".)
The control for the color temperature, controlling the CRT screens was often called color fidelity, chromatone, or chromix. You could adjust for a "sepia tone" on b/w programs by using this control, or make the picture more blue, etc. similar to what can be done on some computer monitors.

Steve McVoy
06-30-2005, 07:54 AM
Here is a 405 line British color set:

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

old_tv_nut
06-30-2005, 10:57 PM
There were some Motorola tube color sets (TS-914,918,921)that had three color controls, the third one affecting red/blue DC balance. The way it arose was that they used a single split-pentode tube (6LE8) for the color oscillator/demodulator section.

This tube was a color oscillator operating between the cathode and grid1. This constituted an "electron-coupled oscillator", meaning that the signal was coupled to the plate by the elctron flow, but the plate circuit itself was not part of the oscillator. They injection-locked this oscillator to the burst, so no phase detector was required.

The chroma signal was phase split by 90 degrees and then fed into dual screen grids, resulting in demodulated R-Y and B-Y coming off the dual plates. G-Y came off the single common screen grid! The G-Y was a bit weak for correct colors - greens tended to be desaturated and run toward brown or blue.

Since the color difference signals were DC coupled to the CRT grids, imbalance in the tube's current split would run the picture toward sepia or blue-tone shadows. The more expensive sets had the third control, which adjusted the red/blue DC balance. The really cheap sets just used fixed resistors.

They called this circuit the "SODPIL" - "self oscillating demodulating phase injection lock".

blue_lateral
07-01-2005, 01:57 AM
There are some American NTSC tube sets which had a front panel control for the CRT screen grids for color balance (in addition to the phase control for chroma, which is usually called "tint" or "hue".)
The control for the color temperature, controlling the CRT screens was often called color fidelity, chromatone, or chromix. You could adjust for a "sepia tone" on b/w programs by using this control, or make the picture more blue, etc. similar to what can be done on some computer monitos.
The first works-in-a-drawer quasars (solid state) had a control like this, too. There was a "tint" control for color temperature, and a "hue" control for chroma phase.

jc

ceebee23
07-01-2005, 02:53 AM
It would be nice to have this option in modern sets ...colour television is basically artificial anyway ...imagine a stereo system with only a volume control!

nasadowsk
07-01-2005, 11:26 AM
Woah neat, the whole color demodulator, oscilator, was in one tube?

So what, tyhere was just the chroma amps, burst amp, and killer feeding it?

domfjbrown
07-01-2005, 11:50 AM
It would be nice to have this option in modern sets ...colour television is basically artificial anyway ...imagine a stereo system with only a volume control!

NVA amps only have volume and source... My Rega Mira 2k has only one better than that - tape monitor ;)

Naim amps often only have balance and source...

old_tv_nut
07-01-2005, 02:08 PM
Yep!

The earlier TS 912 had an explicit color killer stage. It worked by sensing the oscillator grid self-bias, similar to the early cheapened RCA's. Every time I see this, it makes me wonder if the oscialltor was actually free running, or a ringing circuit that died down when the burst went away.

The later chassis (the picture I posted) has no stage called color killer. I haven't figured out if the function is included somewhere else, like the burst gate.

Part of the problem of understanding old schematics is the number of special, multiple-winding coupling transformers used. Later sets with solid state and especially ICs made it possible to get rid of transformers and reduce costs.