Why in the U.S.A. the P.A.L. system was never itroduced?
 

Why, after the introducing of the P.A.L. coulr televison system in Europe, the P.A.L. was not introduced in the U.S.A. In fact, P.A.L. is superior to N.T.S.C.
They could treyed to introduce the P.A.L. on the East-Coast states with big number of inhabitants, like New York and Pennsylvania, to see if the public like it (thay also could manufactured colour sets that could work bouth in P.A.L. and N.T.S.C).

PAL may be superior, but if my study of television and its history is correct, the NTSC system was invented first, back in around 1953. PAL didn't come around until the early 1960's, and by then, the U.S. system was already firmly in place.

Tom

Firstly the colour system NTSC was already well established in the US when the PAL system was introduced in the mid 60's,

Although the PAL system was based on the NTSC system, it was refined by 3 importent technoligies.

1. A swinging burst is used to change the phase of the R-Y signal phase plus & minus 45 degrees on every 2nd line (Alt Lines)

2. A chroma delay line is employed to avarage out any phase errors in the chroma signal.

3. A half line frequency or ident signal is used to switch the phase of the R-Y signal on every 2nd line.

To have introduce now would have made all existing colour TV's in the US obsolete.

That would probably be easy today with the whole TV system on a chip, but back in the tube days it would have cost quite a bit of $$$ to duplicate both systems in every set. Maybe PAL was better (I don't know the specifics) but I doubt it was THAT much better to justify screwing around with trying to convert from existing NTSC being adopted in the US to use PAL instead, duplicate the broadcasting equipment etc. Sounds like a potential nightmare to me.

From all I have read, PAL is/was indeed better than NTSC... they didn't jokingly call it Never Twice the Same Color for nothing.
Tom

Most of the Never The Same Color problems come from the production end not the set. The biggest difference with PAL vs NTSC is the frame rate. I can't stand the flicker myself. It may have a bit more stable color but there was no reason to change.
Just think what it would have been to move back east and your color tv won't work. We had millons of set by the time PAL came around.

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Remember Japan has 50HZ power and 60 field 30 frame NTSC just like the US does. Some poeple think PAL may look better because it has better vert resolution because of the 50 HZ frame rate.

Americans are a stuborn bunch
 

Just as with HDTV, when the Japanese thought they were a shoe-in for the system they went with 15 years ago, the atsc went thru 9 propsed systems before settling on our current form of digital television. The ntsc system was already too far down the line with color already being demonstated in the forties using the ntsc system. If I were an engineer I would be biased against something that someone else thought up. Pal and Secam are better systems but so was the beta-max vs vhs. the rest is history.

The second N.T.S.C. (the one in the early 50's that set the U.S. color system) did experiment with phase alternation, but at field rate. They wanted to try this to allow both the I and Q signals to have asymmetrical sidebands, which would cause phase distortion at the edges of objects. There were no 1-line delay lines, let alone 1-field, so those sets had to rely on eyeball averaging of the phase. (The first practical consumer-priced 1-H delay lines were the galss ultrasonic lines developoed for PAL TVs in the 60's.) They concluded that there was noticeable flicker, and the phase distortion problem was eliminated by the use of extended lower I sideband only, with symmentrical Q sidebands. They did not directly contemplate using phase alternation as a means of reducing or eliminating hue adjustment errors.

By the way I disagree that SECAM is superior to any other color system - it requires all sorts of compromises in the system design to prevent objectionable cross-luma artifacts, and is impossible to use in even simple mixing systems due to the impossibility of linearly adding the FM subcarriers from two pictures. Production for SECAM countries is typically done in PAL, with a final conversion to SECAM for broadcast. If they had kept the concept of alternatng R-Y and B-Y lines, but used AM carriers instead of FM, it would have achieved the goal of hue stabililty without all the detriments that it has. Also, because of the frequency modulation, usign a comb filter to improve luma resolution is impossible in SECAM. (Color saturation is another matter - both NTSC and PAL can suffer color saturation errors if the color subcarrier is attenuated or amplified with respect to the luma, as in antennas or ghosted channels that do not have a flat frequency response, while SECAM will maintain correct saturation regardless.).

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I assume that you would not only obsolete all of the color NTSC sets by switching to PAL, but also the black and white sets in use too. NTSC came about partly because it was backwards compatable with B&W tv.

Ive owned several tv's(during the 80's and 90's )that were PAL and NTSC together.They came in handy when I was in the military(they sold them on military bases),moving so often all over the world.I even had a few dual system VCR's.God help you if you got back to the states,and sold your tv/vcr,and still had tons of PAL tapes :thumbsdn:
Jimmy

Oh, they could have done a PAL system using 525i/60Hz scan rate. Think somewhere in South America has that. So B&W sets would still work. Existing color sets (NTSC) would get real confused on a PAL signal with a subcarrier at 3.579MHz, as the "V" or "Pb" chroma signal would be flipping polarity line to line. Reds would stay reasonably consistant, but blues would bounce between blue and yellow line to line, essebntially canceling out at distant viewing distances from the set.

The slight improvement PAL would then give wouldn't have been worth the penalty of obsoleting all teh existing color sets and studio equipment already in the field.

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