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Television Standards Converters, Modulators etc Standards converters, modulators anything else for providing signals to vintage televisions.

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Old 15th Sep 2011, 3:13 pm   #1
Brigham
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Default Comp. video out.

What exactly do we get from the 'composite video out' socket (the yellow one) when playing a Region 1 DVD on a British spec. multi-region player?
It certainly isn't 625/50 interlaced, yet it works on a 'normal' TV.
It plays havoc with a Domino.
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Old 15th Sep 2011, 3:19 pm   #2
ppppenguin
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Default Re: Comp. video out.

Probably PAL60. 525 line 60Hz scanning structure but with PAL 4.43MHz colour. SInce it's basically a 525/60 signal the Domino won't like it. I don't know if some DVD players do a standards conversion to 625/50. The expensive Aurora "World Converter" will handle almost any input but it's hardly a good investment for this application.
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Old 15th Sep 2011, 7:57 pm   #3
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Default Re: Comp. video out.

You'll find it only works on a normal tv because modern tvs are capable of syncing to the foreign frequency. Older TV's that play only good ol' PAL 625/50 are hit and miss.

My old SVHS vcr said it could play NTSC 525/60 recordings and it used to show 'NTSC>PAL' in the display whenever I inserted one; however it did as Jeffery says and simply converted the colour from NTSC to PAL, leaving the line scanning as per NTSC.
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Old 16th Sep 2011, 11:14 am   #4
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Default Re: Comp. video out.

No single Aurora does 525/60 to 625/50. Presumably British 405 enthusiasts in North America buy the universal converter. If we ever get $2(US) to the pound, I'll give it serious thought.

Will a vintage US set work from this output? No converter required?
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Old 16th Sep 2011, 12:07 pm   #5
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Default Re: Comp. video out.

Hi.
The original multistandard Aurora will do 525/60 to 625/50 etc, only problem when doing the field conversion it is somewhat jerky.
No colour conversion as its mono, terrific converter though.
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Old 16th Sep 2011, 12:41 pm   #6
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Default Re: Comp. video out.

625 x 25 = 15,625
525 x 30 = 15,750

Most older TVs display lack of height (30/60 rather than 25/50) doesn't give the Frame coil enough time? Error is 1.2x i.e. 20%

I never saw a problem with the line rate, presumably as it's close. Error is 1.008x, i.e. less than 1%

Some DVD players will play the US DVD as 525 /50 PAL. Some will even resample the 480 lines to 576 lines. Good multistandard DVD players are a lot smarter than VHS.

Note there are TWO kinds of USA DVD.
1) Video Originated. The DVD is stored as 30fps 60Hz interlaced 480lines
2) Film Originated. The DVD is stored as 24fps 24Hz progressive 480line and many of USA players can output essentially VGA on component (720 x 480 @ 60fps progressive) as the comb artificats are less than 3:2 pull down playing 720 x 480 30fps 60Hz interlaced.

As to what a European/PAL DVD player that is "multistandard" does depends on model and menu setting. If you have a true Multistandard TV, some DVDs can play DVD back as per USA. Some can playback in 25fps 50Hz Interlace which is preferable for film content but not for video content. Unlike VHS which either plays it as is (true multistandard) or plays it 525 line 30fps 60Hz with PAL colour.

If you only play "PAL" DVDs there is no value to Progressive Playback, it's to solve a USA problem.

Explanation of the problem of USA format playback of films and why you want a smart DVD player that does 25fps if content is progressive http://www.techtir.ie/node/1001404
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Old 16th Sep 2011, 12:49 pm   #7
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Default Re: Comp. video out.

Quote:
Originally Posted by Brigham View Post
Will a vintage US set work from this output? No converter required?
A mono set will work from it fine (since it's a 525 line, 30 fps signal); but not a colour one, unless it either can handle PAL, or is not too vintage to sport a SCART socket with RGB inputs.
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Old 16th Sep 2011, 5:58 pm   #8
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Default Re: Comp. video out.

Looks like I'll have to find a 525-line set next. Anyone know where to get an Electrohome, or a Rogers Majestic?
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Old 29th Sep 2011, 5:41 pm   #9
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Default Re: Comp. video out.

Sudden thought. Will a vintage British set work directly from this output; with a Band I modulator but no converter?
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Old 29th Sep 2011, 5:58 pm   #10
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Default Re: Comp. video out.

No. Line scan frequency is 15734Hz for NTSC, 10125Hz for 405.
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Old 29th Sep 2011, 6:09 pm   #11
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Default Re: Comp. video out.

Quote:
Originally Posted by neon indicator View Post
Most older TVs display lack of height (30/60 rather than 25/50) doesn't give the Frame coil enough time?
No, it has nothing to do with the scan coils! What happens is that the field scan is initiated by a field sync pulse, so the scan starts at the top of the field and progresses down the picture, in PAL (625/50) the next field sync pulse occurs 20mS later but in NTSC (525/60) it occurs earlier, at 16.6mS, so the field flyback also occurs earlier than with PAL, thereby reducing the picture height to 16.6mS/20mS = 83%!

Regards,

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Old 29th Sep 2011, 10:28 pm   #12
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Default Re: Comp. video out.

Basically, NI, if the field sync pulses are not generated at the same rate to which the TV has been designed/programmed, as Amrad said, it will reduce the frame height to just over 4/5ths of what it should be if it were on a 625 timebase.
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