When I worked for a video company in the '60's, we had a variation on
the NTSC phrase: "Never Twice the Same Color" since, unlike many
European systems, we have knobs on our equipment that allow us to make
the video picture look any way we want. Unfortunately, there is no
"standard" way for most people to set up their picture monitors unless
they use professional vector scopes with a system generated (as in a
professional video facility) color bars test signal. I've seen some
pretty strange results when people use their naked eyes at home.
Also, the video house's accompanying audio test tone is generally at
1000 Hz (cycles) which is used to set a zero level on a VU meter or
digital level indicator on the recorder for the maximum record input
level, so that one does not put too high a sound level through the
machine which would result in distortion (over modulation). Generally,
the meter will have a red area above the zero level that represents that
aural boundary, and one tries to avoid "peaking" past the zero "into the
red".
I hope this adds a little more insight to the subject.
Rod
Family Theater Productions
Alex Hartov wrote:
> On Wednesday, Oct 22, 2003, at 15:24 US/Eastern, Tony Greiner/Mary
> Grant wrote:
>
>> What does NTSC stand for, and where can people get a color bar?
>>
>
> Sorry folks, I could not resist the temptation. I used to work in TV
> testing & we used to say that NTSC stands for "Never the same color"
>
> As for where you can get a test pattern, several test instrument maker
> make dedicated test pattern generators for TV. Some general purpose
> waveform generators also have the capability to produce TV test
> patterns. Here are some examples, you can find many more on the web:
> AMT CB203A Colour Bar Genenrator from Abletron,
> http://www.abletron.com/TV%20&%20Video%20Tester.htm, other choices:
> http://www.albanelectronics.co.uk/p_audio.htm.
>
> Much cheaper, if you have a computer with a composite video or SVHS
> output (some laptops do), you may be able to create your own pattern of
> vertical bars using any program you like and use that as a test for
> your TV.
>
>
> alex
>
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