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Geoffrey S. Mendelson Geoffrey S. Mendelson is offline
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Default Bit of a Con Really - Follow-up ...

Arfa Daily wrote:

I don't know what 'set-ups' this TV has, in terms of brightness, contrast,
colour saturation, tint/hue, but in my experience, most LCD TVs - which is,
after all, what this is - are set correctly 'out of the box', but I accept
that this particular one that I saw might not be a good example of the
technology.


Based on the assumption that it is a PAL set probably brightness,
contrast, and maybe color saturation. Digital TV sets are not PAL per
se, but they still use the same luminance, color, sync, signals that are
used by PAL (and slightly differently by NTSC).

They are also still 25 or 30 frames per second depending upon whether or
not thay are interlaced as in 1080i or not. An interlaced frame is still
2 fields, at 50 or (almost 60Hz) combined.

The main differences between a digital TV signal and an analog one are that
since each frame is discrete, there really is no need for a syncronization
pulse to define the begining of each frame and more importantly, there is
no color subcarrier.

If you were to look at a digital TV signal decoded as if it were a
stream of pixels, you would see something that looked a lot like an
analog TV signal.

Computer displays, BTW are red-green-blue with seperate horizontal and vertical
sync, which is very different.


Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM