"Sylvia Else" wrote in message
...
On 6/04/2010 1:09 AM, Geoffrey S. Mendelson wrote:
Sylvia Else wrote:
If you then negate the resulting red difference component of the second
line, and average with the red difference component of the first line,
the parts received from the blue difference component cancel out,
leaving a red different component that equals the original, multiplied
by the cosine of the phase error. The same applies to the blue
component. The result is that the hues are correct, but not as saturated
as they shoud have been.

Since PAL TV sets have a saturation (color level) control, isn't that
a "non-problem". If it matters, you just adjust it to compensate.

If it's a fixed phase error, yes. If the phase error is changing slowly
over time the the picture will have a saturation that varies over time
which would be annoying if the effect were high enough.

However, I've never noticed such an effect.

Sylvia.

I would guess that you never would see such an effect, as all of the
decoders that I can remember working on, had ACC circuits which worked very
well ...

Arfa