On 7.2.13 11:35 , Ian Field wrote:


"Tilmann Reh" wrote in message
...
Michael A. Terrell schrieb:

80's vintage German printing equipment (offset press industry) uses
a video
plug-in card (made by the manufacturer of this equipment) to generate
parameter display for the operator. The display is a standard
baseband video
tube monitor. (It is possible, being German and sold in the USA
market, that
the video may be NTSC or PAL.)

If it's monochrome, we don't need to talk about NTSC or PAL and their
particular color carrier frequencies...


In PAL & NTSC; the colour carrier was a multiple of the line rate.


Not quite.

In PAL, the subcarrier is 4.433618 MHz and the line rate is 15625 Hz,
the ratio is 283.75512, not an exact multiple.

When I studied the thing in the 60's, the explanation was to find
a frequency at as non-integer rate as possible, to get rid of
Moire effects.

--

Tauno Voipio