>And you can do an Apple-like chroma phase shift to make colors. You
>have to make the chroma burst appear during the "front porch" of the
>H lines, though.
>
>As I recall (this is entirely from Woz's description to me ca. 1975;
>sorry if I'm fuzzy on the details) they used the chroma clock and
>phase shifted it (whether using delays through gates/RC or a divider
>or something, I don't recall).
>
>They then used a gate or analog switch to route the proper phase (i.e.
>color) chroma signal out to the video.

Yeah, the company I worked for in NZ in the early 80's had the agency for
the OSI range of computers, and we did a similar thing to allow connection
to a PAL colour set. a 74L04 gate package gave just the right phase shift at
4.43 MHz to allow the different phases we required. We had quite a bit of
difficulty getting the required chips, as the 74LS range was well under way
to taking over from the 74L range even then.

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