I recall seeing the mac video being designated a "composite" signal. Composite or NTSC is what's fed into a video monitor (not TV, unless it accepts composite input). Composite imposed on a carrier signal is what's displayed on channel 3 or 4. Composite just means everything is combined into 1 signal (video and syncs) and fed on 1 wire. Some monitors have composite sync (horizontal + vertical). Sync on green monitors have the composite sync signal fed into the green input. If you had a monitor that need a SOG signal, you can add the vertical and horizontal syncs to the green line w/a resistor. I've done it. But the Mac's composite signal is likely a different animal as Doug pointed out. It might help to scope out the point at which the video signal is created, that is where the separate components of the signal are added together - to see if the Mac's composite video can be altered to conform to the NTSC standard. This might be harder on a Mac then say an old IBM PC, being first of all there is no crt controller in a Mac. All the video is created by firmware programming of the 68k plus presumably any glue contained in custom logic chips (glue usually designates ancillary logic gates/chips like 74ls*** that you'll see all over most motherboards, and occasionally are implemented in custom chips. 1 custom chip (fpga,gal,pal,...) can do the work of dozens of discrete logic chips. This glue is needed to provide additional logic that the microprocessor or crt controller, both being general purpose ic's in some sense, don't provide, so you can customize a piece of microprocessor based logic to your specific needs. CRT controllers are also microprocessors in a broad sense, having internal registers and clocks and whatnot. Video cards these days have enormous horsepower, and are utilized by hackers to perform brute force repetitive tasks like password guessing. The firware/flashware is reworked to make the crt controller logic act like a standard micro. Wicked). This would be a terribly interesting project, and a very educational one, assuming someone was willing to get way down and dirty. If someone were able to isolate the components of the video signal (i.e determine at what point they were spit out out of some pin or whatever) I'm thinking some semi-special purpose ic could be used to morph these *bare* components into a true composite signal. Maybe I'm just nuts though.
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