PAL vs. NTSC on A1200

[orb85750]

OK, I know that OS3.0/3.1 can switch between PAL and NTSC at boot-up.  But is it simply the kickstart ROM that determines which way it boots by default?  Or is there any other hardware/software side to it?  In other words, can I make a machine NTSC by exchanging the kickstart with an NTSC ROM?

[orb85750]

OK, thanks for the info.  If the motherboards are physically different (and I do believe all of you!), then why is one able to boot the NTSC machine in either mode and a PAL machine in either mode too?  It must be some type of software trick fix?

[orb85750]

To make the A1200 NTSC you need to connect pin 41 of the Alice custom chip to ground, and that causes the A1200 to default to NTSC. If you are going to use the rf or composite outputs, you will need to change the built-in modulator, as NTSC signals have a different colour encoding system than PAL.
If you will only use the RGB port just do the pin ground mod and you will be set. Anyway, instead of changing the built-in modulator you can also attach an NTSC A520 external modulator.

I hope it helps.

Yes, quite helpful.  Thanks.  Any suggested ground?