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I was looking to test some upcoming game releases from The Future Was 8 bit, and I had a title for the Commodore 16 / plus 4. I like to test these on PAL and NTSC machines to make sure there are no issues. In the past I had converted a Commodore 16, but I couldn't locate it, so I converted another one.
converting a PAL VIC20 into NTSC. This required a change of a crystal, a ROM, the VIC chip and a few miscellaneous parts.
DIAG264 cartridge from TFW8b.
Diag264 by Rob Clarke. Time to give NTSC a go.