Big Book of Amiga Hardware

A basic scandoubler which takes a 15Khz PAL or NTSC screen and scandoubles it for use on an SVGA monitor via the use of a standard 15pin VGA connector. There are two sets of jumpers on the card. J2 enables the mode promoting of the Super72 800x600 screenmode, with the drawback that every second row is not displayed. It also requires a monitor which is capable of displaying a Horizontal frequency of approximately 48Khz. The other Jumper J1 is used for setting the correct display timing for both NTSC and PAL screens. For an A4000 the correct timing seems to be pins 2 + 3 being shorted on J1. Other Amiga models may require experimentation.