Scandoubler schematics

[countzero]

If you want to plug in to the rgb port, you have to perform three tasks :

1 - decode the analogue RGB signal to digital (ADC)
2 - double the frequency
3 - convert the digital signal to analogue (DAC)

but, you can skip the first step if you use the digital signals directly from the amiga. For big box amigas, these are provided on the video slot. For desktop amigas you need some adaptors clipping on chips (well denise or lisa).

I asked this question before in another forum and got some valuable answers. You might want to check that.

[countzero]

well, it shouldn't be too difficult if there were chips which handled the scandoubling. The averlogic chip seems good, but it says RGB 565 which sounds inadequate for AGA screenmodes. Though there are 8 bit DACs in the spreadsheet so I'm not sure if it actually performs real 8 bit scandoubling.

[countzero]

yes, there are. the Xrgb and the CM-345S are the first to spring to mind. They equally (or more) expensive as the scandoublers.

[countzero]

alexh wrote:

You could make a 16-bit scandoubler/flicker fixer for video slots for well under €20 each, but who wants that?

maybe ECS users ? an internal scandoubler for the A500/A600 would need only 12 bits right ?