Hello,
I have an Apple II+ with Video sync issues,
Using a standard Apple composite monitor, I had vertical sync issues, and I changed a few ICs to fix it : 74LS161 x2 at D11 and D12, 74LS32 at C13 and 74LS32 at C14.
Now the image is stable with the classic monitor.
However when I use a Retrotink 2x pro, I do not get any sync (black screen). Using another Apple IIe I succeed with the retrotink.
Is there any good document explaining step by step to troubleshoot the apple II video sygnal using an Oscilloscope?
Where to start with ?
Thanks
Vincent
I've run into several NTSC -> HDMI converters which work fine with a //e or IIgs but produce very poor results or no picture at all from a ][+ or clone and ever more that won't sync right to a Videx type 80 column card even though they work fine with 80 column output from a //e or IIgs.
Apple did some things with the //e which improved its compatibility with a lot of NTSC devices which I'm not sure can easily be retrofitted to a ][+.
Interested to hear what you find. My XRGB2+ Scaler has issues with IIe composite only in monochrome text, graphics work. I never went as far as trying to clean up the signal in the Apple IIs, it's really the same with this scaler across all my IIe and II+ systems as far as I remember.
Ok thanks for the feedback,
I will stop to fight to get this ‹orking ;)
Vincent
You might consider an A2VGA card or try a diferent NTSC->HDMI adapter. As I said, I've had different results with different ones.