Tuning my Scanners!!

[Things]

Well, I did have a thread with this in it, in the section below, but it moved away from the sound card, and more to tuning, so I thought i'd put it in its rightful section!

OK, well, here is where I am at. If I get the ILDA test pattern looking good, the media test goes off slightly. So I tune the media test pattern till it is good, then switch back to ILDA. THen the ILDA pattern is outof whack again. I get the media test pattern good, and I get serious overshoot on the square. Any tips on how to stop it doing that??

Anyway, here are some pics:

Blanking working, "YOM". Anyone know wether the missing spots at the bottom are due to tuning or blanking? I am thinking blanking ...



"DISK" logo displaying fine, but the blank area on the d?



Perfect media test pattern (But also has the little blank spot)



the ILDA test pattern, with those same settings as above (Whats going on down in the left bottom corner tho?)



Square with those same settings (If I try remove the overshoot, it screws up other stuff )



All were at the same scan speed of about 17 - 22K

Any idea's?

What about the blanking? How do I fix that?

Cheers

[buffo]

The blanking problems are caused by your color timing being off. Normally there is a setting for "color speed" that controls the offset between the X and Y coordinate data and the color (or modulation) data for a given point. In your case, you need to increase the color offset a little bit. (That's what those horizontal lines at the top of the ILDA test pattern are for You want the short vertical lines to bisect the split or gap between the horizontal lines.)

This is a software setting that you'll need to adjust. Not sure where it is in either Spaghetti or Laserboy, so you'll need to consult with someone else for advice on how to change it. Sorry.

From the diagonal line at the bottom of the ILDA pattern and the overshoots on the center square, it's obvious you need more LF damping on both amps. But before you go too much further, see my reply in the other thread about scan angles first. You need to be sure you're not scanning the ILDA test pattern too wide when you tune. (You could be overdriving the scanners already.)

Adam

[carmangary]

Spaghetti doesn't have a color offset feature. I'll have to think about implementing that since it seems like a good idea.

I do have blanking optimization, which will also fix the problem in a different way. It works pretty well in most cases.