Originally Posted by
MisterWilling
Well after hooking the dac to the oscilloscope I know its the DAC and not the scanners. The scanners are displaying the exact same thing as I see on the Oscilloscope.
Now I have to figure out why the DAC is outputting this pattern, is looks like a jumble of points is just way outside the "square". If you look back a few posts, the image I projected from the scanners is the same as pictured below (except flipped in x and y)
I also downloaded the ILDA test frame "b" to see what it looked like. It is about the same but with less points.
When I scale the image down, the square is the only thing that shrinks. The distance between the square and the outside points stays the same. So the scale doesn't seem to affect the rouge points.
This is why I think it's a grounding issue. When you change the scale of the image, the only thing that should change is the X,Y galvos signal amplitude. The blanking channels will stay the same. Since you can see large parts of the test frame in the first image, parts of the image are getting to the galvos without being molested by blanking signals which is how it should be since the laser only blanks between lines. Therefore the blanking signals will skew parts of the image away from where they should be by about 5V, leaving other parts unchanged (the parts that are recognizable) when there is no activity on the blanking channels. Since both X and Y are affected because they share the same ground as the blanking channels, the image will be skewed diagonally rather than horizonally or vertically.
Any Suggestions?