scanners lifted ground and picture got twice as big on scanpro20s anyone know why?

[tommylee333]

i am building a red and green laser.
and on my scanpro20s you have a s+ a s- and a ground wire that comes from your dmx board to your scanners.
and so i was playing aroud with it and accidentlly disconected the ground wire from the dmx board to the scanners.
i was a distance of about 10 fsst from the wall.
and the picture projected on the wall went from about one foot tall, to abot 4 foot tall.
and from about 2 foot wide to about 7 foot wide.
does anyone here have any idea why this happened, and can i use it this way?
what size should you picture you project onto the wall from about 10 foot normally be?
the scanners run a little hotter when you disconnect the ground and the picture becomes so much bigger, but i added a fan from a computer and they colled down.
anyone here familular with scanners?
thanks and God bless.

 

[KGB_Productions]

Use this chart to find out your scan angle. If you are scanning @ or around 15 degrees @ 20k then you should be ok, but it sounds like you are scanning way above that, and that is the best way to kill your scanners, Especially cheaper ones like SP20.. If you want to scan at larger angle then you MUST turn your scan rate down to something like 10-15k, then you can scan up to 40 degrees before you blow up your scanners.

http://www.stanwax.plus.com/lw/scananglechart.pdf




-Brooks

 

[tommylee333]

how do i use the chart?
this is the first laser i have ever tried to build.

 

[tommylee333]

how do you turn your scanners down to 10 or 15k?
i just got them used off of ebay with no instructions.
pot one on the scanner board say, position scale, image size adjustmen, and input gain.
is this the one i use to adjust it with?
i don't have ilda yet i just have dmx but one of the scenes is a square so i guess i can use that to adjust it with.
but when will i know if it is at 10 or 15k?
thanks for any help and may God bless you.