Originally Posted by
madgadget
I can see a TTL input to the lower LHS of that pcb. I assume you toggle that with 0/5v to turn the laser off/on.
He has the type of TTL that is "Pull down to blank", so he needs a real TTL signal to drive it.
Simple test, short across the red to the black on the blanking input once the laser is on with a small piece of wire, The laser should wink out. It wont hurt it to do this test. This should be a sticky, but TTL logic can both source or sink current, and you need a "sink" to blank. In this case the black wire on the blanking input goes to signal ground on the show controller and the red wire goes to the color signal. Some place around 1.6V the laser will blank, and some placed around 2.4V it will unblank (those are the standard Transistor Transistor Logic signal levels) , so you may need to invert your blanking in software.
The Chinese do it this way so they dont get dozens of lasers shipped back to them as dead.
Steve
Steve
Qui habet Christos, habet Vitam!
I should have rented the space under my name for advertising.
When I still could have...