GM-20 Driver (Discontinued)
The GM-20 Driver was created to greatly simplify adding a mechanical shutter to your laser projector. The GM-20, manufactured by General Scanning, is a very quiet mechanical shutter that uses a torsion bar to return the actuator shaft to a home position when no current flows thru the coils. A relatively large amount of current is required to move the shaft of the GM-20 which is why a driver circuit is needed. Simply attaching a GM-20 to ILDA pin 13 usually isn't sufficient to run the GM-20. With this GM-20 Driver simply apply +5V (you can supply up to +9V) to the driver and connect the "Mod" screw terminal to ILDA pin 13 and that's it! The driver circuit provides damping to reduce bounce and is back EMF protected. Mod input takes around 100uA to trigger.

With the new shutter options on the market, such as Pangolin's VRAD, and the limited number of surplus GM-20's available I decided to discontinue this product.