It SHOULD work with an Omni-Pac. The trackball has 2 slotted discs with and emitter and receiver U-shaped unit. As you spin the ball, it spins on rollers that spin the discs, creating spaced signals from the emitter/receiver. You should be able to hook this to your optipac, as long as you provide a power source to the emitter/receiver unit so it will work. Maybe the opti-pac provides this power source. Dunno.