What do a mouse and a trackball have in common? Everything! The guts of a standard mechanical mouse are virtually identical to the inner workings of an arcade trackball. As a result, hacking a mouse circuit board and rewiring an arcade trackball are relatively simple procedures. Everything except that last sentance was true.

In my planning of the arcade control panel I needed to look at the available arcade trackballs online. A standard three inch trackball of original arcade quality costs about a hundred twenty dollars. Since I am designing this first rig on a budget, the idea of refurbishing one of the existing arcade trackballs that I removed from the unit was a very attractive prospect. Time to bust out the old screwdriver.



Twenty two years has not been kind to this trackball. The accumulated pizza grease from two decades of use by idiotic teenagers has transformed the eggshell colored trackball into something more resembling a dinosaur egg. Oxidization from being stored in a tent has cause the axles inside to rust. Before I could get this thing rewired again, I had to scrape out the hair, goo, filth, dirt and rust and polish that ball up to a mirror shine.

First thing I did was head to CVS to pick up cleaning agents for the ball. I devised a three step cleaning process that started with soaking the ball in 91% isopropyl alcohol. This step is to remove built up grime so the additional cleaning agents can get at the surface of the trackball. Next step was to soak the ball overnight with Polident denture whitening tabs. The tablets remove any build up that the alcohol missed and break away thin layers of filth on the surface. Lastly, the balls were soaked in bleach overnight to color any remaining residue white. I rubbed the axles down with alcohol to remove the rust and sprayed the bearings with WD-40 to restore their spin.



The next step was to dismantle the mouse that I was going to hack and remove the internal circuit board. As I mentioned in the beginning, both the trackball and a mouse have a lot in common. Both have internal ball bearings that move axles with an encoder wheel at the end sporting teeth around the perimeter. Two sets of infrared LED emitters and sensors determine movement data by analyzing how many times the infrared connection is broken by the spinning teeth. By removing the X and Y Axis Emitters and Receivers from the mouse circuit board, the wires from the X and Y Emitters and Receivers on the trackball can be wired into the empty board holes. Now the mouse circuit board will relay the trackball data to the computer via the mouse port.



I warmed up my soldering iron and proceded to remove the receivers from the mouse circuit board. Because the receivers require power to interpret the infrared signal, one of the circuit traces for each of the receivers is devoted to the electrical charge. Before I could proceed to solder the trackball wires onto the board, I had to use a manual ranging multimeter to determine which combination of solder points yielded a five volt charge. With the circuit traces determined we can now start the insanity.