Star Tech Journal

Taito US Classic Encoder Mod
Phil Ivany
Regent Vending & Amusement Ltd.
Ottawa, Ontario, Canada
PROBLEM
Cannot obtain maximum swing from the track
ball. The etched encoder wheel wasn't centered
properly with the optical coupler thereby caus-
ing it to rub against the optical coupler, slowing
the speed down.
SOLUTION
Grind the upper and lower housing of the track
ball assembly. At the point where the housing
touches Pin 14 ofIC 74HC14 grind ata 45 degree
angle. This relieved the pressure of th_e encoder
board. This helped the distance a great deal.
NOTE
By grinding the housing, it takes the pressure off
the encoder board. Adding a small washer be-
hind the etched encoder wheel will help the
spacing as well. Adding a washer that is too big,
however, will impede the encoder wheel.