These have been done and sitting for a couple weeks. Now I’m finally getting around to playing again. Wheel encoder board Two QRD1114 and a 74LS14 to square up the signal. Motor controller Built on a leftover protoboard from Gadget Gangster with an ATMega328 at 16MHz (yes, running as an Arduino) and a Pololu TB6612FNG motor driver. The two wheel encoders go to the interrupt pins. The little surface mount chip still needs its connections soldered up, it’ll be the 3....

Breadboarded wheel encoder. ATMega328 on the left, 74LS14 in the middle, QRD1114 on the right. QRD1114 on a radio shack proto board. So far it seems to work as expected. Guess it’s time to build the second one.