I have developing a line following robot. The schematic can be found in this page.

http://www.james.vroman.com/javbot1a.htm

I didn't not build the exact circuit but some parts of it i left it out. I did not include the multiplexer 74HCT138 and comparator LM311. What i did is only using a IR sensor a H-bridge and a motor.

I have tested the IR with a LED replacing the motor and it works. Whenever i replaced the motor back, it won't turn. The battery i am using is that square sized 9V battery. The MicroC i am using is 16F84A. The motor i am using is slightly larger than ordinary tamiya motor; a round shaped motor.

I even tried using a smaller motor(i think they call it micromotor and the size is smaller than ordinary tamiya motor) but the same thing turns out. I also tried using op-am 741 to amplify the output voltage but nothing happen.

I tried operating the op-am on a separate circuit using whatever kind of configurations. Without load, the amplification works perfectly but when i connected it with the motor, it screwed up. Anyone can give me ideas to deal with the problems?