PWM coming out at 5 volt, I thought but no I'm not sure. I have tried with and without the resistor getting the same results from 220 ohm to 1k. The voltage on the other side of the resitor drops to 1.3V. I will redo my circuit from scratch because I'm starting to think there is a power supply problem on the Arduino side. I'll recheck the voltages. If I don't plug in ground, the arduino gets enough ground through the pwm pin to run. I may have a fault in the wire going down. And lastly, I'm tired, my wife is tired of my mess, I've just commited to throwing it all out. Free treadmill in Steinbach!What is the voltage of your PWM signal and do you have the series resistor in circuit for the Opto input?
Thanks. Sorry. I shouldn't have bothered anybody.