New to the forums and looking for some advice

[Rhett]

no luck so far figuring out the problem. I've added a 25v 1000uf electrolytic cap and a .47uf ceramic cap across the power battery leads and several different ceramic caps across the motor leads. I've tried several different small dc motors I have around and they all do the same thing. Did extensive (30 minutes) test with a relay as the load, switching polarity every second or so and couldn't get it to freeze (which leads me to believe it is interference from the motor). I also added four 10k resistors, 2 from the bases of the npn's to the ground and 2 from the bases of the pnp's to the positive.

Them problem persist though and I'm all out of ideas again.

 

[Rhett]

moving the point where the accelerometer was grounded in the circuit seems to have solved the issue.

 

[(*steve*)]

If this is the case, then your problem may have been caused by heavy currents in your ground return changing the ground potential in parts of your circuit.

This is not an uncommon problem in circuits containing motors and is why it is often suggested to run dedicated power leads to your motor and to decouple the power supply to more sensitive electronics.

If this is the case, I'm also sorry we didn't suggest it as a possibility earlier.

 

[Rhett]

no worries steve. alls well that ends well. I'm sure I'll run into more hurdles you can help me with before I'm done