My projects have been stuck for two weeks while I have read up on decoupling, shopped for components, scanned through my code, rebuilt my circuits, twisted all my wires together etc etc etc all in the hope of tracking down and eliminating a problem I have with noise when my Arduino is connected to the ESC (Electronic Speed Controller).
The problem only occurs when the Arduino is PWMing (Pulse Width Modulation) the ESC, I can PWM a servo in place of the ESC and all is fine, but as soon as I try to drive the ESC with PWM I start getting a garbage pulse every 6th pulse or so.
Now that my board is loaded up with decoupling capacitors, the problem is finally solved - with a resistor.
330 Ohm Resistor Show a resistor of 560 Ohms is being used in the project at present. The resistor is connected between the PWM Pin and the signal pin of the ESC.
I had a nagging idea that I might be damaging the PWM Pin by pulling too much current from it into the ESC so I added a 560 Ohm current limiting resistor and my rogue pulse vanished, not what I was expecting to happen but a very welcome development.
Thanks to this gentleman for the idea - http://www.thebox.myzen.co.uk/Site/Welcome.html look for the 'school box', all good stuff which has helped.
I got the idea for the resistor from reading the section about LED current draw slowly damaging pins even if it looks as if its working. It looks as if the ESC was was drawing too much current.