Quote Originally Posted by burak450 View Post
as you said that you mean same ground but another power supply...

did I understand right?
No I mean read back thru the thread! I don't see any mention of adding any capacitors anywhere in the circuit...except where somebody but you has mentioned them...
And, you say you are using a switching adapter, like a wall-wart rated at [email protected]?
How long is the cord feeding the PIC/servos? How much 'noise' is getting to your PIC? How much 'noise' does your servo generate under a load? Any capacitors in there anywhere?
http://en.wikipedia.org/wiki/Decoupling_capacitor