Hacked HX12K servo - Erratic behavior.

Hi, I'm new to this forum and am a novice when it comes to electronics in general.

I acquired a remote controlled tank that my uncle put together using a radio receiver and 2 hacked hex Teck HX12K servos. I am trying to instead run these servos off of an arduino UNO instead on the radio receiver. The problem I am having is that the servos run erratically as soon as the myservo.attach() executes. The servos will begin to spin in one direction, hold still for a moment and spin in reverse for random duration's and in a random order.

I've tried to write to the servos using the myservo.write() command with various values and tried to use capacitors and a pot to find the null position but, alas, get the same result. there doesn't appear to be any pattern to the movements and my google search has yielded no solution.

I know the servos can work as they respond to the remote control as expected. If it is of any use, the radio receiver is a HK60F 6 channel receiver, and the servos are powered independently via a transformer connected to the mains set to 6V.

Could anyone possibly shed some light on what the issue could be? any direction would be immensely appreciated.

Many thanks.

make sure all grounds are connected together..

Thanks for the reply xl97. I have been testing only one servo at a time and it is grounded to an AC - DC transformer set at 6v. though changing the voltage does not seem to help. The issue continues at different speeds.

I'm not saying that is your only problem.. but your trying to 'change the voltage'..

your trying to make sure all grounds have the same 'playing field/know about each other' (so to speak)..

without code and pics of your set-up though...

people will just be guessing.