T500 RC Control, Servo Issue

I have just received a TIC T500 controller, which I have a small stepper motor connected to. The plan is to use it with a radio control transmitter.
I have set the motor up for control and speed, plugged it into the receiver and it works as it should when using the transmitted joystick. I have another servo plugged into the receiver, which again works fine when the T500 is connected to the computer however as soon as I disconnect the T500 from the computer the servos go crazy and the lights in the T500 start flashing.
The stepper motor however still works as it should do. As soon as I plug it back into the computer I have normal control over the servos again.
Do you have any suggestions on what the issue is and how to rectify it as I am looking to plug 3-4 servos into the receiver to work along side the T500 and stepper motor.


From your description, that sounds like it could be caused from an inadequate power supply or possibly a bad ground connection. What are you using for your power source? How much current can it handle, and how much do you expect your system to draw?

Also, could you post some pictures of your setup that show how everything is connected?