Two servos on Uno

Using Arduino Project Guidance
1

I've been trying a project form 30 Arduino project for the evil genius. the one with the two servos and the laser. When I put servos on my board they act erratically moving in random directions constantly. So I tried loading the example from the servo library and run them one at a time and they behave. However, if I modify that code to run two servos like the original project they move erratically again. I'm using these servos Servo - Generic Metal Gear (Micro Size) - ROB-14760 - SparkFun Electronics. Is there something I'm not considering?

Thanks,
Robert

2

Are you powering the servos from the Arduino?- if so, you should provide them with their own power, and only have the control signal from the Arduino. Link the grounds together: see attached pic.

two servo.jpg
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