Servo help with Netduino - weird behavior, burned out board

Hi! I'm very much a newbie at Netduino (used to working with an Arduino) and could very much use some help on a project I'm working on. I hooked up a GWS S125 1T 2BB servo to my Netduino, and - using Chris Seto's assembly and code - was able to get the servo to turn. However, it never worked quite right - first, it dimmed the LEDs on the Netduino when the servo turned. Secondly, the servo seemed to turn to random positions - never consistent. Finally, after testing with this for awhile, my Netduino Plus died forever. The specs on the servo say that it requires 4.8v, so I'm not sure why it did this. Does anyone know what I did wrong? Do I need an interim circuit between the servo and the Netduino? I'd really like to figure out what the problem was before blowing another $70 board Thanks! -T

Hi Tarkon, How did you power the servos? The PWM output from the Netduino can generate the signals needed to power the servos--but you'll need to use an H-Bridge powered by the 5V header to actually power the servos. And for higher-power servos, you'll want to provide an external power source to the H-Bridges. Also--it sounds like the Netduino Plus has been damaged, but I would still try to erase and reflash the unit. There's a small chance you can bring it back from the dead If you have a diagram (Fritzing?) of how you're hooking things up perhaps some of us can pitch in with some best-practices recommendations? Chris

I've got away with some small servos with very little load working when powered by the 5V out on a Netduino Mini. Not sure it's ideal, especially for a motor under any strain. Powering them independently of the Netduino would be much better.

I also found that even these needed a decent battery. It wouldn't take too much to pull the battery output voltage down low enough that the Netduino Vin was too low and my code crashed.

The ideal setup - a decent 9v power supply and a separate 5V regulator (or whatever the servos need) providing power to the servos.