But you can only give full throttle or no throttle at all, right?

No, it's all variable. How ever much you turn the knob that's how much throttle you get.

http://www.youtube.com/watch?v=GSHms...eature=related

Oh now I know where the knob is... :lol:

Still got a few questions, to make it easier, I made something in Paint. Are all these things right that I'm describing in this pic? And what are those things where ??? stands?

Pic:
http://img5.imageshack.us/img5/3453/87927111.png

I'm holding one of those in my hands right now. The wires are a 6-22v input. The 2 pin is for a 4-5.5v input. You can use either one.

With the button. There are four lights(the white things). One is power. The other displey the mode. One is normal use the knob to turn the servo (or throttle). One is make the servo go back and fourth as fast as it can to test the speed. The other is some wierd mode that is wierd. It might center the servo.... The button switches through the modes.

Oh ok, I thought the Servotester would get his power from the ESC (Like a normal receiver)

Well, thank you for your help Metal! :yes:

If the esc has a bec it might be able to get it's power from it, but most likely you'll need to hook up power to one of the two inputs from an external bec, power jacked off the esc lead (make two wires coming from the esc, one for the input and on for the bec output) or hook it up to your main batteries if you aren't running more then 22v. I'm going to hook mine up to one of my 12v lead acid batteries.