Thread: Servo question
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Unread 22-01-2013, 21:17
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Re: Servo question

I think I see the confusion. I'm afraid servos are a bit more complex than that - they depend on seeing a pulse-width modulated (PWM) input as sort of a heartbeat, so they can tell the difference between being given a signal and being unplugged (it's a safety thing, and it's good, trust me). A typical hobby servo PWM signal pulses at 50 Hz and has a pulse width of between 1 mS and 2 mS - the wider the pulse width, the greater the angle (with 1.5 mS being neutral). Unfortunately, no servo I know of will respond in any way to a constantly-high or constantly-low signal - they specifically require that they be pulsed at 50 Hz (though that spec can be a little loose) with a pulse width between 1 mS and 2 mS. If you want dead-simple low-power full-CW or full-CCW and don't have the patience to do hobby servos, you might try wiring to a motor directly to a double-pole double-throw switch that either makes the motor rotate CW or CCW, and use limit switches to break connection when you get to your desired angle.

Luck,

Sparks
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Last edited by Sparks333 : 22-01-2013 at 21:31.