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Thinking of ways to run 2 continuous servos.

2 questions that should tell me wether this is possible or not.

 

1.  Is it possible to connect 2 servos to the same potentiometer?  

2.  Is it possible to connect the signal lines of 2 servos to the same servo pin on a PICAXE?  Or would this overload the         poor little chip?

 

I know you're going to ask so here's the reason.  For question 1 I'm trying to eliminate the difference in the pulse length to obtain 0 (motors stop) between 2 servos.  I am assuming that most of the time it's due to variances between the pots or resistors used on each servo.  For question 2, I'm thinking about running 2 servos in unison at the same speed where only one pin is available on the MicroController.

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1) There is no gaurantee that both servos will stop at the same potentiometer setting.

2) The same pulse width will not necessarily obtain the same speed, especially when you start loading the servo.

1) Since the potentiometer is simply providing a voltage, you should be able to, although I have never tried it. This will only work if both servos have the same ground and power connection.

2) You can drive two servos from the same signal. Usually there is a resistor ( I use 220 ohm ) in series with the signal. If you do this, I would put a seperate resistor to each sevo, maybe a 470 ohm or even 1K. Again, both servos need to have the same ground connection.

I checked the servo specs at http://www.hitecrcd.com/product_file/file/23/Servomanual.pdf, but they don't specify an input impedence or drive signal current, so it may be worth measuring one servo and see what the current is.