telljcl

I had a need (not RC) of using an old servo to turn a knob proportionally to a 0-5v voltage. Could I use a servo tester or some other reasonably inexpensive device to accomplish this?

In other words, at 0v the servo arm is in the neutral position (or negative rotation limit maybe), and at 5v it is rotated to the limit in the other direction.

Like turning the knob on a tester, or moving the stick on a transmitter, only modulated by the voltage.

Thanks for any DIY ideas on a simple solution!

A. J. Clark

You can use a servo tester to rotate the servo but it doesn't work exactly like your thinking. You need a power supply. 5v would do it for most servos. Plus you need a signal that can be pulse width modulated with the right pulse width that can also be veried to put on the signal wire. Check this site out it explains how servos work. https://www.servocity.com/servo-faqs/

telljcl

Thanks for the reply. I guess I was thinking of some simple circuit that would mimic x-mitter control stick input using 0-5vdc.

I could probably kludge together something using a servo tester etc... though I guess.

Thanks again for the input!

AndreyT

You need to convert a 0-5V analog signal into the corresponding pulse-encoded (pseudo-PWM) signal signal for the servo. Barring a pre-made device designed to do exactly that, I'd say that in this day and age one of the simplest immediate solutions would be an Arduino board, which can be made to do that with a very simple program. Of course, if you are familiar with [Arduino] programming that is...