Problem with continuous rotation servo. Only one direction

Using Arduino Motors, Mechanics, Power and CNC
1

Hi,
I modified my servo to to continuous rotation by this method:

But I used 2 resistors 1K each side.

To test my servo I'm using this code:
#include <Servo.h>

Servo myservo;

void setup()
{
myservo.attach(9);
}

void loop()
{
myservo.write(180);
delay(3000);
myservo.write(0);
delay(3000);
}

Servo is rotating only in one direction and it's not changing after 3 seconds.
!!It's only rotating slower!! (when myservo.write(0):wink:

Thanks for answers!
And sorry for my english. :slight_smile:

2

Are you certain you connected the resistors to the correct terminals on the servo's circuit board?

edit: One terminal should be ground, another should be 5 to 6 volts, and the third should now be 2.5 to 3 volts where both resistors are connected.

3

Here's the picture.
I did this a little different method. I thought it will work, but it doesn't.

4

I suspect you have the resistors connected wrong.

The black wire is probably ground. One resistor should connect there.

The red wire is probably 5 to 6 volts (V+). One resistor should connect there.

The orange wire is probably the sense wire. Both resistors should connect there.

Those connections must be on the circuit board inside. It looks like you are connecting the resistors to the wires from the JS connector. That won't work.

edit: Watch that video again and pay close attention to the terminals where those resistors should be connected.

5

A better way to mod that servo might be to remove the stop tab on the output shaft and drill the pot shaft hole in the output slightly larger such that the output shaft slips on the pot shaft. Calibrate the servo by sending a 1500us command to the servo and tweak the pot shaft until the motor stops. Then put a small drop of glue at the base of the pot shaft so it won't turn and lose the neutral position. Then put it all back together.
I've got a couple of the $1.99 9g servos for the main purpose of using the internal electronics to drive a 43A H-bridge.

6