SERVO TESTER Circuit
This circuit can be used to
manually turn a servo clockwise and anti-clockwise. By pushing
the forward or reverse button for a short period of time you can
control the rotation of the servo. It will also test a servo.
Here is a photo of a kit from
Cana Kit for $10.00 plus
postage (it is a slightly different circuit) and a motor and
gearbox, commonly called a "servo." The output shaft has a disk or
wheel containing holes. A linkage or push-rod is fitted to a hole
and when the disk rotates, the shaft is pushed and pulled. The shaft
only rotates about 180° to actuate flaps or ailerons etc.
A pot can be used to control the position of the servo by using the
following circuit. It produces a positive pulse
between about 0.9 milliseconds and 2.1 milliseconds. The off period
between pulses is about 40 milliseconds. This can be shortened by
reducing the value of the 3M3 resistor.