Easier Approach to Electronic Projects

Servo Tester using 555 Timer

This circuit is a servo tester, probably when you purchase a servo for your robot or model the first thing is you want to test whether it works or not. There are already commercial small circuits available for this in which is like a small box where you put in battery and hook your servo to the right terminals and it plays your servo.

I searched over internet and tried finding one where we can test it for both directions, Clock-wise and anti Clock-Wise. and this is the circuit I got. This is what the simplest testing servo circuit using 555 timer I found. Made some variations in original Circuit. 

Check this other circuit which controls the speed of the servo using 555 timer and potentiometer http://rookieelectronics.com/servo-speed-tester/


Parts List:

  1. 68K, 47K, 33K, 10K, 1K
  2. 100nF
  3. BC547 Transistor
  4. 2 Push Switches(optional)
  5. 555 Timer IC
  6. Contineous Rotation Servo   



Circuit Diagram:










BreadBoard Arrangement:


Servo Used in this Project:

The servo used in the above project is by Parallax and following are it’s Specifications:

  • Power: 4.8 – 6 V
  • Top 4.8 V speed: 60 RPM (with no load)
  • Torque: 2.4 kg-cm/33.3 oz-in at 4.8 V, 3.0 kg-cm
  • Weight: 43 g/1.5 oz with servo horn and screw
  • Size (L x W x H): 40.5 mm x 20.0 mm x 38.0 mm
  • Control interface: Pulse width control, 1.50 ms 
  • Manual adjustment port
   Order it Online