Maker Tools

Digital Servo Tester Controller with Voltage Display

Cheap board gives you a quick way to play around with servos

It’s time for another Cool Tools video review! This time we’re taking a look at this Servo Tester Control board. I picked this up for $10 on Amazon.

Servos are one of the coolest weapons in the maker arsenal. Unlike a simple motor, which spins either forward or backward, a servo provides, gradual, precise movement left or right. They’re the steering mechanism in any remote controlled car you’ve ever played with.

But to make a servo work, you have to send it more than just power — you have to send it a control signal too. Otherwise, it won’t move at all.

Now there are relatively easy ways to control servos with an Arduino board or a Raspberry Pi, but you’ll have to do some programming, it’s not cheap, and you’ll need to breadboard some components. It’s kind of a hassle.

As an alternative, you can get a small, cheap, servo tester like this. You can get them smaller and cheaper, but this $10 one from LewannSoul has some nice extras.

On the left side you plug in power, anything between 4-8v. The voltage gets displayed here on the little readout. The terminal block takes any kind of bare wire from a power supply. The other socket here can connect to the 3-prong balance cable of common 7.4v RC LiPo batteries.

Next to the terminal block you have two sets of servo connections. With these you can hook up either one or two servos and control them simultaneously. On the right side you have this nice knob that gives you a full range of control on the servos. Below that is a toggle button that returns the servos to its center position.

I learned about servo control boards from Jonathan Odom’s project on making this animatronic 3D printed robot puppet. He used five of them to manually animate his puppet. And for what it’s worth LewannSoul has another board that lets you connect and control up to 6 servos, but I haven’t tried it yet.

More than anything, I just love how this cheap board gives you a quick way to play around with servos. Last weekend I used cardboard and some magazine cutouts to quickly mock up a silly design after dinner that would probably have taken me an hour to put together with an Arduino.

-- Donald Bell 06/12/18