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Tutorials In Electronics

Servo Motor Control Systems

Servo motor

Let me show you how servo motors work and what you need to do to drive them. There's a handy library that you can use with Android which makes things very easy called 'Servo'. But what if you need to drive the servo some other way? If that's the case then you will need to know something about how they work.

I will show you how to connect one up and write a very simple Arduino sketch to experiment with. I explain exactly what goes on inside a servomotor and I finish up with a set of oscilloscope traces. If you want to know more about servo motors then read on. More...

Sony Vaio Fan replacement

My Sony Vaio laptop was 2 years old when the cooling fan started to become noisy. Normally you would hear a faint whirring noise with a note that changed as the temperature control system altered the fan speed. This had become a noisy rattly sound that was quite objectionable.

So I ordered a replacement fan and set about the daunting task of changing it in my Vaio. As it turns out the process was not as difficult as I had expected it to be which was quite a relief. This is how I did it... More...

How To Measure Output Impedance The Easy Way

Z is for Impedance

Output impedance can seem a bit like black magic until you realize that it's really quite simple. Here is an easy yet effective way of measuring the output impedance of almost any circuit. I've avoided turning this into a full-on mathematical treatment of impedance that would bore you to tears. Instead I give you an easy to understand practical feel to the problem instead.


Sound Card Oscilloscope and Multivibrators

Part of a multivib circuit

What can a sound card oscilloscope do for me? This is the question I get asked a lot and I usually say something along the lines of "No engineer can do without one". Not many people find this very helpful so I've built a simple astable multivibrator and applied the oscilloscope to it. In trying to explain what the waveforms mean I hope to answer the question better.


Soldering Is Easy

Soldering iron drawing Soldering is easy as this excellent comic strip from illustrates. If you have any doubts at all about your ability to master the useful skill of soldering then you should read this. It's fun, it's entertaining and it's easy. More...

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