Welcome to the lessons page!

New lessons on electronics are being prepared and will appear soon. If there is anything you would like to be covered, please contact us and ask!

We believe that as you learn electronics your world becomes bigger, richer and more inspiring. 

Electronic boardWith a handful of semiconductors, a breadboard, a soldering iron and some wires, you should be able to create just about anything you like. Don’t give up every time blue smoke pours out of a transistor, or when a circuit does something completely unexpected, it’s all part of this game. Learn as you go, using the Internet, reference books, and other people’s designs as a guide and, before long, you will be able to whip up any type of circuit without any reference material at all.


When we talk about rectifiers, the first thing that comes to mind is power supplies, but rectifiers are also used in many other circuits. Converting AC to DC is necessary in many high-precision signal processing circuits, and most circuits that measure real-world quantities first have to rectify sensor voltages. But even though regular diodes and bridges are adequate for many rectifying jobs, sometimes a different approach is needed.

Here, we explain the general concept of using an operational amplifier for voltage regulation. By utilizing an op-amp and few other external components, we can easily build a linear voltage regulator. Apart for being a regulator, the same circuit is also a voltage stabilizer, able to stabilize voltage at a grade better than 0.01%. The circuit is powered from a non-stabilized DC-power source, and uses a transistor (T1) inside a feedback loop. The transistor is used to supply the load with much more current than the op-amp itself could possibly supply. The D1 diode is a Zener - type  diode and it is used for voltage reference.

In the current article, we will turn our attention to the basic concepts of Linear Power Supplies. All circuits require some source of power to operate and the most convenient source of such power is an AC wall outlet. Unfortunately, most of electronic circuits cannot make use of AC directly. Instead, some way to convert the AC to DC is required.


An LC oscillator is actually a feedback oscillator which uses capacitors and inductors in its feedback network. It can be built from a transistor, an operational amplifier, a tube, or some other active (amplifying) device. Oscillation is brought about by applying a portion of the amplifiers’ output signal to its input. That feedback signal must be applied in phase with the original input signal. The amplifier is usually an inverter that provides 180o of phase shift by itself, and an additional 180o of phase shift must be provided through some other means.

By reading the article below we hope that you will become familiar with the basics of the amazing 555 timer. After being familiar with the basics, you may refer to the 555 circuits section of our website to explore many more.

Many systems require an input in the form of a periodic, usually sinusoidal, waveform. The periodic signal is generated from a special circuit which is known as the “oscillator”. Oscillators convert direct current (DC) from a power supply to an alternating current signal. They are widely used in many electronic devices. Common examples of signals generated by oscillators include clock signals, sounds produced by electronic beepers and video games, and radio frequency signals used for broadcasting.