Voltage Controlled Oscillator

Need an oscillator whose output frequency is adjustable with a voltage? Then look no further, as this kit by MitchElectronics will let you build a voltage-controlled oscillator!

An excellent project for beginners and learners alike!

The Voltage Controlled Oscillator (VCO for short), is a very practical circuit for generating square and sine waves. While these waves can be produced using the Simple Function Generator Kit, the VCO allows for controlling the output frequency with the use of a voltage signal instead o using a potentiometer. This means that the output frequency of the VCO can easily be controlled by microcontrollers and other analogue circuits which can create some pretty interesting results. For example, a 1V octave synthesiser can be built using this module whereby a 1V octave keyboard is connected to an exponential converter which feeds its output into the VCO to produce keyboard tones. This circuit can also be used in retro ways such as sensor data transmission where the voltage output of a sensor is converted into a frequency and the frequency of the output will be proportional to the sensor reading (a similar system was done in early satellites such as Sputnik).

PWM Generator 

If you are in need of a PWM signal source for testing purposes then look no further as this kit by MitchElectronics will let you create your own PWM generator! Perfect for beginners!

PWM Signals are those that have variable duty cycles and are found in many thousands of circuits. Just a few examples of how PWM signals can be used include Digital-To-Analog conversion, high-efficiency power controllers, servo control, timing, and much more. This kit will allow you to build a simple PWM generator that runs on voltages between 5V-28V and has two potentiometers for adjusting both the frequency of the PWM wave and the duty cycle between 0% and 100%.

Simple Function Generator

Need a basic function generator with variable triangular and square waveforms? Then look no further as this kit by MitchElectronics will allow you to build your own simple function generator! Excellent project for beginners and learners alike!

In just about every electronic circuit there will be some signal that changes with time and in many circuits, this signal may be continuous. For example, the electricity from the mains supply has a sinusoidal shape (like an ocean wave). Another example would be the clock for a computer that has a square shape.

Imagine a scenario where a digital circuit has been created and requires a clock from an external source. One could be built especially for the task however the clock source would most likely have a fixed frequency. Even if one was designed to have a variable frequency (which takes time), the device would only output a square wave. This is where the humble function generator steps in!

Not only does the SFG (Simple Function Generator), have both a square and triangle output but the frequency is also adjustable. The square and triangle wave are generated by the same source and thus are always in the same phase which means that the two waveforms follow each other constantly (useful if both waves are being used). But how does this circuit work? What active devices are used to create the oscillations and how is the frequency adjusted? Let’s find out!

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