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Hi, I am Gursimran Singh
In this Instructable, I will guide you through on how to make a “functional” function generator, which can be very helpful when working with electronic circuits. A function generator can generate different kinds of signals like sine wave, square wave or even a triangular wave at a particular frequency set by the user.
The design explained in this ible uses AD9833 which can ideally generate frequencies up to 12.5 MHz as per the datasheet. I came across AD9833 when reading this project by Cezar Chirila.
I will explain the problems I encountered and how I got rid of them in upcoming steps. Also, you’ll learn how to fabricate your own PCB at home.
This project is powered by AC Mains Supply (220 Volts), playing with electricity is not a good idea. If you are interested in making this project ,then please make it under the supervision of a professional, Electricity can be lethal!

The 3 LEDs indicate the wave to be synthesized (Red for Triangle, Green for Sine and Blue for Square Wave), each of them can be selected by the horizontal black rectangular switch.

The first knob (potentiometer) from the left controls the amplitude of output, maximum is 12 volts.

The middle knob (potentiometer) controls the offset voltage of output.

The Red knob is attached to a rotary encoder which is used to set the frequency, basically scroll the encoder clockwise and anti-clockwise to move the pointer (A decimal on 7-Segment :P) right and left respectively to a desired place.

Once on the desired place button(Rotary Encoder’s Push Button) is pressed, pointer is locked at that position now scroll the encoder to increase or decrease the number value at the place. Pressing the button once again sets the value at the respective place and now encoder can be scrolled to move on any other place.

I know I couldn’t explain the whole mechanism of rotary encoder properly :)”

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