If you need to test your new circuit’s response to various signals, a dedicated function generator can be quite a useful tool. You could buy one, but this would obviously be less fun — and wouldn’t give you control over how it’s constructed — or you could instead build your own based on this design by “Faransky.”
Notably, this function generator features only a single rotary input for control, using a built-in pushbutton to cycle through different options. These include selections for the type of signal, frequency, and amplitude, as well as letting you adjust the display brightness as needed. Output is via an RCA jack, and the device can be charged and programmed using a USB connector.
An Arduino Nano serves as the brains of the operation, which interfaces with a CJMCU-AD9833 function generator module to output the needed waveforms, and visual feedback is handled by the popular 1602A 2-line LCD display. Finally, the device features a 3.7V rechargeable battery along with a boost converter to satisfy the Arduino’s 5V needs, allowing it to be used without a power supply when needed.
As seen in the video below, it’s a nice compact design that would be a welcome addition to any test bench or portable electronics testing bag!