A Simple Signal Generator

I was searching for radio-oriented applications for the little £3.90 Raspberry Pi Pico microcontroller board. One thing I found was a simple signal generator that uses the Pico in conjunction with the Si5351A chip to generate square wave signals from 440 kHz up to 149 MHz or so:

https://community.element14.com/products/raspberry-pi/raspberrypi_projects/b/blog/posts/picosynthrf---a-python-based-rf-signal-generator

Cost is under £25 for all the parts, including the PCB. It is intended for home construction, but isn't really a beginner's project as it involves surface mount devices. It should be possible, if enough people are interested, to get the PCB supplier to assemble most of the parts.

The Si5351A is crystal-controlled and generates a very stable signal. Resolution is approximately 1 Hz! It's used in several QRP radios.


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