VK4ADC is an Australian amateur radio operator whose on-air activities include weak signal/microwave work. As such, he needed a reliable tone generator to modulate his transmitted RF carrier to permit receiving stations to peak their station’s antenna for maximum signal. So he decided to design his own multi-function tone generator around the Picaxe 08-M.
Accustomed to microwave circuit design which requires miniature dimensions, his project was built on a 35mm by 35mm board. The circuit consists of a standard 8-pin DIL PICAXE (an 08M), a 5-volt SMD regulator, an SMD-style LM386 audio amplifier plus extra SMD components for easy switching and filtering.
You can find all the details on how this project progressed from concept to the finished product shown above, along with the Picaxe code and schematic at VJ4ADC’s website.
For information on the Picaxe line of MCUs, and to download their free programming IDEs for Linux, Mac and Windows, visit the Picaxe website.