Custom ESP32-S3 development board — professionally manufactured by JLCPCB. A far cry from where it all started. It Started in a School Science Lab — Around 1998 Most people who get into electronics start with a kit, a tutorial, maybe a breadboard and some LEDs. I started by sneaking ferric chloride out of a school science lab to etch my first PCB. That was around 1998. I was living in the Maldives — a small island nation in the Indian Ocean — where there was no electronics supply chain, no maker community, no local PCB fab. Just a chemistry cabinet at school, a copper-clad board from somewhere, and a lot of curiosity. This post is about what the next 25+ years of PCB prototyping looked like from there. The early wins with proper chemicals, the years of improvisation when those chemicals disappeared, the real injuries, the failed boards, and finally — the moment JLCPCB changed ever...
Today i completed the DTMF decoding circuit and interface it to the micro controller and DTMF tone was generated by the PC and fed to the decoder. After all the connections i wrote a test code for micro controller to get the decoded signal. With an interrupt i manage to get the decoded values from the tone generated.
To view what i am getting i connected the LCD and found some problems and after a while i menage to fix it. from the flow you can see how it works. Then i have to test this from a mobile phone and for that i need to make a small preamplifier to control the volume.
Comments