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...
Long time back i have posted on regarding a voltmeter. I know it took long time to complete it. But this completion is quit modified from my older design. I used an PIC16F88 which has 7 ADC channels .Keke i used only one at the moment. But have many thoughts for an upgrade sometime later. Everyone will think how this fella works. How it works? The circuit was design for two different parts. One is Analog side and other one is Digital side. Analog side does all the voltage conversion part for the micro controller. This was done by an LM358 which is an Operational amplifier, otherwise known as Op-Amp. Huge value of voltage will damage the micro controller. The input voltage for Micro controller should not exceed 5V so this part is handle by the analog circuit. Next is digital part which is the micro controller part which does all computing and display the result. This circuit is complicated for a newbie cause i used shift registers to handle the 7 segment displays. Micro controller outpu...