John H.

I am a senior electronics and embedded systems engineer with 47 years of experience in hardware design, firmware development, PCB layout, debugging, testing, and product development. I help clients turn electronic product ideas, prototypes, and hand-wired circuits into working embedded systems and manufacturable PCB designs. Typical projects I can help with include: * ESP32 and STM32 / STMicroelectronics MCU-based products * Power conversion and low-power battery-powered product design * Custom wireless and RF communications, including LoRa and ESP-NOW peer-to-peer networking * Circuit design and component selection for manufacturing * Schematic entry and multi-layer PCB design. * Ordering fabs and coordinating assembled boards. * C/C++ firmware for sensors, displays, audio, wireless, and control systems * Embedded graphics and touchscreen user interfaces using LVGL * Digital audio filtering, FFT spectrum analysis, and voice activity detection * Cloud API integration for speech-to-text, text-to-speech, and language translation * Embedded bus and peripheral interfaces: I2C, SPI, I2S, UART, RS-485, CAN, and SD/MMC * Prototype debugging and board bring-up * Converting breadboard prototypes into clean PCB designs * Design reviews before manufacturing * Analog and digital circuit troubleshooting * Production-oriented improvements for reliability and manufacturability I have founded and managed engineering companies and consulting firms, led technical teams, and helped bring electronic products from initial concept through prototype, testing, manufacturing, and production. For clients, this means fewer design mistakes, faster debugging, lower development risk, and a clearer path from concept to a working, manufacturable product.