Battery-powered minimal ST-4 dither timer for iOptron HEM27EC: two AAA cells, ATtiny1616 controller, opto-isolated RA+/RA-/DEC+/DEC- contact closures, physical interval/intensity selectors, DITHER NOW button, and low-power status LED. The previous ESP32-S3 USB-host design is preserved only as a conditional V2 archive.
18 V battery-powered BLDC blower control board using an Arduino Nano, LM2596 5 V buck module, P-channel MOSFET power cutoff, battery voltage sensing, potentiometer input, buzzer, and red/green status LEDs. High-current 18 V blower path is sized for up to 5 A.
Battery-powered smart pet collar PCB with ESP32-class wireless MCU, GPS, heart sensing, temperature, motion sensing, microphone, USB programming, and mobile-app data connectivity.
Hand-solderable 9V battery-powered red LED blinker using a 555 timer in astable mode, an on/off switch, and through-hole support components for approximately one blink per second.
Compact ESP32-C3 battery-powered pickleball telemetry tracker with high-g IMU, local flash buffering, USB-C LiPo charging, and Wi-Fi/BLE data transmission.
ESP32-C3 battery-powered pH and ORP probe interface using ADS1115 differential ADC, MCP6002 through-hole buffers, DS18B20 temperature compensation, and short net labels for firmware handoff.
Battery-powered ESP32-S3 LoRa ePaper sensor board with SHT41 environmental sensing, LiPo charging/fuel gauge, 5V input detection, and a 4.2 inch 300x400 b&w ePaper interface in an 85 x 60 mm low-profile PCB.
4-layer ESP32-S3 controller for a dual V-mount battery-powered film fog generator with 200 W heater PWM, pump/fan outputs, K-type thermocouple sensing, battery monitoring, and DMX-512 control.
Production-ready industrial 6 V battery-powered LoRaWAN DC motor controller using ESP32-S3FN8, SX1262 AU915, CP2102N USB-C programming, DRV8833 motor drive, TLV62568 buck regulation, protected battery input, and Heltec LoRa V3-compatible development workflow.
4-layer ESP32-S3 controller for a dual V-mount battery-powered film fog generator with 200 W heater PWM, pump/fan outputs, K-type thermocouple sensing, battery monitoring, and DMX-512 control.
Battery-powered infrared/PIR sensor board with USB-C charging, single-cell LiPo battery input, 3.3 V regulation, sensor output header, and status indicators.
Battery-powered ESP32-C6 Thread environmental sensor using SCD41 for temperature and CO2, USB-C for charging/data, LiPo power, and a buck-boost 3.3 V rail.
Hand-solderable 9V battery-powered red LED blinker using a 555 timer, on/off switch, and through-hole support components for approximately one blink per second.
Through-hole 9V battery-powered 555 timer circuit that blinks a red LED approximately once per second using an on/off switch and hand-solderable components.
