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 This innovative Digital Glass Clock is built using the ESP32-C3 Mini, two MAX7219 LED matrix display modules, an MPU-axis motion sensor, a rechargeable 800mAh lithium battery, and an onboard charging module. Inspired by a traditional sand clock (hourglass), the device automatically detects its orientation using the MPU sensor and displays animated digital sand flowing from one side to the other. 

This Project is originally created by  

意昂老师的模型之家

https://makerworld.com/en/models/2668408-electronic-hourglass-timer#profileId-2953155

 This ESP8266 Mini Relay board is a compact WiFi-enabled smart controller designed for home automation and IoT applications. It features 4 high-quality relays, a 1.3-inch OLED display, onboard RTC (real-time clock), WS2812 Pixel LED output, and built-in WiFi configuration using AP mode. The board allows real-time relay control, time scheduling, status display, and mobile-friendly web dashboard access. Ideal for smart home projects, industrial automation, lighting control, and remote switching systems 

 This DC to DC buck converter circuit is designed using the LM2576-5 switching regulator, ideal for converting 7V to 36V DC input into a stable 5V DC output. The compact PCB layout ensures high efficiency, low heat dissipation, and reliable performance in industrial and embedded applications.

This module is perfect for PLC systems, Arduino projects, ESP32 / ESP8266 boards, IoT devices, relay controllers, LED drivers, and automation panels where a stable 5V power supply is required from a 12V or 24V DC source.

 This industrial-grade 4-channel opto-isolated interface card is designed to safely interface PLC digital outputs with external driver or control circuits. Each channel uses PC817 optocouplers to provide reliable galvanic isolation between field wiring and control electronics. 

🔹 Key Features:

• 4 Independent Opto-Isolated Channels
• PC817 Industrial Optocouplers
•  24V PLC Compatible Inputs
•  1N4007 Reverse Polarity Protection
•  RC Noise Filtering for Stable Operation
   

This compact and reliable ATmega8 / ATmega328 target board is designed for easy programming, bootloading, and development of DIP-based AVR microcontrollers. Ideal for hobbyists, students, and embedded engineers, the board provides a stable platform for testing and deploying Arduino-compatible projects.

The board includes an onboard crystal oscillator, decoupling capacitors, reset circuitry, and a standard ISP header for seamless programming using USBasp, AVRISP, or Arduino as ISP. Its minimal yet efficient design ensures quick setup and reduced wiring complexity during development.

Perfect for prototyping, firmware testing, and standalone embedded applications, this target board supports both ATmega8 and ATmega328 DIP variants, making it a versatile choice for AVR-based designs.

🔹 Key Features:

• Supports ATmega8 and ATmega328 (DIP package) 
• Standard 6-pin ISP programming header 
• Onboard crystal oscillator for stable operation 
• Compact and easy-to-use layout 
• Ideal for bootloader burning and firmware development 
• Minimal external components required
   

The ESP8266 RTC Digital Clock is a compact and reliable clock project built using the ESP8266 WiFi module, DS3231 Real-Time Clock (RTC), and MAX7219 4-digit LED display. This project combines internet time synchronization with hardware RTC backup to provide accurate time even during power interruptions.

The bright 4-digit LED display offers excellent visibility from a distance, making it suitable for homes, offices, workshops, classrooms, and industrial applications. When connected to WiFi, the ESP8266 automatically synchronizes with NTP servers to maintain precise time. If the internet connection is unavailable, the DS3231 RTC module continues keeping accurate time independently.