Using Arduino IDE, the ESP32 reads environmental data, stores it with timestamps on a microSD card, and serves a web page that displays live charts plus temperature stats such as time to max temp and periods above or below set values.

Just pick your op-amp type, enter resistor values and optional input voltage, and this calculator instantly shows you voltage gain, output voltage, and gain in decibels for both non-inverting and inverting setups. It updates as you type and even lets you copy results with one click.

RetroClock started as a simple ESP32 project but now offers a full package: hourly weather icons, a crypto ticker with six assets and price alerts, an alarm clock, and egg timer. It keeps time via internet sync and lets you tweak display settings and alarms easily through your phone.

This single-ended amplifier uses a PCL82 tube and modern DC-DC power supplies to produce 2 watts of smooth tube sound, completely free of audible hum or switching noise. The design keeps components minimal and is suitable for stereo setups with two amps.

The ESP32-2432S028R, aka the Cheap Yellow Display, combines an ESP32-WROOM-32 with a colour touchscreen, microSD slot, RGB LED, light sensor, and speaker circuit in one ready-to-use board. Here are five simple projects you can explore and build today without any deep coding or wiring hassles.

Instead of cluttering your Arduino nano with lots of LCD wires, I2C lets you connect character and OLED displays using just SDA and SCL lines. Learn about the internal operation of these displays and see how to wire and program 16×2 LCDs and SSD1306 OLEDs over I2C.

This project uses PNP and NPN transistors to create a smart restroom indicator without any coding or cloud connection, relying on basic switching logic to detect latch status and control LEDs for occupancy signals.

The common collector setup connects the collector to both input and output, with signals applied between base and collector and output taken from emitter to collector. This tutorial covers the common collector configuration for NPN and PNP transistors, current relations, characteristics, key parameters, and how it stacks up against other transistor configurations.

This unusual SDR design relies on the MCP2036 IC plus a few passive components and an external VFO to create a direct conversion radio receiver covering roughly 10–15 MHz. Instead of complex hardware, it uses SDR software on a PC to process signals on several HF and shortwave bands.

The KTS1630 safeguards sensitive electronics by detecting overcurrent in about 100 ns and shutting down before damage occurs. It supports input voltages from 4.5 V to 18 V, has a low on-resistance MOSFET, and offers programmable current limits and output slew rates.

Using a Seeed Studio XIAO ESP32-S3 and a ring of eight electrodes on its rear, EITWatch captures hand gestures by tracking electrical impedance shifts caused by muscles under the skin, without needing wristbands.

Using an ESP8266 NodeMCU and Arduino IDE, this project fetches word meanings, synonyms, and antonyms from online APIs instantly over Wi-Fi. It's a neat demonstration of how embedded systems can handle web requests and JSON data without storing tons of definitions locally.

For the visually impaired, who use a cane, VisuPath combines computer vision and proximity sensors on an Arduino UNO Q to detect objects ahead, filter important threats, and provide alerts via vibrations and voice, to help navigate crowded or unfamiliar places beyond the cane’s normal reach.

Introduced in 1977, the TL072 uses TI’s BiFET process to combine JFET inputs with bipolar outputs, reducing input current and noise compared to older op amps, and quickly becoming the standard in audio circuits.