Builds: every letsBug electronics build

Electronics builds with the ESP32: the circuit, the resistor maths and the code. Each post goes with a letsBug video.

1. ESP32 LED blink: code, circuit and the resistor you need: ESP32 LED blink for beginners: wire an LED to GPIO 23, work out the resistor with Ohm's law, upload the Arduino code, and skip the risky pins.
2. What is a bit and a byte? Logic gates using switches: What is a bit and a byte? A bit is 0 or 1, like one switch; eight bits make a byte with 256 patterns. Plus AND and OR gates from two switches.
3. Transistor as a switch: build a NOT gate with one transistor: How a transistor works as a switch: a 2N2222, an LED and a 10 kΩ base resistor, the base current worked out, then one transistor as a NOT gate.
4. AND gate and OR gate using transistors: build both: How to make an AND gate and an OR gate using transistors: two 2N2222s in a row or side by side, the LED current, and NAND at the top of the stack.

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