[_Microft]

Analog electronics [0] uses a continuously variable signal while digital electronics interprets the signal with thresholds that define states like 0 and 1.

Here is a simple example: using a few discrete parts, like two transistors (Darlington pair), a LED and resistor, you can create a simple circuit that shows varying brightness of the LED depending on how close you move your hand or an object to an antenna connected to one of the transistors (forming a sort of proximity sensor). No microcontroller, SBC or even a hint of a digital signal involved at all.

[0] https://en.m.wikipedia.org/wiki/Analogue_electronics

[rramadass]

> Here is a simple example: using a few discrete parts, like two transistors (Darlington pair), a LED and resistor, you can create a simple circuit that shows varying brightness of the LED depending on how close you move your hand or an object to an antenna connected to one of the transistors (forming a sort of proximity sensor)

Do you have some book/video/etc. recommendations for this "type" of Electrical/Electronics circuit engineering? I only know how to program a MCU :-(