When I was childhood, I always curious about how electronic circuitry works. I remembered when I wanted to build a transistor audio amplifier, but didn't have any supporting knowledge. Internet hadn't come to my place at that time, not like today. Well, I need some time to build and test all those circuits. Even if I can design a much more complicated circuit than a simple audio amplifier today, but recalling the romance of the past is always exciting. Someday, when knowledge is no longer needed for my work, I will use it for myself fun.
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1. Class AB 4 Transistor Amplifier
2. Class A Headphone amplifier
3. Small audio amplifier circuit diagram
4. Power Amplifier OTL Cassette Radio Booster by TIP41+TIP42
5. Power Amplifier Class A by Transistor
6. Mic/Guitar Compressor with Transistor Bias Control
7. 50 mW 3 Transistors Amplifier
https://www.eleccircuit.com/4-transistor-audio-amplifier-circuit/
https://www.deeptronic.com/electronic-circuit-design/small-audio-power-amplifier-using-3-transistors/
http://www.bowdenshobbycircuits.info/page8.htm
