How to use the BC547 Transistor (NPN) (with examples) - DIY Engineers
arduino - BC547/BC548 with 5V at base can't control 12V at collector-emitter? - Electrical Engineering Stack Exchange
Different use cases of BC547, 2N3904 and 2N2222
Voltage Controlled Switch by BC547 - EEWeb
Touch Switch Circuit using Transistor
How to connect a BC547 transistor for making a switching circuit - Quora
What is the Difference Between BC547 Transistor vs 2N2222 Transistor? | Global AI and Data Science
Embedded Life: Make a simple touch switch using BC547 for LED, RELAY,BUZZER
BC547 Transistor ON Touch Switch Circuit – Earth Bondhon
Transistor as a Switch | Breadboard | Maker Pro
Electronics Circuits Embedded PIC Micro Controller Tutorials : How to Calculate Base Resistance required for the Transistor / How to Drive a relay or a High Current Load using a Transistor