Preview of cascading NPN and PNP transistor circuit demonstratio…
I rushed this video and didn't mention a few things. The resistors connecting the transistors are both 10K resistors. The resistors protecting the LEDs are both 220 ohm resistors.
Using a single bipolar junction transistor as an emitter amplifier voltage source has one annoying issue in that you lose the base-emitter voltage of about 0.6V. You can cascade a NPN and PNP transistor, in this case the 2N3904 NPN and the 2N3906 PNP, to remove almost all off that voltage drop within certain limits.
This video is just a quick demonstration of the cascading NPN and PNP transistors. I will cover this more when I get time in the future
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