[Rupert]’s IC is just three parts, a 2n2222 transistor, a 220Ω resistor and an IR LED. With a good bit of deadbug soldering, these three parts were melded into something that resembled ...

Transistors want current control ... A reasonable choice of BJT is the venerable 2N2222. It’s available worldwide, is very inexpensive, reasonably fast, and can dissipate up to 500 milliwatts ...