Hi Jpop,
Just about any little NPN transistors will work in that circuit. Its supply is only 3V and the LED driver's current is only about 25mA.
I would use 2N3904 transistors. ;D
Think 2N3704 would do the job and as audioguru said Just about any little NPN transistors will work.
I don't know which is the most used UNI transistor in US so my choise is just a guess of what would be a handy replacement for the BC337 ;D
Yes, even a 2N3704 transistor will work. Digikey sells them for $.30US each.
They sell the 2N3904 for $.16US each because they are more popular.
They sell the BC337 for $.33US each. ;D
I thought the 2N2222A ina plastic case is the PN2222A, by the way how come there seem to be still loads of metal cased transistors on the market when I haven't seen a single one in a piece of modern consumer electronic equipment?
Hi Alun,
You can still buy metal-cased 2N2222A transistors at Digikey for $.86US each, but there is only one supplier (ST Micro).
ON Semi make the best of both worlds, a P2N2222A in a plastic case!