Hello,
I'm working through the transistor section of the site and I'm having some problems with simple circuits I've built to test my understanding. Hopefully someone can enlighten me as to what I'm doing wrong.
I've attached a schematic of two simple circuits I've built. The idea is that as I turn the pot clockwise the led should go from completely lit to dark. (I've connected the leftmost and centre pin, looking from the top.) In practice the first version of the circuit (A) works as expected, version B doesn't (the led stays off whatever). Why not?
I've looked up a datasheet for the bc548b transistor, and have also confirmed the pins using the meter check method described here. Unless I've made a stupid mistake I think I'm hooking it up right.
Am I wrong to think they should both work?
Any suggestions are greatly appreciated, as I don't think I can progress without some pointers! Thanks in advance.
Luke
I'm working through the transistor section of the site and I'm having some problems with simple circuits I've built to test my understanding. Hopefully someone can enlighten me as to what I'm doing wrong.
I've attached a schematic of two simple circuits I've built. The idea is that as I turn the pot clockwise the led should go from completely lit to dark. (I've connected the leftmost and centre pin, looking from the top.) In practice the first version of the circuit (A) works as expected, version B doesn't (the led stays off whatever). Why not?
I've looked up a datasheet for the bc548b transistor, and have also confirmed the pins using the meter check method described here. Unless I've made a stupid mistake I think I'm hooking it up right.
Am I wrong to think they should both work?
Any suggestions are greatly appreciated, as I don't think I can progress without some pointers! Thanks in advance.
Luke
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