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    londonlad reacted to ike in Total Noob Q'n, Need Help Controlling a Transistor   
    You need to connect GND too. For current to flow you need 2 wires. And you may try with 1k ohm resistors instead of 10k.
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    londonlad reacted to grahamf72 in Total Noob Q'n, Need Help Controlling a Transistor   
    You're nearly there, your main problem is the 10k resistor in the emitter line. This reduces the current that can flow through the led to a minuscule amount. The correct configuration is to put the current limiting resistor in the collector line. Hopefully the following sketch will show how.

    The value of the collector resistor will vary depending on the forward voltage of the led (typically around 3v) and the current of the led (typically around 20mA). The value is determined by (Vs -Vf)/If, where Vs is the supply voltage, Vf is the led forward voltage and If is the led forward current. Using typical values we get (6-3)/.02 = 150ohm.
    Sent from my iPad using Tapatalk
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