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Power LED's - simplest light with constant-current circuit

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Step 4: Start building the circuit!

this circuit is so simple, i'm going to build it without a circuit board. i'll just connect the leads of the parts in mid-air! but you can use a small proto-board if you want (see photos at the end for an example).

first, identify the pins on Q1 and Q2. laying the parts in front of you with the labels up and the pins down, pin 1 is on the left and pin 3 is on the right.

comparing to the schematic:
Q2:
G = pin 1
D = pin 2
S = pin 3

Q1:
E = pin 1
B = pin 2
C = pin 3

so: start by connecting the wire from the LED-negative to pin 2 of Q2