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Can I have a quick hand putting this simple circuit together? Answered

I've begun to try to put together this circuit myself. I have all the parts, but I'm horrible at reading schemas. I've failed 4 times now, and only managed to get a little movement from the motor once. I've read a couple tutorials on reading schemas, so I know most of the symbols, but actually putting them together is a whole new deal for me. I'm trying to get a photo cell to regulate the power of a motor without starving it of power. Could someone please give me a bit of direction as to how I solder the parts together (i.e. solder resistor to the left lead of the transistor etc.)? Thank you for the help. :)


transistor 12v

10 years ago

Solder the motor and the resistor to the + 9v battery. Then solder the other end of the resistor to the photocell and connect the second pin of the photocell to the base (middle pin) of the transistor. Attach the other pin of the motor and the - side of the diode to the collector (right pin loking at the flat side) of the transistor.Finally solder the + side of the diode and the emitter (left pin looking at the flat side) of the transistor to the - wire on the battery.


10 years ago

It all very much depends on what transistor you're using as to which pin is which. I suggest you get the datasheet for your exact one and find the pinout there. When you find that out, the diagram there shows the photocell connected to the Base of the transistor, the negative from the motor to the Collector, and Emitter to ground. The diode is connected with the negative side to the Emitter, and the positive side to the Collector. Hope that helps some.


Answer 10 years ago

Gah, wrong way around. The diode has negative to Collector and positive to Emitter.