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Need Help Making Circuit Answered

I am working on a small weekend project that involves taking the power from the location on the PCB in a keyboard where the LEDs were and making it act as a switch to a small remote control outlet (Something Like This: http://ecx.images-amazon.com/images/I/410y7UnyvdL.jpg )

I have tried using an LED glued to a photocell, though I am thinking it is somehow acting as a resistor and limiting the power that can go through. I have some transistors, What kind of a circuit can I rig up with them to make this work?

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user
11010010110 (author)2009-01-17

the switched device and the led should have common earth. the transistor switches the device from the earth side the extra resistor is about 470 ohm for small npn txistor (like C945) at 5 V. if the led allready had resistor you should only add resistor so that together they are about 470 ohm the needed value may change depending on many factors

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user
11010010110 (author)2009-01-17

still why not a transistor ? you can use it directly and not like the photo cell for stuff powered from low volt you dont need the relay

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user
11010010110 (author)2009-01-16

you need small npn transistor and relay and very good isolation so that in no wai 110 / 240 V can get to the computer you can do this as well on the old printer port

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