Help. Wiring an LED

[gizmo911uk]

Is there a way I can wire up an LED to its own power supply (5v) and use the current coming in from an other source as a switch. I do not want to draw the current away from this other source.

 

[bogdanfirst]

coud you be more exact....details....
if you just want to wire a LED to a 5V suply just connect a series resistor of 220 ohm for example and connect the led and the resistor to the suply...
if you want another thing please be more exact....

 

[Pilot]

Use a transistor to turn it on.

uA into the base to switch it. Have the led on its own 5v line.

 

[daviddoria]

from pilots idea:

http://www.bandtank.com/~calculusap/transistor.wmf

enjoy

 

[gizmo911uk]

The Project that i am working on is a hard hisk drive switch, basicily it is a double pole double through switch with 2 sets of wires going to the master jumper (replaced std 2.54mm jumper with a 2 way 2.54mm PCB socket) to turn on.

What actual triggers the transister to switch?