Resistor for Transistor Calculator?

[SergioQ]

Hello all,

Am new to electronics and playing around is all. I bout an NPN transistor from radioshack, but when I look up any online resistor calculators none of the fields they ask for, are on the data sheet for the transistor.

Am assuming that perhaps they're using different terminolgy, thought I'd reach out for some help.

Also, really just want to use this for a switch to light up an LED or two. Not even sure if it's too much or too little for a 6V battery supply.

Many thanks,

Sergio

TIP120 Darlington Transistor
Power Dissipation 65W
Collector-emitter voltage 60V
Collector-base coltage 60V
Emitter base V 5V
Collector current (cont) 5.0A
Collecor curretn peak 8.0A
Base current 120mA
Unclamped inductove load energy 50mj

[pebe]

Hi Sergio. You have bought a 50A transistor to switch about 15mA to light an LED. You have certainly got a 'sledgehammer to crack a walnut'!

An explanation of what you require would take up a lot of space, so I think you would be better off if you look to a tutorial. The one at this site explains things fairly easily and should provide answers for you. Look under 'Transistors'.

http://www.williamson-labs.com/