LED Flashlight in 30 seconds!

 by fundash
guitar-is-awesome says: Sep 4, 2010. 2:57 PM
could you do it with one LED? and solder wire to lengthen positive and negative? either that or use cell batteries? im sorry, im really inexperienced in LEDs and am trying to make a small LED light system - LED(s), rocker switch, cell batteries or lengthened pos and neg wires. to wire up to a mask :)
Anthony312 in reply to guitar-is-awesomeSep 5, 2010. 9:00 PM
It would no twork. You would need a resistor and need to calculate the ohms needed for this resister.
.Unknown. in reply to guitar-is-awesomeSep 5, 2010. 5:26 AM
You could put one or more LEDs in parallel to a cell phone battery, was it? No, you can't just put one LED to a 9V battery, (unless you have a resistor or some other regulator.) a switch can go in between either terminal of the LED and the battery.
mytree says: Sep 5, 2010. 4:56 AM
Do I have to pull off the battery each time to switch off the light ? I am a novice at this stuff & I really dont understand how an 'on/off ' mechanism is built into these circuits. Can someone help?
.Unknown. in reply to mytreeSep 5, 2010. 5:22 AM
In this particular set up, yes.
fundash (author) in reply to .Unknown.Sep 5, 2010. 11:20 AM
yea, you just take the battery off
paperairplanecreator says: Sep 2, 2010. 4:46 PM
ummm where do you get the LED'S?
devinda in reply to paperairplanecreatorSep 3, 2010. 2:18 AM
dude, you can get hthem in any electriacal shop, for me it costs around $0.04 (usd)
fundash (author) in reply to devindaSep 4, 2010. 1:16 PM
ya, that to...but unfortunatly, my local store has them for .50 a piece, the pack of 1000 I got off eBay was .015 an LED, Thats only one and a HALF pennies!!! :D
paperairplanecreator in reply to devindaSep 3, 2010. 10:30 AM
thanks dude! youve saved me alot of time!
fundash (author) in reply to paperairplanecreatorSep 2, 2010. 5:59 PM
You can order them off Ebay, I got a pack of 1000. also out of other things like booklights have LED's in them.
dad45 says: Sep 1, 2010. 7:21 PM
No problems with them burning out? 9V is a little high with no resistor in the circuit. Keeping it simple is good but you probably could use a resistor (if you ask what value I'm guessing 100 ohms but there are calculator online for a better answer) You know those little LED flashlights that go for $2 - $3? They use 3 AAA so that's only 4.5 volts. You could also bundle up 3 AAA's.
fundash (author) in reply to dad45Sep 1, 2010. 8:19 PM
well, this is fine for now, the third LED acts as the resistor (But the LEDs arn't at 100% brightness.)
pandyaketan says: Sep 1, 2010. 1:51 AM
5 * !! What i do is generally bend the + & - ends so that the LEDs sit on the + & - of the 9v battery. that way you dont have to hold it constantly and can work even as table light / mood light / night lamp, etc. it could last upto 50 hrs.... i have some i'bles on leds.... reg, ketan
fundash (author) in reply to pandyaketanSep 1, 2010. 9:19 AM
yea, thats nice, thanks for the comment! :)
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