Wirehead Studios

(http://www.speakeasy.org/~ltphil/LEDs.gif)

This lovely little circuit is a test design for my replacement turn signals... I've got a '72 chevy, and I'm going to eventually convert all the lights except the headlights over to LED...

Right now I'm powering it on 9V worth of NiMH AA batteries (1800mAh total) in series, and it's been going strong for over 10 hours... indicating to me that the current draw is less than 180mA... this is a good thing!  if i can get my taillights to run at less than 250mA, then my battery will last almost twice as long if i leave my headlights on... umm, not that i've ever done that...  :rolleyes:... not to mention, they'll never burn out in my lifetime  :)

looks like i spoke too soon... the LEDs are slowly starting to dim... after 11+ hours...  that's less than 160mA draw... i think that's pretty damn good.  

now i need 30 more amber LEDs (four front turn signals, minus this one i've already built), and about 60 red LEDs... 30 per tail light.  not sure how i'm going to configure them in my taillights yet, since i have to deal with the intensity difference for braking.  i think my taillights are dual-filament, so i could wire the standard taillight line through, say, a 200ohm resistor, and then the brakelight line through a 50ohm resistor (still need to actually calculate values)...  that way when my lights are on, the taillights are dim but still very visible, and then when i hit my brakes, they get significantly brighter.  any other ideas?   :unsure:

:ph34r:

why leds?

because LEDs:

1) don't burn out
2) draw much less current
3) have no warm-up/cool-down

not to mention, it's great to see the look on peoples' faces when i tell them i modded my '72 pickup and put a bunch of LEDs in it. B)

btw, for the technically unsavvy, LED stands for light-emitting diode.  that means current will only flow one way through them (you can't hook them up backwards), and they give off light when there's current flowing

almost forgot to mention, after 13 hours, the LEDs are still burning, albeit a bit dimmer... meaning < 138mA current draw... i'd like to see an incandescent bulb do that  :P

novell idea, can you take a picture once finished? :rolleyes:

(http://www.speakeasy.org/~ltphil/LEDunit.jpg)

there's a picture of it wired up to the batteries i've been running it on for almost 18 hours now... as you can see, it's still glowing, but not nearly as bright as it was when the batteries were fresh...  sorry the picture's so fuzzy, but it's the only digital camera i've got, and it was free.  abso-f*cking-lutely free.  :blink:

*looks for his NiMH charger*

the perfboard it's on now is perfectly sized to make four of the units, as you can see the solder pads are divided into quadrants, each of which fits one LED array quite nicely.  the LEDs and resistors cost me about $3, and the board was about $4... so that's a $16 expenditure to do all four turn signals... not too bad, imho.

LEDs are really cool. I have some 10mm red LEDs but i have no idea what to do with them.

how many of 'em do you have and how bright are they?

4, but i can buy more. 3000mcd i think, its mcd right?

:rolleyes: Nice....hope it works alright, the way you want it to, could you show us finished project pics, when finished?

ya, it's mcd (million candella, one candella being the brightness of a single-wick wax candle)... honestly though, i don't remember how bright a "bright" LED is considered, versus a normal LED...

as for project pics, ya i can post 'em but they're gonna be fuzzy, and also it'll be a while before i finish it, as i still have to buy the LEDs and resistors for the other three units, and i'm VERY strapped for cash.  i can just barely afford my DSL, car insurance, and lan parties.

At least he's got his priorities straight. :P

well the only reason car insurance is before lan parties is because i need the car insurance so i can drive to lan parties  ;)