By Now, im sure you guys know about LEDs and how they work. A typical LED's forward Voltage is about 2.3V and base forward current is usually 20mA (.020 Amps). These numbers can change drastically as there are different LED conductors and sizes and such. from a dim diffused panel LED to a single 1 Watt wide angle (really bright) White LED. A 1 Watt LED works at one watt, (Watts is Volts * Amps) so if you have a 60 Watt Light Bulb in a socket in your home. You know that the wall voltage is about 120VAC, so to figure out the current draw on the Incandescent bulb, you want to know "What value times 120 will give you 60?" and the answer is 1/2 or .5 so if the bulb is 60 watts and the voltage is 120V, the current draw will be about .5A. We use this to figure out values for fuses and conductor sizes too.


Getting back to the LED's, we can wire them up to a battery with a resistor and "Yeay! it lights up! whoo hoo!!!!

...Now can we make them strobe? Hmmm......


This circuit Will make a simple flasher for a single LED. To add more LED's the circuit can be modified later. The theory behind this circuit is easy. there are 2 resistors and a capacitor to adjust the timing cycle. a resistor is a device to resist current, and a capactor is like a bucket with a hole in the bottom. you can fill the bucket up fast, and the water will slowly drain out. (unless you flip it upside down, this can be done with a cap as well). when you give this circuit power, the capactitor get a small amount of current through the resistors, and it slowly fills up. pin 7 detects when the voltage reaches a certain voltage peak determined by the resistors and when it does, the capacitor is discharged through pins 6 and 2, when the voltage drops, it switches back and starts to fill again and repeats the cycle over and over again. When the cap is discharged, the timer is triggered on, and when when the threshold voltage is low, it switches back off. By doing this, we get a frequency (how many times per second) and a Duty Cycle (is the on pulse longer than the off pulse? or the off pulse longer than the on pulse? or maybe it's equal?). The way this circuit is written, if you adjust the variable resistor to 1K, it will flash about 3 times per second. as you decrease the resistance of R1, it will flash faster, because by lowering the resistance, your opening up the faucet into the capacitor.


The NE555 is a tiny 8 legged thing called a timer. you can buy them at radio shack, or order them online by the million. (or call me up and ill hook you up)




It also makes no difference what color the LED is, this circuit should be ok with most of them. Just be sure that the anode faces the positive side (or away from the negative side) as LEDs have polarity.) putting them in backward wont burn them out, they just wont light up.

No comments so far, i hope that is a sign that i explained it well enough so you guys can understand it

How much for some of those timers and some LED's?

do you want just the timer? or you want it assembled? (obviously with the LED not soldered on the board)

There is a way to flash more than 1 LED as well, it is an add on to the circuit i have here.

LED's prices vary by color, But Red and White are about .35 each, these are High brightness and wide viewing angle LED's, I also have diffused (Meaning the lens is the same color as the LED) narrow angle, 3mm red, 5mm red, 3mm white, 10mm white, i have lots of different sizes and shapes.

My stock may be limited because i hopefully have an install to do for J kellz coming up soon.

pm me or AIM:

Metalfan036

and if you want to see my electronics page, go here:

Http://www.myspace.com/CustomAutoElectronics

i will have a surprise for everyone within the next two weeks or so hopefully, done by my boy josh here

that's pretty cool. You have an electronics degree?

Ill do my best, and no, i don't have a degree, but expierience weights more than book smarts (most of it I learned from books and tinkering, so luckily I have both)

got the message, almost waited at dunkin, but i got it before i left.

so Jkellz, Ill talk to you on tuesday. I get out of work at 3:30PM so maybe we can meet up. I had some crap on my computer so i wiped it and reinstalled everything. I put all my electronic simulation programs in it as well, so i can show you some of the circuits i have in mind specifically for your car.

works for me man. like i said im around all day tuesday so hopefully we can meet up and get the ball rolling on the project. any money you need to get started with all this let me know, i got it covered

Thursday

4:00pm

Dunkin lot near cinemas and shell station

aiiiiight!!!!

lol

got it ill be there man

this is a little off topic, 'but those 4x8 sheet mirrors are expensive! if i had a truck i would pick them up too lol

wooooo tomorrow

Nice to meet you in person Kellz.

I went home last night and went over what we talked about and I ran a simulation on the computer with MultiSim 8. The circuit works on the computer just fine, i only had to change the 7474 flip flop with 2 NAND gates (operates the same way). Logic probes and oscilloscopes say everything is good to go.

Now im working on getting those blue ones, (which i have been told are not really on sale and could cost over a dollar a piece) and building the prototype of the circuit on a temporary board. From there we can start the build.

The only part i need to find is the heatsink size for the MOSFETs, if they dont get too hot, i can screw them to the inside of that aluminum box (hopefully) with thermal paste. Or i may need to find little heatsinks that fit in the box. I may just add a tiny fan in there to (so i can use slightly smaller heatsinks in effort to make everything fit better.)

Im definitely excited about this project and i will have results soon!

aight man sounds good to me. def good meeting you too, except half the time i had no idea what you were drawing or were talking about, but by the end i understood alot more than i ever thought i would. this project is gonna come out great. i cant wait to see the prototype

Ok, I have a decent prototype built, but it's only for the signal level stuff. I know the Driver stage and LED clusters will work. So i have the first experimental prototype built on a Solderless breadboard for testing. I have the frequencies in the right spot, i just have to hook it up to an oscilloscope to set the duty cycles to 50%.

I know i keep promising pics, but they really are coming soon. lol

Every time i want to take a pic, i think "maybe i should change this first..." and one thing leads to another and then im stuck making excuses to a forum of why there are no pics LOL

hey no worries man i know ur workin on it and that its not an overnight type project

Do you want this to be a surprise kinda thing or should we make it it's own thread in the electronics section. doesn't matter to me. just wondering. lol

i think we should do a seperate thread with a step by step and before and after type thing

if i am correct that 555 is staic sensitive as well don't hold me to it but i am almost positive when were talking about the 555 in class at school last year it was a static sensitive device if i am correct you may just wanna toss in a little warning about that just my 2 cents

Hmmm, well, yes, i suppose with the correct amount of high voltage static charge you may be able to damage this chip, but it is on the lower end of the static sensitive scale. I have used 555 IC's for about 10 Years and I have never damaged one on account of Static Discharge, and i usually dont have a ESD strap on while i experiment with this stuff.

but yes, you may want to ground yourself out just to be sure before you start messin with it. It sould suck to install it and have it not work.

by the waym the resistor values are variable too, you can change them to get whatever speed ytou want.

Thanks, i didn't even think to mention that.



however, the 7555 is the CMOS version of a 555, and these are very static sensitive as most CMOS chips are. so be careful.

Kellz,

I actually just learned an important concept with LED's that i didn't know before. If you set up a signal at a set frequency and about a 10% Duty cycle, Some LED's that take 40mA to stay on solid can be pulsed at 100mA+, this makes the LED a lot brighter. I was unaware of this before. Im looking into whether the same holds true for all LED's (i would imagine that it would, just the concept, not the exact specs)

That being said, now not only can i dim the LED's down, I can also make them brighter without damaging the Junction with overdraw!


btw, we still need some enclosures for your Clusters, so, look around and let me know what you find. Im lookin around here too. Ill let you know if i get somethin!!!!

yeah ive been looking for some too. worst case i go to home depot, and try to do some custom plastic building

Alright Kellz, here's the update.


On the way are more Blue LED's coming in the mail. Haven't recieved the ones from germany Yet, but they should be here soon.

Circuit it built, im just lookin for ways to make the timing more exact. once i get it, im soldering it on a circuit board so we can set it up with some basic clusrs to check it out.

Keep lookin for stuff to make those encloures out of, because i don't have crap as far as that goes.


It's comin bro, wont be long now

After a week and a half, I have recieved those LED samples from Germany, They are OSRAM High-Flux LED's which are a considerably Great quality. I lit a few up and im pleased with the color and brightness. They use less current than the Red Led's, but i may have to Dim the reds just a hair to match the blue ones. The lenses are a little bigger than the reds, but i dont think that will matter much. (red = 3mm, Blue = 5mm) Ill have to light a couple up for ya when i see you.

I picked up my ball joint last night for the car. I have a tie rod end too, so, if you want i can head down there wednesday to replace that at your spot. Its not pressed in, it has bolts so it shouldn't be a hassle anyways...

Let me know, either Wed or Fri like you said.

aight sounds good. ill let you know tonight what day is better for me so you can do the tie rod

Yeah, ah, I left my phone at a friends house, so, im probably going to pick it up after work. If your trying to get a hold of me, im at work, and you can get me on here

i gotta work til nine tonight. i switched some shifts around to get this weekend off to go snowboarding so i have to work every night til fri so i can leave for maine sat morning

ok, no big deal.

Does that include Friday?

Still waiting for LED pics

.......damn...