Some summer is almost here and once I get a job and finish my computer I've been working on for the past year (i have absolutely no money), I'm going to start my first case mod. I have my theme and everything all planned out. It's going to be a zombie themed build and I have how it will look drawn out on paper.

One of my ideas for it (if any of you have read The Zombie Survival Guide) is have a fan controller with just one knob that i would put into a 3.5" drive bay. Next to the knob, there would be 4 LEDs, green, then yellow, orange, red, from left to right. Under the green one, it would say "Class 1" then under the yellow, "Class 2" etc. Then when you increased the fan speed, the lights would light up down the line, so as low power, the green one would b lit, at max, the red one would be lit.

My problem: I am terrible with electrical stuff. My knowledge goes as far as knowing how to solder from this tech class i took in jr. high. If anyone could help me out with this, it would be GREATLY appreciated.

You come to the right place, Twizted can help you out with that one. I sent him a link so he should reply shortly

Well, there are a couple differant ways this could be approched... but as far as I know there are not comercially available options for this and it would not be a simple circuit to build one... atleast I dont think it would but then I just read this and have not had time to research it.. But alas... I am not a teacher by any stretch of the imagination as I suck at explaining anything..

I have in the past made and sold high load fan controller and it is quite possible that a indicator circuit could be built into one of them although I would have to do some R&D into this.. If you were interested in this let me know (PM or IM)

Do you really think it would be that hard to mod an existing fan controller or something? Otherwise, I have an X-cruiser case that has a circular meter that shows the fan speed, do you think i could find on of those and change the labels?

Yeah you could but its not what you first envisioned. Simpler? why not just have 4 micro switches to turn on the LEDs instead of a variable to turn on the leds.

Quote: Originally Posted by Lokie Yeah you could but its not what you first envisioned. Simpler? why not just have 4 micro switches to turn on the LEDs instead of a variable to turn on the leds.

I do remember a circuit for what he is taking about, But for the life of me I cant remember where it is. It was on a site called 7voltmod and it used diodes, and resistors along with a switch and LEDs (doing a google search yields nothing that Im looking for).

Found it!
Switched Diodes - The Diobus ©

Thats what your looking for.

you could use a LM339 quad comparator and a voltage divider.
Simple Voltage Detector Electronic Circuit Project
this link uses 4 pots but if you want to use 4 or five fixed resistors instead you would just need to do a little simple math with ohm's law Voltage divider - Wikipedia, the free encyclopedia normally i'd tell you more and duplicate it on a breadboard for you but i have a papers to write. Nerdz or Twizted will probably tell you more if you are interested in this route. its less than $10 at radioshack

Yeaaaaaah....... as I said before, my level of electrical stuff is basically zero. I mean, if I had all the parts and knew where to put them, I could do it, but I cannot understand those schematics for the life of me.

It would be MUCH appreciated if someone could put either this:
Switched Diodes - The Diobus ©
or this:
Simple Voltage Detector Electronic Circuit Project

in EXTREMELY simple terms.

Thanks for those guide! =)