Fader (in/out) fully adjustable built with much thanks to these helpful chaps on Bit-Tech http://www.insancen.co.uk/random/led_fader.jpg
Forget the fade on the second circuit I'll just forget that. Ok here is the deal I have found a small set of battery operated LED Christmas lights that will do the trick for the blinking second circuit the only question I have is how do you adjust from 2 C batteries to a 9v .. I think its just a resistor issue??????? which leads me into my next question, Can you link more than one resistor to get the same result as one? the Radio shack here only carries 1K, 5.6K, 10K, 22K resistors so can I chain the 5.6K and 10K to get a resistance of 15.6K? (they also don't carry a 68ohm resister) I got another LED to put in place of the 4 you suggested I use its a Jumbo super bright 5000mcd, rated 2.4V, 20mA Absolute maximum ratings Forward current (If): 40mA max Forward voltage (Vf): 5vDC max Reverse voltage: 6vDC Power dissipation: 100mW Electro-optical characteristics Forward voltage: 2.4v ± .03v peak emission wavelength: 660nm luminous intensity: 5000mcd (typ. at 20mA) Does that mean I need to replace the 68 ohm resistor with a 100ohm/ 1/2w resistor and just leave the rest of the circuit the same?(on another site I got a 330ohm or 390ohm with a power rating of 0.22w) I've never understood the real difference between a C battery and an AA battery they are both 1.5v.
More charge stored in the C battery. For example lets say an AA battery is rated at 1,000 mA hours and the C is rated at 2,000mA hours and both of them are powering a lamp which is rated at 1 amp. In roughly 1 hour the AA battery would have been exhausted but the C battery can go for a further hour.
use a voltage regulator (a zener diode) to regulate the voltage from the 9volt battery down to 1.5 volts for your string of leds. resistors add in different ways if they are in series or parallel... click the following link for more info on: http://metku.net/index.html?sect=view&n=1&path=mods/sahkooppi/index_eng#vastus you have a led that needs an average of 20mA and you have a 9v source. therefore, V=IR => V/I=R => 9/.02 = 450ohm resistor. now, it says it has a threshold of 40mA, so if you provide more current (a smaller resistor) it will get brighter, but have a greater chance of burning out quicker. if you provide less current (a bigger resistor) then it wouldn't be as bright but would last longer. as far as the power rating of the resistor, P=V*I = .02*9 = .18 watts. a 1/4 watt resistor will be fine assuming you use the 450 ohm resistor to give you 20mA of current.
Ok I've gotten the C to 9V conversion out of the way with little effort now all I have to get done is the fading circuit with the large LED and the one thing preventing that is the fact I need a 15K resistor I'll attempt to red up on it some more if I can find anything more on it. Thanks for all the help I almost have everything I need to get all this done I will post pics when I get all of this done I hope it turns out good.
450ohm = Dim LED 330ohm = slightly less dim LED considering it's Halloween tonight and I have to work today I'm not going to be able to get a smaller resistor so I'm just going to go with the blinking led strand I have. I appreciate everyones help and I will probably come back and finish this some time in the near future.
Not quite, with the fade up/down circuit. The 15k fade-up resistor always drops a few volts (IR, where I is (base current + charge current) so maybe 2V minimum with most small transistors as gain is usually well over 100, then the transistor Vbe is 0.7V, so LED chain sees about 6.3V max. If you've only those two resistors, try putting them in parallel for 190R, or leave them out, the LEDs have only got to last a few hours.
I was in the last Minute dash to get this all to work and as I was using my dremel to carve out a spot for my 9v and Bam! shredded wires I was in too big of a hurry and wasn't careful enough. My Whole project gone in 2 seconds flat. Oh well I think I will just try to finish it after this Halloween and use it next year. I can probably make it better when I'm not under such a tight deadline. I will most likely need more Help but for right now I'll put this on hold for a few days. Thanks guys you've been a big help.
Put a 555 timer in this please someone. It does the exact same thing as the original circuit, just with less components. I want the 555 to switch the LED's on and off instead of having a manual switch in there. http://www.youtube.com/watch?v=0VTOSMMF2Fk
