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the first post should work but the 2 watt resistor needs to be a 68 ohm since you have the LEDs already soldered.
add some capacitors to the power supply just to be sure.
the capacitor on the 555 C! can be changed to a different value for a different flash rate.
,1 = 95hz .005 high and .005 low on pin 3(flash rate on and off)
1uf = 9.5hz .05 on .05 off
10uf = .95hz .5 on .5 off **broken link removed**
if you want to use transistors instead of the ULN2804, I added a sample. pretty sure it should work. test it BEFORE using. use a amp meter to measure the current draw at the transistor base. the 4017 will output only a min amount of current (without looking at data sheet I think its 20ma).
Maybe someone with more savy can critique the schematic. Nobodies perfect. Well the last time we had someone perfect he died some 2000 years ago
they arent soldered its just glued right now. If i need to i guess i could change it around but it would be challenging because i dont know how much more bending the anode and cathode can take. so when this is all said and done, this will make rows of LEDs resemble something remotely similar to a rotating light? Also i dont know the limit of LEDs. I know that they wont burn out without insane use, but how long can they withstand going on and off every .005 of a second? the light, when its used, will be on for maybe an hour to an hour and a half if it is used. so thats...720,000 times on per hour. could they tolerate that? i might just have to go with 2.5µF area capacitor. I mean, im open to anything i just need more experienced opinions.
I would go with the 10uf capacitor. 1/2 second on is really not very long. maybe even use a larger capacitor for the LEDs to light up say 1 second on.
seeing how you have the LEDs already glued, just go with what you have. it will work.
but remember that this needs to simulate a rotating light. at a half second interbal, it would not be very rotate-like, but this does solve one of my other problems because i want to make LED blocks that turn on in sequence at about every half second so this plan works pretty well. When i said 2.5µF earlier i meant to say 7.5, but now that i think of it i think 5 should do the trick. Now while i have your all's attention, maybe you could help me with blocks too? I dont know how to wire the circuit properly. and do they have such things as "dual output blinkers" that alternate which is on and off equally? that would be best for the blocks
What do you mean by BLOCKS?
just wire up the circuit as the schematic shows and connect your LEDs (wired as you pictured in parallel) to the collector of the transistor for that output. The 4017 increments each clock pulse so if you have a clock pulse say every second then the LEDs will light up in sequence every second. If its too fast then change the pot adjustment and/or the capacitor value.
im working on that too im just saying i have another project. i know matrices are extremely dificult thats why im not making one. all im doing is making blocks that are either all on, or all off.
A matrix is not real hard to do its just a whole other animal.
a simple 5x5 matrix or a bunch of LEDs mounted like a 7 segment display either way they are doable.
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