Hello - electronics n00b here. I'm trying to build an LED chaser to go on a costume I'm making. The LEDs need to do a single chase, then stay off for about 5-6 seconds, then do another.
Soooo, to change the duty cycle so it was off more than on, I put a N4148 diode in parallel with R2 on the 555 circuit. I'm using the 555 astable diagram from
555 and 556 Timer Circuits
with a 47uf decoupling capacitor and C1 as 10uf, plus the 0.01uf control.
This worked fine with a single LED - it came on for a second, then stayed off for five seconds.
But when I hooked it up to the 4017 using this diagram (
**broken link removed**) and 270R resistors, all the LEDs came on dimly, and then each one would brighten in turn with 5 seconds between each LED. In addition the dim illumination of all the LEDs wasn't consistent, it varied.
I'm guessing that the 555 is generating a signal every five seconds, but instead of that triggering a cascade which was what I was after, it's just messaging the 4017 to switch the next output to high.
So what do I need to do to convert that signal every five seconds into a cascade of pulses to the chaser? And how can I make sure the LEDs stay off between chases, as opposed to being slightly lit?
Thanks in advance for your help - I've been on so many websites to try and figure out how to make this circuit, and now that it doesn't work I am at my wit's end!