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Random LED flasher

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Can anyone help me build a random 2-LED flasher?? I've seen projects for flashing LED's but they all have fixed intervals... what I'm looking for is a circuit that would flash 2 LED's at the same time then flashes again with indefinite intervals... around 1 - 2 seconds intervals would be fine but again, random... your help will be greatly appreciated...
 
Maybe not as complicated as you are looking for... but, I once bought a bunch of flashing red LEDs cheap ($5/100). They seem to flash ar different frequencies. I've been using 5 wired in parallel to discharge a small rechargable lithium battery I have been playing with for a couple of weeks (using LEDs as solar cells). Get pretty interesting, and apparently random patterns.

There are are dozens of 2 transistor circuits to flash LEDs on the web, will take a look later, might have on on my HD to post. But if you put together 2 identical circuits, they will flash at slightly different frequencies due to component tolerances (caps and resistors).

Have seen, and likely have a copy, of a circuit using a 4xxx CMOS chip, that flashes randomly. Just seemed like a lot of pins for something I could do with an 8-pin AVR chip.
 
I do not know of any LEDs that blink randomly. My LEDs have a blink rate or a blink pattern.

Is this an experiment? Do you have an application where thousands will be used?
 
What you want is a pseudo random number generator. Adapt something like this to drive the LEDs:
**broken link removed**
 
You can build a simple psuedo random generator with some flip flops or shift register ICs. For example, my old Forrest Mims "Engineers Notebook" has a simple pseudo-random generator circuit that uses a pair of 4021 logic ICs fed by a simple RC clock. There are many variants using shift registers of all kinds. Here is one (scroll down a ways):
**broken link removed**
 
Use white noise and a comparator set at a certain level.
 
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