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Subject: Re: [Homebrew_PCBs] RE : Design rules for hobbyist PCBs...

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2006-05-05

On Fri, 05 May 2006 01:10:27 +0200, Robert Hedan
<robert.hedan@...> wrote:

> Ok, I have a question about this page:
>
> http://www.instructables.com/ex/i/532834782C781029BC6B001143E7E506/
>
>
> I've never done this, been mainly using microprocessors so far.
>
>
> How does it 'start'? Which LED blinks first? Is it a sort of lottery,
>
> depending on which capacitor gets charged first? I figure we are
> assuming
>
> the capacitors won't be perfectly identical (due to tolerance range).
>
>
> Both 'sides' of the circuit are identical, so I would assume matched
>
> blinking rates (50% per side). It's the 'first step' that always
> bothered
>
> me with these kind of circuits, what happened RIGHT after you pushed ON?
>
>
> The flip-flop stuff is another thing that I have serious trouble
>
> understanding.
>
>
> Robert


The books usually say "imbalances in components" i think.
If you believe in god, why not give the guy some credit?

I had to force a default position to go on all the time in a similar
circuit once, it wasn't as easy as one would have hoped. Using larger caps
in one place did not work. But it was different to your multivibrator, i
think here they would.

ST