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

From: Robert Hedan <robert.hedan@...>
Date: 2006-05-05

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
:)



> -----Message d'origine-----
> De : Homebrew_PCBs@yahoogroups.com
> [mailto:Homebrew_PCBs@yahoogroups.com] De la part de Bill Westfield
> Envoyé : mai 4 2006 18:37
> À : Homebrew_PCBs@yahoogroups.com
> Objet : [Homebrew_PCBs] Design rules for hobbyist PCBs...
>
>
> FWIW, I've published some advice/opinions and tutorial
> information on how to design your PCBs so that they're more
> easilly fabricated in a homebrew/hobbyist context. The
> tutorial is based on EAGLE, but the principles should apply
> to other CAD packages as well.
>
> http://www.instructables.com/ex/i/E8C98D522C771029BC6B001143E7E506/
>
> BillW
>