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Subject: Re: [Homebrew_PCBs] Reproducing Unavailable Circuit Boards

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2005-09-22

On Thu, 22 Sep 2005 19:22:47 +0200, Tony <trossi@...> wrote:

> Hi all,
> Didn't see any discussion on this topic in past posts, so I thought
> I'd throw this out to the group...
> I am trying to reproduce a circuit board for a very old arcade game
> from 1975. Its an old style pitch and bat game, so the electronics
> are fairly simple, but the board is huge (approx 13x19") with about
> 100 TTL Logic chips and various resistors/capactors. Double
> sided... This board is no longer available and I have not been able
> to locate a board for quite some time... I was able to borrow a
> board from a fellow collector, but it is only on-loan. I also have
> the schematics...
> My question to the group: Does this sound like a resonable process
> to reproduce this board:
> 1) Remove all components from board
> 2) Scan in both sides (double sided board)
> 3) Touch up artwork and output to transfer paper
> 4) Transfer images to copper clad board
> 5) Etch, drill, populate...
> Is this the process most of you would follow to reproduce a board?
> Or am I missing an easier process? I actually thought about re-
> designing the board a little smaller, but I cannot afford the cost of
> an auto-routing software package to do a board of that size.
> Any thoughts or suggestions?
> Thanks!
> Tony


First, forget about auto-routing. It doesn't work.
Without putting WAY more effort into setting it up than it would take to
hand route a few boards that is.


I wonder if a fully manual method would not be easier in this case,
putting a piece of transparent paper over the board and drawing it...
scanning and touchup would work well with a software that supports layers,
like paint shop pro for example.

It sonds like a right nightmare to me, the whole affair. Desoldering all
that stuff, and then making sure it works after re-populating.

I haven't reproduced a PCB from the board itself, but i have reproduced
several layouts that i had as bitmap into files for my layout software,
using the import picture feature and working "over" it.

ST