Results from survey...

Mike Morris morris at COGENT.NET
Mon Nov 16 18:58:53 EST 1998


I'm posting this just in case anybody seriously wants to
do something like this.  It is possible - if somebody has
access to a scanner, and a copy of Autocad, and the
knowledge/experience to run it...

At 01:24 PM 11/16/98 , you wrote:
>By the way, there was some interest in reproducing circuit boards.  In
>speaking with an lawyer, an EXACT reproduction of the circuit board is
>indeed a violation of copywrite laws.  However, you could make changes
>to the component placement and/or changes to the actual 'artwork' and
>sell it within the law.  An interesting thought.  There have been times
>that I wish I had the ability to 'rebuild' a circuit board using moden
>components.  Perhaps many of you have seen boards that were build by
>someone with poor soldering skills?  Boards with burns and lifted
>traces...

I once saw a PC board that had been "reproduced" - it was
for a Palomar RBC repeater controller (company now defunct).
The person had:
1) carefully unsoldered all the components
2) xeroxed the board - both sides - (so he'd have a image
    of the white silk-screened lettering to work from later)
3) spray-painted the board with dull black paint
4) buffed it with fine steel wool to reveal the copper
5) scanned it into a graphics program (I forget which
    one he used - I _think_ it was Autocad)
6) touched up the places where traces had been
    damaged during unsoldering
7) applied the corrective mods - there were a couple of
    etch cuts and jumpers on the original board
    along with some additional power bypass capacitors
8) added component identifiers into the etch - the idea
    was to eliminate the need for the silk screen by
    adding the "D1", C1", R22", etc into the copper.
    He also added polarity indicators for the diodes
    and capacitors
9 Repeat for the other side of the board
10) added a few things that were forgotten in the original
    board - like pin numbers to the connectors
11) adding a "proto board area" into some extra space
     on one corner of the board - un-drilled in the final,
     could be drilled if ever needed

I think that step 7 or 8 alone would take care of any
copyright problems.  If not, step 11 would.

He then had the program spit out a Gerber plot file and
sent it to a prototyping circuit board house.  There are
several of these around the USA, and they are not cheap.
They cater to engineering houses that need a half-dozen
boards to test a new design before full production.
They bill by square inch and number of copper layers
(some of the boards can do multi-layer) and by drilled
holes.  Some can also do silk screening, but it is generally
not done on prototype boards.  They advertise in the
engineering magazines like EDN, Circuit Cellar, etc.

For example, a while back a friend had a bunch of 4.5"x 6"
double sided boards made for a orphaned repeater controller.
They had a 22 pins-on-a-side edge connector, and a dozen
or so 16-pin ICs.  25 of these boards cost about $35-40 _each_.
Yes, not cheap, but there was no other way to do it.

Note that the final boards did not have the proto area drilled
(they charge by the hole) nor did it have gold tips on the
22/44 connector - that cost was absolutely prohibitive.

Mike Morris  WA6ILQ
mike at morris.com (preferred address)

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