[rescue] Sun 3/80 Schematics

[Arno Kletzander]

Bill Dorsey <dorsey at lila.com> wrote:
> Not really possible for the 3/80 unless schematics turn up or unless someone
has an extra 3/80
> which can be sacrificed at the altar of reverse engineering.  There are
places which will take a
> depopulated board, scan it, and create schematics from the scan.  In the
case of multilayer boards,
> they will strip each layer off and scan it repeatedly until they have all
layers.  Not sure about the
> costs as I have never had it done, but I know it exists as a service.

I had a look at a few photos of the board in question and going from that, it
probably is a multilayer. Nevertheless it might not be necessary to go that
destructive, as metal traces stand out quite well against the PCB substrate
(and even against a ground plane!) in an x-ray image. Biggest problem might be
any unsocketed, metal capped chips. (I have taken x-rays of PCBs for quality
control of solder joints, inspection of reject parts and various development
tasks at times, with a Nicolet NXR series machine.)
X-Y table movement range and magnification would likely be sufficient for such
an endeavour, especially as series of images can be stitched together to cover
a larger area; images from a machine without sophisticated image processing do
suffer from a rather strong pincushion-like effect that is caused by the
projection properties of a point source, which might however be possible to
alleviate even after the fact with suitable software.

Good luck with your effort,

Arno // DO4NAK