X-ray board restoration and Altair 8800/Macintosh X-ray Was: Apple IIe X-Ray

[Grant Stockly]

>Well, if the board is just double sided (i.e. all tracks visible, except
>where they pass under components), you can generally trace tracks by eye
>and confirm with an ohmmeter. And if there are internal tracks, I think
>tracing those from an X-ray image wouldn't be exactly trivial.

Before you read the text below, am willing to help anyone out who has 
equipment they want to reproduce (as far as getting the x-ray goes)...but 
its not a fast and easy method.

It isn't easy, and I would advise against it.  If you have 4 layer product, 
TWO boards and are willing to throw one away, then it is cheap and easy.  I 
wouldn't have ever came out with www.altairkit.com without the guys at 
www.mhtest.com.  They will take your 2-3-4-etc layer board and generate 
production ready cad drawings.  A 2 layer board does not need to be 
destroyed, however a 4 layer board will need to be "planed" so that they 
can scan the inner layers.

Most 4 layer boards just have a VCC and GND power planes, so the top and 
bottom are the signals.  I still wouldn't use the x-ray to generate the cad 
artwork.  Been there...  ; )

Here are two shots of a Mac 512k motherboard.  You can see the difference.
This is what a 4 layer board CAN look like.  You can see the holes in the
middle layers where the through hole devices go through.

http://media.diywelder.com/images3/090605-512kRAM.jpg

http://media.diywelder.com/images3/090605-512kProcessor.jpg

Take a look at my website at www.altairkit.com and read the story link.  I 
first tried to duplicate the boards with x-ray, and even developed a way to 
do it (it just takes a lot of time).  The method involves scanning the back 
of the board as an image and combining it with the x-ray.  The grey traces 
will be on the top and the orange ones will be on the bottom.

X-ray of Altair 8800 CPU board:
http://www.stockly.com/images2/060119-Altair_8800_CPU_BD_Rev0-XRAY.jpg

The photo scan of the Altair 8800 CPU board:
http://www.stockly.com/images2/060119-Altair_8800_CPU_BD_Rev0_Back-Flipped-Cropped-Rotated.jpg

The x-ray / photo composite:
http://www.stockly.com/images2/060119-Altair_8800_CPU_BD_Rev0-Composite.jpg

Grant