The Process of Creating the Apple 1 Mimeo

click here to go to kit information page

component and
            trace placement

How Did I Do This Project?

This image will give you an idea of how I use the scan of an original to make sure that component placement and traces are as close to the original as possible.  The red overlay shows pad and trace placement as exported from my CAD program.  The black is the silk screen layer, also exported from my CAD program.  Any discrepancies can easily be seen when this CAD output is placed in photoshop over the photo of an actual Apple 1 board. I expect most of the layout of the finished board matches the original placement within 10 mills.  That is 1/100 of an inch.  There are some traces that are routed under chips that are best guesses based on experience.

Here is pre-production image showing the  PCB as seen in the CAD program.  The final production board has been tweaked and improved beyond what is shown here.

Check out my blog for a history of this project and continuing updates.

Check out this image of a pre-production version of the layout overlaid over an actual image of an Apple 1 (large file >1MB)

Note that there is some distortion in the Apple 1 image, that may cause less than perfect alignment in some areas.  This is particularly evident in the upper left corner.  The final production board has been tweaked and improved beyond what is shown here.

Follow this link for some info on parts and sources for the Apple 1


side by side
In order to give you an example of the results, here are two larger than life size images - the image on the left is that of an original Apple1, the image on the right is a Mimeo 1.  

One of the things I'm most proud of, is the attention to detail I put into the solder mask layer.  Note how the mask exposes some of the trace above "IRQ", but not above "KBD".  However there is just a nick cut out of the trace to the left of "KBD".    Just a sliver of the trace below "NO DMA" is also exposed.  I had to give the PCB manufacturer special instructions not to "fix" these areas.

I am also very satisfied how the lettering came out.  Recreating the font and placing the letters was very time consuming.  In many cases, I had to individually place letters in order to get spacing between them to look the same as the original.  The lettering that was etched in copper looks a little heavy in these magnified web images.  However they look fine when viewing an actual PCB.   I have frozen the artwork, and I'm not likely to change anything in future production runs..  In my experience, any improvement in one area can be offset by an unintended regression in an other.

Kit Builder Feedback

I received this feedback from the owner of an original Apple 1 and an Obtronix Apple 1 clone.  He bought a Mimeo kit as a learning tool for his teenage son, who was interested in computers.
Here more feedback from a person that at one time had several original Apple 1s in his possession.
more feedback from other folks
A few Mimeo owner's web pages and blog entries

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