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TOUCH KEYER SERIAL PORT INTERFACE

The Circuit Board Art Work     The Schematic

(this is really an overview about making back yard circuit boards)

*** News Flash! ***

I have now started to use a different light weight glossy photo paper to transfer the toner mirror image to copper. It's very light weight at 120 g/sm and glossy on both sides.

Also, it's A4 in size at 216mm x 279mm (8" x 11")  and made by Hewlett-Packard, Product No. CG988A.  *** THIS IS THE PAPER TO USE !!! ***

It's like glossy thin magazine paper. Hewlett-Packard call it "Presentation Paper".

A simple interface circuit knocked up with MS Paint and copied to glossy photo paper in a 2 step process. This time I tried something a little bit different. First, I

imported a reverse "mirror" image .BMP file into MS Word as usual. It is then scaled to the correct size. For this project it's 3.75cm x 4.68cm. I printed the image to a 

standard piece of A4 paper. The A4 paper image is then put on the printer/copier machine and a piece of A4 glossy photo paper is put in the printer/copier paper tray

and a "copy" is selected rather then printing the digital image from the computer straight to glossy photo paper. This technique gives easier control of the toner "lighter/darker"

adjustment which I set to the darkest setting.

(It must be laser toner printing. Ink jet printing will not work!)

 

This is the opposite side of the glossy photo paper which had the art work toner image on it. Very very carefully peeling the smooth backing off the back side of the

glossy photo paper and exposing the coarse  porous paper. This helps to let the hot water soak in from the back side of the paper and release the toner image from

the glossy side of the photo paper.

 

After running the glossy photo paper and copper through the laminator 10 - 12 times, then setting it in hot water for 10 - 15 minutes, the glossy photo paper will release

from the toner image and float away. This is what is left. a 99 percent transfer of toner image.

 

The art work toner image transferred to copper and the copper circuit board cut and filed to size.

 

The interface circuit board after the Ammonium Persulphate etching has removed all the unprotected copper.

 

The interface circuit board after etching and with the holes drilled for the DB9 connector, 3.5mm audio socket, 6 pin optocoupler, LED and resistors.

 

A top view of the etched and drilled circuit board.

 

The completed interface board.

 

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