Poll

So, which old keyboard should I be using.

The generic Apple ][ clone numeric keypad
0 (0%)
The old Compet keyboard
0 (0%)

Total Members Voted: 0

Voting closed: May 12, 2014, 09:06:16 AM

Author Topic: Keboard building.  (Read 2515 times)

SeanB

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Keboard building.
« on: May 07, 2014, 09:06:16 AM »
So, I want to add a numeric keyboard to my PC for entering numbers.

I can buy a numeric USB keypad which does 0-9, decimal, enter and basic math functions ( and I did) for $3, but it does not have what I want, which is a comma for delimiting.

So I bought the cheapest USB keyboard around ( $3 Astrum OHL one) and took it apart, then spent a little time reverse engineering the keyboard matrix to figure out the required pins. Took the COB and cleaned the graphite screen that was used to connect to the screen printed mylar keyboard, and soldered the required 11 wires to it. To clean the pads I used some scouring powder on a cloth and gentle rubbing, followed by tinning the bright copper traces left behind. Then soldered the wires from the closest multicore cable I could find, which was salvaged from a Tektronix Phaser 340 power supply, and now i am looking at the keyboards I have around to use.

1 - A never used Apple ][ numeric keyboard in a housing, which has been sitting around since the 1990's and never used but still working.

2 A somewhat used reed switch keyboard from an old Compet calculator, which I took apart when I was young, and which was given to me. Kept that keyboard ( with mechanical interlock to prevent multiple keypresses) for decades in a box. Still have the 4004 processor card as well for it. Attached is the COB, and the 2 keyboards for comparison.

So, a poll to choose the keyboard to use. After it closes I will probably have to either fit the USB interface in the box, or buy a small project box and cut a hole in it to fit a keyboard. In any case I will have a keyboard.

birrbert

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Re: Keboard building.
« Reply #1 on: May 07, 2014, 12:06:47 PM »
Both!? ;D
"Dubito ergo cogito, cogito ergo sum." Descartes

SeanB

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Re: Keboard building.
« Reply #2 on: May 07, 2014, 12:21:09 PM »
Not likely, then I might as well stick with the existing Microsoft keyboard I have. I wanted something a little smaller for using one handed. At least you can have multiple USB keyboards, and they all will work together as well.

MJLorton

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Re: Keboard building.
« Reply #3 on: May 20, 2014, 12:20:09 PM »
I would have thought the tactile feel of the Apple ][ keyboard would be the best....so that would be my choice.
Nice to see the  reed switch keyboard...I remember playing with a keyboard on an old CRT calculator that had a  mechanical interlock...now that was a little while back!
Play, discover, learn and enjoy! (and don't be scared to make mistakes along the way!)

SeanB

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Re: Keboard building.
« Reply #4 on: May 20, 2014, 01:44:21 PM »
Apple clone keyboard, basically the same as any Cherry switch clone. Has the advantage of a nice slimline case around it, and I probably could shoehorn everything into the spare space there. Other one I will have to make a case for, which I have done before, though it did not look pretty. Will have to look at A1 next time I am there for a cheap case to cut down.