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The WOMBAT Morse keyboard


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WOMBAT, in "Hacker's Dictionary", means "Waste Of Money, Brains And Time". This obviously refers to corporate-level pointless projects, not to our own toy projects that happen to be impractical. In any case, the acronym sounds good and baptized my jerry-rigged Morse keyboard.

Figure 1: The WOMBAT keyboard, completed

In a sense I set out to make the most ugly and kludgy keyboard as possible. Took a 6x4 switch tester, soldered 48 leads instead of ten because I didn't want to wait for the diodes to start "doing something", and held everything together with hot glue because the leads extracted from an Ethernet cable are quite brittle, particularly near the solder.

Figure 2: WOMBAT keyboard wiring, with diodes in a separate PCB (bad idea)

The keycaps are leftovers from nice SA sets that were installed in other keyboards. Lots of mismatches but at least the keycaps themselves are the nicest.

Of course this is a testbed to get acquainted with keyboard building, and the next 'Wombat', if I ever build one, will be based on a nice PCB with SMD diodes, nice case, etc.

Figure 3: Some keycaps that match the special characters but are not as nice as SA ones

The 'plate' is an acrylical switch tester, which came with 24 assorted Kailh switches. I have tried to move the 'best' switches to the Morse-related keys, which are (or rather would be) used the most. The most important keys were placed at corners, the Morse keying buttons try to be as ergonomic as possible.

Figure 4: Mix of SA and low-profile keycaps, seen from the side

The controller is a Pro Micro, an Arduino-like board that has a USB-capable chip (ATmega32u4). The firmware is based on QMK project, just started off from a 4x4 barebones target and added things incrementally. Provided the controller hardware is supported, QMK is a breeze to use. It was a matter of minutes to put it to work. I was inclined to use TMK since it had worked well for me in my AT-USB converters, but QMK is much more practival, at least when dealing with keyboards instead of converters.

Part of the WOMBAT allure of this project is trying to make a full-featured keyboard out of just 24 keys. Having played a bit with a 40% keyboard, I don't really believe keyboards smaller than 60% are practical. But we can try, right? :) My implementation can be found here. Naturally, I won't make a push request back to QMK.

In spite of being a gimmick, I think I have achieved a 'complete' keyboard with as few 'chords' (combinations of 3, 4 or more keys) as possible. These are the highlights:

And here is a demonstration: