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hardware/keyboard-sol/README.md

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+# SOL keyboard
+
+This keyboard replicate the keyboard on the SOL-20.
+
+The keyboard is designed using KiCad in order to be the most useful for anybody
+wishing to modify the keyboard for more specific uses, or to add to the project.
+
+The keyset for the SOL-20 keyboard consists of the Unified Keyboard Project
+classic ASCII keyset, with a special SOL-20 add-on keyset.
+
+## Differences from the original include:
+
+1. The original keyboard is a capacitive keyboard. This keyboard uses standard
+   switches (either Cherry or Futaba). The Futaba keys approach the original
+   feel, but there is a difference.
+   
+1. The original keycaps have an 11 degree angled stem. It may be possible to
+   find such keycaps, or to create an 11-degree adapter, but I was unable to do
+   so, so this keyboard was tested with straight keycaps. I have tried both, and
+   do not find a difference in typing comfort or speed, althought there is an
+   aesthetic difference. There is s tiny bit of space between keys using
+   straight keycaps, so an 11 degree adapter may not require any change to the
+   layout.