IQ Keyer
https://sites.google.com/site/iqkeyerproject/home/assembly-manual
K3NG CW Keyer
https://github.com/k3ng/k3ng_cw_keyer/wiki
https://www.hamshop.cz/open-cw-keyer-c27/open-cw-keyer-i196/
K3NG CW Keyer by ZS2EZ
http://www.zs2ez.co.za/k3ng-keyer.html
CW Keyer with Arduino Nano by SV5FRI
http://www.sv5fri.eu/?p=1611149
Nano Keyer (Shop DE)
https://nanokeyer.wordpress.com/enclosure/
Arduino CW Keyer
https://blog.radioartisan.com/arduino-cw-keyer/
https://kf4bzt.wordpress.com/2015/08/06/arduino-cw-keyer-project/
https://ac0c.com/main/page_homebrew_a_few_good_cw_keyers.html
CW Keyer Kits
http://www.hamcrafters2.com/K16keyer.html
Capacitive CW Touch Circuits
https://m0ukd.com/homebrew/capacitive-cw-touch-key-circuits/
Ebay Shop
https://www.ebay.co.uk/itm/automatic-CW-key-with-memory-MORSE-code-keyer-/332202458123
Shop UK
http://www.g4zpy.go-plus.net/table1.htm