This page is just a reminder for me, so i can find the commands i need from everywhere in the world...  ;-) But it can be helpful ...

I've built a K3NG keyer with a small Arduino Pro mini board. I needed minimal functions :
- 3 memories
- a small speaker for the monitor.
- no speed pot.
- no USB interface.
- sleep mode after 1 minute.
- all settings are done in command mode with the paddles.

To be used in the field, the keyer is powered with a 3.7V battery. When in operating mode, the keyer consumes about 4mA, in sleep mode after 1 minutes : 0.1 uA ! No power switch is needed.

The author's Web page :
The software can be downloaded here :
The K3NG keyer Wiki is available here :


File Keyer_features_and_options (only this lines were uncommented)

File Keyer_settings (Changed only this line)
#define go_to_sleep_inactivity_time 1
#define analog_buttons_number_of_buttons 4


Enter in command mode by pressing the command button
Exit command mode with X command or press the command button

Px - program memory x (1 to 12), or press memory button after command button
Yxxxx - change memory repeat delay to xxxx ms
REPEAT press the memory button and keep it pressed then touch a paddle.
ERASE simply change memory but leave empty

E - Announce speed
W - change speed with LEFT (plus) and RIGHT (minus) paddles.
M - change COMMAND mode speed

F - Change monitor frequency, use paddles for higher or lower frequency
O - toggle Monitor ( cycles through BOOP OFF, short BEEP ON, long BEEP ON only in paddle mode, not memories )

A - Switch to Iambic A mode
B - Switch to Iambic B mode
C - Switch to Single Paddle Mode
D - Switch to Ultimatic mode
G - Switch to Bug mode
T - Tune mode press RIGHT paddle for permanent Tune, LEFT paddle for intermittent Tune

H - Set weighting and dah to dit ratio to defaults
I - TX enable / disable
J -  Dah to dit ratio adjust
K - Toggle Dit and Dah Buffers on and off (Ultimatic Mode)
L -  Adjust weighting
N - Toggle paddle reverse
Z - Autospace On/Off

? sends status
1) Speed in WPM
2) Keyer Mode (A = Iambic A, B = Iambic B, G = Bug, S = Single Paddle, U = Ultimatic)
3) Weighting
4) Dah to Dit Ratio