I've applied the following extension to my nanoKeyer:

  • Powersupply
  • Memory bank selection
  • smaller code changes




The Arduino nano board has a direct input to its 5V regulator. When applying 13.8V to this input, the regulator gets a little bit hot. This simple circuit


reduces the the input voltage about 3.2V, which helps to keep the regulator cooler. Additionaly a reverse-polarity protecion circuit and a rf-filter is provided.

Memory bank selection

On the current nanoKeyer circuit board, only three memory keys and the command key are available. Usually I work /qrp and /p so I don't want to reprogramm the memories constantly.

I've added a single-pole, three position switch to select te memories 1-3, 4-6 or 7-9 on the three memory buttons.


The sketch has to be updated, to support the switch settings correctly.

    {include_code_listing /var/www/web4/html/joomla/images/stories/nanokeyer/NeueButtons.ccp}

    The updated sketch can be downloaded from here.

    Code updated to the Say-Hi Feature

    The Say-Hi feature is coded a little bit "ugly". I've updated the feature this way:

    {include_code_listing /var/www/web4/html/joomla/images/stories/nanokeyer/FeatureSayHi.cpp}

    The keyer now sends my call during power-up even if the sidetone is switched of. The state of the transmitter key is also save correctly.


    2014 CW (Morse Telegraphy) was added to the German Nationwide Inventory of Intangible Cultural Heritage.

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