nanoKeyer -Extensions


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.