Well, the RXTX ensemble from fivedash http://fivedash.com/index.php?main_page=product_info&cPath=1&products_id=7&zenid=4cf546b7e8f700a9c92c1f2b8dd23ae1 costs only 90$ and is capable to use the Pi3 as a full blown transceiver, not just CW but also other digital modes and SSB as well... So, get yours ...