Ashhar Farhan VU2ESE has published the design of the uBITX 10 watt SSB HF transceiver covering the 3.5-30 MHz amateur radio bands 

The uBITX is based on an Arduino controller and one Si5351 for all the local oscillators. The Double conversion, superhet architecture transceiver can be built for less than $50 and a modest stocked junk box.

Article and Video - http://www.phonestack.com/farhan/ubitx/ubitx.html