In the mean time, clever Guido PE1NNZ, has come up with a modification of the QCX that turns a simple CW radio with class E output into a software defined SSB capable radio. The great thing is that it's open source and being actively developed.
From Soldersmoke: "The SSB transmit-stage is implemented in a completely digital and software-based manner: at the heart the ATMEGA328 is sampling the input-audio and reconstructing a SSB-signal by controlling the SI5351 PLL phase (through tiny frequency changes over 800kbit/s I2C) and controlling the PA Power (through PWM on the key-shaping circuit).
In this way a highly power-efficient class-E driven SSB-signal can be realized; a PWM driven class-E design keeps the SSB transceiver simple, tiny, cool, power-efficient and low-cost (ie. no need for power-inefficient and complex linear amplifier with bulky heat-sink as often is seen in SSB transceivers)."
There is an active discussion board about the evolving circuit and parts bill of materials (BOM) on groups.io here.
There are two board designs, one is a "sandwich" that supports multiple bands, the other is a single board shown above. (Photo by Dan Reynolds posted in the group).
The CAD files for the board, now at revision 1.02 are available in the group and I found someone selling them on Ebay so I ordered there (currently sold out).
While I have some of the parts on hand I decided to order the full parts list from Digi-Key and this would normally be a tedious task but I've found the secret! Digi-Key has a feature called BOM management.
- From the files area on groups.io get the file “Bom_8397236.csv”
- Log in to Digi-key
- Choose BOM manager from the menu top right
- Click upload bom, select the CSV file.
- Adjust the column headers to make sure digi-key product codes and quantity are correct.
- Click Add to BOM.
- Click Add to cart.