It would not make sense to keep Software up to date on this Page.

Instead I´m showing you where to download the latest Version and how to adjust it for work with your Sandwich.

Go to Guido´s GitHub Page (into Branch -> Feature RX Improved)

The RX Improved Branch is a) way better in Performance then current Release Version „j“ and b) the only Version, that supports Relay switching at this time.

Click on the green „Code“ Button and select: Download Zip

Then you have a (compressed) copy of the most recent GitHub Content on your Hard Disk. For programming the Software into the uSDX you need also Arduino Studio Software and a cheap Arduino UNO Board (or compatible)

There need to be some very minor changes in code in order to match your Hardware Setup. After opening the INO File (with Arduino Studio) from your (QCX SSB) Download, you should see the following situation:

Those first lines of code are most of the available adjustment options. Made easily accessible for you.

Anything with „//“ in front of the line is disabled (greyed out) and anything without those 2 slashes in front, is active.

Let´s assume, we have and OLED IO Board and 8-Band RF Board.

What we need to change is:

  • Disable DIAG (not enough space together with OLED AND CAT)
  • -> If you´re running your sandwich 1st time, I´d suggest to leave DIAG on and disable CAT. This helps you with potential troubleshooting.
  • Enable OLED
  • Disable Rev 2 Relay Switching (= 5 Band Board)
  • Enable Rev 3 Relay Switching (= 8 Band Board)
  • Additional choices up to you (Do you want CW Keyer ? or streaming over CAT, Do you want to have CW QRP Frequncies by defalut when changing Bad ? etc)
  • Here´s my standard Setup for this: (changed lines marked)

This would be basically it, but there´s one hidden feature: The PA Output. If you want to Control PTT of an external PA, you additionally need to acticate one of the 2 Lines (depending of what your PA needs):

An the End of the Block // QCX pin defintions: (Line Numbers vary over Time)

Let´s say, our PA needs a PTT Signal, that is active LOW, then you need to remove // in front of #define NTX:

That´s it. Now you can save the File and upload it to your sandwich.

Another Example: LCD Board and 5-Band Board (This time with an older Software Version. Line Numbers are different now !

LCD Board does not support CAT Interface, so it can be disabled.

And we need to activate the right relay Board:

That´s all…..

Special Tip: After first installation, use a commercial rig, to find out your true crystal frequency. Go to Menu 8.1 Ref Freq, and adjust it. Exact procedure: Connect you uSDX to a Dummy load and set it to CW. Set your Commercial Rig to a Certain Frequency in Mode CW, and set the uSDX to the same frequency. Then TX (with uSDX into Dummy Load) and adjust „Ref Freq“ until you´re at zero beat / center of filter on your commercial rig. Write that frequency down. I put a sticker on every of my mainboards with the excact crystal frequency:

This frequency won´t change, so you can also enter that number directly into the INO File before next upload:

Additional Help how to program I have put together in this Video: