There are many variants of transceivers labeled as or related to “uSDX”. These radios use different connections. For some of them there are store cables [1, 2], for others there are no pre-made cables available in store at this time.
The radios in the pictures below will need homebrew cables:
uSDR Clone Manual.pdf (378.0 KB)
uSDRplus_red_corners.pdf (223.6 KB)
According to the information in the manuals the pinout for the mic connector looks like this:
Would love to hear the logic behind the decision to use ring 1 for ground connection. Anyway, based on this pinout the audio cable to Digirig will look like this:
3.5mm TRRS tip (MIC) → 3.5mm TRRS ring 1 (RIG_AFIN)
3.5mm TRRS ring 1 (GND) → 3.5mm TRRS sleeve (GND)
3.5mm TRRS ring 2 (PTT) → 3.5mm TRRS ring 2 (RIG_PTT)
3.5mm TRRS sleeve (SPK) → 3.5mm TRRS tip (RIG_AFOUT)
Please report your results if you end up building the cable.