Like many mobile radios Alinco DX-SR8 doesn’t provide audio output on the mic connector so we’ll have to go with a split cable. You can use an existing split cable (1, 2) as a starting point and replace the mic connector.
We’ll need confirmation on the exact model of the aviation connector needed, let’s call it GX??-8F.
The cable pinout as follows:
GX??-8F pin 1 (MIC) → 3.5mm TRRS ring 1 (RIG_AFIN)
GX??-8F pin 2 (PTT) → 3.5mm TRRS ring 2 (PTT)
GX??-8F pin 8 (GND) → 3.5mm TRRS sleeve (GND)
GX??-8F pin 7 (MIC GND) → GX??-8F pin 8 (GND)
3.5mm TRS tip (SP) → 3.5mm TRRS tip (RIG_AFOUT)
3.5mm TRS sleeve (GND) → 3.5mm TRRS sleeve (GND)
Please post your results if you end up building this cable.