After a couple of hours struggling with the Yaesu FTX-1 internal soundcard, I came to the conclusion that this rig was for some reason not able to deliver ‘discriminated‘ sound output on the USB-soundcard outputs, that works with PDW. For some reason this FLEX (Used for Dutch P2000 pager messages, which is used by Dutch EMS) is really picky in how ‘raw‘ the signal is; slightly processed audio signals are not viable for proper decoding.

Since I do not have the proper DIN CAT-cable, I was also not able to get the 9600-baud stream including audio from the rig, so my hands were tied a bit.

So, I tried to use the HackRF Pro to try to receive and decode FLEX, which did work correctly. I had to install a virtual audio cable (acting like a microphone>speaker tunnel on a Windows machine), but after that I have a near 100% success rate on FLEX decoding.

I wish there was an easy way for the FTX-1 to just dump out unprocessed audio on the USB-soundcard interface, so it could be used for FLEX-decoding. Maybe I missed a crucial step, or it’s simply not possible, I don’t know.

However, it finally works with the HackRF. Yay!