I have used the QYT 8900D as a cheep node radio - on low power the TX seems to live (has a tiny fan) and there is room inside the case for a CM-108 board with a USB Cable extension. I remove the mic and use the 8Pin Jack for PTT and Mic IN. There is a transistor that powers the audio amp and provides a receiver unsquelched line, and the vol ctl high has a fixed receive audio - all emphasized and de-emphasized (wish there was flat in and out but so far no joy)…
I have used this radio on ASL2.0.0 beta 6 with no problems. I tried a new ASL REV 3 and did have a small problem. I had to run the RX gain up to 995/1000 to get sufficient input (Rev3) and got reports of muffled - no high’s and watery (what does that mean) audio… Tried a 2nd computer (same radio / interface) with 2.0.0 beta 6 - sounds great…
The difference was in Rev 3 - I had the 20 dB RX attenuator engaged and the beta 6 did not. RX setting on 2.0.0 beta 6 is 85/1000 and sounds great. When I removed the attenuator on the Rev 3 the watery / no highs - etc went away.
Also somewhere in the mix - I ran the RX at 995/1000 (Rev 3) with the atten removed (massive overdrive on receive) and DTMF decode quit working - to be expected - just some casual observations… I do have an active repeater - GE M3 in Waco on REV 3 working flawlessly - Good Work Folks !!! de nu5d