I'd say that could indicate a build problem with your rig; but the thing to do is log in on the terminal and run the hardware diagnostic tools, in particular, the RF Sweep tool. Compare your results to what you see in the operating manual. If you are way off (such as, the vertical scale peak is much lower than what you see in the manual), then it indicates a build problem! But if you see similar results to what is in the operating manual, then you don't have a problem with the ADC on your QMX itself.?
Furthermore?you should check the Band Configuration screen; the default gain on each band is 54 which is normally about right.?
If all that looks correct... I'd say something on your PC may be incorrectly configured. But I'm not a Windows guy since several?years now.?
On Wed, Aug 9, 2023 at 7:22?PM Mike KK7ER <groupio@...> wrote:
Hans, thank you for trying it --?I'm glad to know it is working on Linux. Alan, I went ahead and enabled "listen to this device" but it does not change anything for me. I tried it on a third Windows machine but he behavior is exactly the same:? successful Audacity recording from QMX Transceiver device but audio is silent. On the same machine, WSJT-X displays a nice waterfall proving that it is successfully streaming in the audio.
However... Examining the recorded audio more carefully, it looks like it is not completely quiet. But the PCM audio only takes up roughly the 5 least significant bits out of 24 bits total. If I amplify by about 50dB in Audacity and play back I can hear the FT8 signals. 5 bits might be enough for WSJT-X to decode some signals but that's really leaving a lot of PCM audio representation accuracy on the table. Now I'm wondering if there is some issue with my build where the audio level at the QMX ADC is too low. I don't have an oscilloscope (or the time right now) to dive into it and find out. I have made a few CW and FT8 contacts so the rig is usable but it sure seems like it could utilize the dynamic range of that 24-bit DAC a lot better than it currently is.
Hans, is this something that will be fixed when AGC is implemented or does it indicate a build problem with my rig? Thanks!
