Joe, are you talking about the wdma_usb.inf file to disable the 20 dB mic boost? I have been searching around for details on making the inf change in Windows 10. I may be missing something in the search, but if you have modified the inf file for Windows 10, I would be really helpful if you have more details. I looked carefully through wdma_usb.inf and I can't see anything obvious. From windows 10 in my case.
Max NG7M On Sat, Aug 5, 2017 at 10:39 AM, Joe Subich, W4TV <[email protected]> wrote: > > On 8/5/2017 11:14 AM, Wes Stewart wrote: > >> But IMHO, you need to put a 30 dB attenuator on the input of the internal >> sound card; it is way too sensitive. I'm having to run the Windows gain at >> less than 5% and Line In at 10 or less. >> > > Actually, you need to adjust the options in the Windows *.inf file > used for the PCM-series CODEC (or use the codec that identifies as > line level). Windows is turning on a 20 dB preamp in the CODEC. > > I suspect if one sets the Windows Sound Options (Control Panel) to > display dB rather than percentage, the minimum level will be some- > thing like 16 to 20 dB! That indicated the fixed 20 dB "mic preamp" > is engaged. > > 73, > > ... Joe, W4TV > > > On 8/5/2017 11:14 AM, Wes Stewart wrote: > >> Wayne, >> >> There are no beat notes. These frequencies, at least from the FT8 program >> in Tune mode are single frequency. Based upon output RF spectrum >> measurements*, with for example 1010 Hz input and 4-5 bars of ALC, I see >> spurious or intermodulation sidebands, down -65 dBc. If I change nothing >> else but adjust the tone frequency to 1000 Hz the spectrum is the same but >> the ALC bars are cyclic, going from none to 4-5, at about the 2 HZ rate >> Brian reported earlier. (Slow ALC in action?) That's the good news. >> >> If I set the tone to 1500 Hz, the FT8 mid-band target, I'm presented with >> the cyclic ALC and some ~193 Hz, -50 dBc sidebands. >> >> I have tried this with both the K3S internal sound card and via Line >> In/Out into my laptop sound card. The results are more-or-less the same. >> But IMHO, you need to put a 30 dB attenuator on the input of the internal >> sound card; it is way too sensitive. I'm having to run the Windows gain at >> less than 5% and Line In at 10 or less. >> >> I would suggest that you do some measurements with a low-distortion sine >> wave audio source run into the radio to eliminate the possibility that this >> junk is a result of all of the digitally generated tones. >> >> If this (what I will call a) problem continues to exist then I think a >> fix is in order. Expecting users to select particular frequencies to use >> to set gain levels isn't an acceptable workaround. >> >> Regards, >> >> Wes N7WS >> >> >> * My "spectrum analyzer" is my SDR-IQ which I have used to measure TX IMD >> on both my K3 and K3S. Your IMD >> measurements on my K3S concurred with mine within 1 dB or less. >> >> On 8/4/2017 4:45 PM, Wayne Burdick wrote: >> >>> Is it possible that a beat note between tones (and their harmonics) is >>> what’s modulating the ALC reading? If so, moving the tone slightly off the >>> standard pitch may be an acceptable workaround. >>> >>> Wayne >>> N6KR >>> >>> >>> On Aug 4, 2017, at 1:42 PM, Wes Stewart<[email protected]> wrote: >>>> >>>> Good find Brian!!! I see it too in FT8. >>>> >>>> This probably explains the great variability in results reported. Some >>>> of us have a problem, others say, Huh, what the heck are you talking about? >>>> >>>> Wes, N7WS >>>> >>>> >>>> On 8/4/2017 11:33 AM, Brian Hunt wrote: >>>> >>>>> Here's some followup: >>>>> FLDIGI shows the "pumping" affect with carrier tones of 500, 1000, >>>>> 1500, and 2000 Hz. >>>>> WSJT-X 1.8 shows the "pumping" affect with carrier tones of 1000, 1500 >>>>> and 2000 Hz (couldn't select 500 Hz). >>>>> >>>>> The affect is very narrow with frequency. 10 Hz either way and the >>>>> output and ALC display and MON output is rock solid. Changing the K3 >>>>> filter center frequency has no effect on the above. >>>>> >>>>> 73, >>>>> Brian, K0DTJ >>>>> >>>>> On 8/4/2017 10:58, Brian Hunt wrote: >>>>> >>>>>> I spent some quality time with my K3, FLDIGI and an oscilloscope >>>>>> today. I had the same problem as described. Looking at my USB soundcard >>>>>> output to the K3, the amplitude of the audio from FLDIGI in TUNE mode was >>>>>> rock solid. Looking at the MON output from the K3, the level oscillated >>>>>> in >>>>>> time with the ALC "pumping" at about 2.4 Hz (timed with a stop watch). >>>>>> At >>>>>> the same time the K3 power output into a dummy load was rock solid at a >>>>>> selected 10 watts. >>>>>> >>>>>> Then I changed the carrier frequency in FLDIGI slightly off 1500 Hz >>>>>> and the "pumping" went away! At 1515 Hz I could easily set the ALC to >>>>>> the >>>>>> desired 4 bars solid, 5th flickering. Then I remembered (and verified) >>>>>> that the default filter center in DATA A mode is 1500 Hz. I changed the >>>>>> filter center frequency to 1450 Hz and moved the FLDIGI frequency around >>>>>> but couldn't reproduce the "pumping". >>>>>> >>>>>> I plan to repeat the same tests with WSJT-X 1.8 but wanted to get >>>>>> this out to the group. >>>>>> >>>>>> 73, >>>>>> Brian, K0DTJ >>>>>> >>>>>> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to [email protected] >> > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] > -- M. 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