jks
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v1.391,392,393,394: New noise blanker and filters
From the CHANGE_LOG file:
This filter is on the main control panel, audio tab, "noise > filter" menu. Click the "more" button to the right of the menu to adjust the filter parameters, although the filter works well with the defaults. In some cases you might have to increase the filter gain to match the filter-off level, especially during A/B comparisons. Try it with a weak station on the AM broadcast band or ham band SSB signal.v1.394 May 31, 2020 Noise blankers and filters: Added the spectral noise reduction filter by Frank, DD4WH and Michael, DL2FW, via the Teensy-ConvolutionSDR and UHSDR projects. See: github.com/df8oe/UHSDR/wiki/Noise-reduction This noise filter works really, really well. Especially for voice signals. A good alternative to the LMS filters. Note that the Wild blanker and all the noise filters (wdsp, LMS, spectral) don't currently work with the modes: IQ, SAS and DRM (i.e. the 2-channel IQ modes). This will be fixed at some point.
Note that some noise filters always require their sections be enabled via the "more" panel. Otherwise simply selecting their menu entry does nothing. In particular the wdsp and LMS filters since they have independent denoiser and autonotch sections that are enabled separately (or both simultaneously). -
v1.391,392,393,394: New noise blanker and filters
From the CHANGE_LOG file:
This filter is on the main control panel, audio tab, "noise > filter" menu. Click the "more" button to the right of the menu to adjust the filter parameters, although the filter works well with the defaults. In some cases you might have to increase the filter gain to match the filter-off level, especially during A/B comparisons. Try it with a weak station on the AM broadcast band or ham band SSB signal.v1.394 May 31, 2020 Noise blankers and filters: Added the spectral noise reduction filter by Frank, DD4WH and Michael, DL2FW, via the Teensy-ConvolutionSDR and UHSDR projects. See: github.com/df8oe/UHSDR/wiki/Noise-reduction This noise filter works really, really well. Especially for voice signals. A good alternative to the LMS filters. Note that the Wild blanker and all the noise filters (wdsp, LMS, spectral) don't currently work with the modes: IQ, SAS and DRM (i.e. the 2-channel IQ modes). This will be fixed at some point.
Note that some noise filters always require their sections be enabled via the "more" panel. Otherwise simply selecting their menu entry does nothing. In particular the wdsp and LMS filters since they have independent denoiser and autonotch sections that are enabled separately (or both simultaneously). -
v1.391,392,393,394: New noise blanker and filters
From the CHANGE_LOG file:v1.392,393 May 28, 2020 Noise blankers and filters: Added the Michael Wild noise blanker. Not a lot of operating experience with this yet. It seems not to work on some noise sources compared to the standard blanker. A good test source is 100 kHz Loran-C in AM mode using a UK Kiwi. Increase the gate time (standard blanker) or impulse samples (Wild blanker) to account for the longer Loran-C pulses compared to the usual impulse noise. Fixed wdsp filter: the control sliders had no effect previously! Now it works quite well. You have to adjust the gain carefully to prevent overload. Added test pulse gain and pulse width controls. And also whether the pulse is applied before or after the passband filtering. The Wild blanker seems only effective on post-filter pulses. Probably because the filter is turning the pre-filter step function pulses into nicer band-limited pulses.
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v1.391,392,393,394: New noise blanker and filters
From the CHANGE_LOG file:v1.392,393 May 28, 2020 Noise blankers and filters: Added the Michael Wild noise blanker. Not a lot of operating experience with this yet. It seems not to work on some noise sources compared to the standard blanker. A good test source is 100 kHz Loran-C in AM mode using a UK Kiwi. Increase the gate time (standard blanker) or impulse samples (Wild blanker) to account for the longer Loran-C pulses compared to the usual impulse noise. Fixed wdsp filter: the control sliders had no effect previously! Now it works quite well. You have to adjust the gain carefully to prevent overload. Added test pulse gain and pulse width controls. And also whether the pulse is applied before or after the passband filtering. The Wild blanker seems only effective on post-filter pulses. Probably because the filter is turning the pre-filter step function pulses into nicer band-limited pulses.
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v1.391,392,393,394: New noise blanker and filters
From the CHANGE_LOG file:v1.391 May 23, 2020 User interface changes: SAL, SAU mode passband image will only show single sideband (just like LSB, USB). Ctrl/alt-click on mode button toggles modes backwards (most useful with SAM modes). Same works with keyboard shortcuts, e.g. ctrl/alt-A toggles SAM modes backwards. Noise blankers and filters: Reworked the audio tab user interface to support multiple blanker/filter algorithms. New algorithms planned but not yet available are greyed-out in the menus. From Warren Pratt's wdsp package added the variable-leak LMS algorithm. Merged Howard Su's RPi changes. Note: RPi is not officially supported by KiwiSDR. Ask for help on the KiwiSDR forum: http://forum.kiwisdr.com/discussion/1986/port-kiwisdr-to-raspberrypi-3b Bug fixes: Audio recordings made in SAS (synchronous AM stereo) mode now work. Fixed problem with ITU region 2 Kiwis and shift-clicking waterfall in 75/80m band segment. from lazywalker: fixed problems with frequency memory and reload value when transverter offset used.