At 09:58 AM 4/24/2008, Dave Blaschke wrote: >The best performance I can obtain for QSK is at the following settings: >GENERAL-AUDIO-Buffer: Size 512, Sample Rate: 48000 >GENERAL-OPTIONS: Process Priority: High >DSP: TX Buffer Size: 512, RX Buffer Size: 512 >Delay (ms): 10 (minimum setting) > >At these settings I see around 10% CPU utilization on the PowerSDR screen. > >With these settings, I am almost, but not quite there. Here is my >complaint. When returning from T to R there is an audible "pop" that >tends to mask reception during Dits and Dahs. I am wondering if >Receive recovery is occurring quickly enough.
In the SDR1K at least (and probably the F5K), there's no real analog component to the "recovery".. i.e. there's no amplifier to come out of saturation or AGC loop to recover. So what you're hearing is an artifact of how the software implements the changeover (i.e. switching the demodulated audio stream on and off when going in and out of Rx mode). > Elimination of the >"pop" on transition from T to R would go a long way in smoothing out >QSK, in my opinion. So that sounds like a leading edge shaping issue. Hmmm.. >My method of comparing QSK capability between my SDR-5000 and my >FT1000D is to select the frequency on a constant carrier signal, and >then key at 20 wpm to see how well I am able to hear the carrier >between Dits and Dahs. > > >Dave, W5UN > > >_______________________________________________ >FlexRadio Systems Mailing List >FlexRadio@flex-radio.biz >http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz >Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ >Knowledge Base: http://kb.flex-radio.com/ Homepage: >http://www.flex-radio.com/ _______________________________________________ FlexRadio Systems Mailing List FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kb.flex-radio.com/ Homepage: http://www.flex-radio.com/
