Shortly this filter difference will be resolved. All filters, irrespective of sampling rate, will have the exact same shape factor as the 48000 Hz. Shortly after that, we will be able to support even better filters if the user can live with the latency through the RX chain and with this second change, we will have an extra benefit. We will be able to reduce the computational complexity at all sample rates to the minimum required by the bandwidth chosen for the filter up to some coding practicalities. This yoga/magic/dsp/software engineering should have been accomplished a long time ago and the code to do it has been in dttsp since the first day of its existence. The weekend I introduced 96000 and 192000, I should have done this at least 1/2 way step immediately and done this with the other code.
QRX for this as Frank and I discuss the design for this and he makes it fit into the dttsp v2.0 version of things. It will turn up in PowerSDR shortly thereafter in some form and I sure it will be greeted kindly by all. Bob N4HY Steve Kallal wrote: > I've have tried to achieve 512 buffers at 96 kHz. I'm not using 192 kHz > because I want a sharper CW rx filter shape. 192 kHz would be OK for SSB, > but on CW the display is too compressed. > > I can do 512 buffers at 96 kHz, but it gets unstable. CW break-in can crash > the system. The 5000A gets stuck in a state where the panadapter display > looks frozen even when changing the frequency. Cycling the 5000A power off > and back on again, gets me going again. I've found 1024 buffers fixes it. > Also listening to WWV has get choppy at 512. > > 1024 buffers are OK, except I would like to get the latency reduced. I am > using a 2.6 GHz P4 with 1 GB RAM. Is this typical with a P4 system? Would a > dual core help? I've tried two Firewire cards with the same results. I can > try to trim down Windows XP and turn off some services. > > The bottom line is I'd like to know if the buffer size for the sample rate > is typical, or if I need to do some system tweaks. > > 73, > > Steve N6VL > -- AMSAT Director and VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats, NJQRP, QRP ARCI, QCWA, FRC. ARRL SDR WG Chair “An optimist may see a light where there is none, but why must the pessimist always run to blow it out?” Descartes _______________________________________________ FlexRadio mailing list FlexRadio@flex-radio.biz http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archive Link: http://www.mail-archive.com/flexradio%40flex-radio.biz/ FlexRadio Knowledge Base: http://kb.flex-radio.com/ FlexRadio Homepage: http://www.flex-radio.com/
