I suspected that was the case. I'm a little out of being current, but S/N on some of the devices I remember were not that great as compared to the better sound cards. 16 bits, ideally should allow 96 db dynamic range. However, you are correct, you don't get the full 16 bits. The oversampling and processing does buy you improvement, but you still need to contend with the 16 bits of quantization and the need to put some amplification ahead of the A/D to improve SNR. That gain should negatively impact on dynamic range. I, too, am waiting to see what Sherwood has to say. It should be interesting.
I do know this. Operating FD last year with a K3 and a KX3 using QRP power and from the same RV. The only problem we had was my KX3 LO being picked up by the K3. I forgot to turn on the isolation amplifier. Other than that, there was no problem. In the chaos of Field Day, the filtering appeared to be superb. 73, Barry K3NDM ----- Original Message ----- From: [email protected] To: "Barry LaZar" <[email protected]>, [email protected] Sent: Thursday, March 14, 2013 5:03:30 PM Subject: Re: [Elecraft] Wait For The K4 Direct RF Sampled SDR? I love my K3/P3/SVGA and my KX3 as well. I do want to mention that the new Flex 6000 series uses a 16-bit A/D, with over 245Ms/s sample clock, much better than 100Ms/s. Processing gain is real, and should help the 16-bit range somewhat, but 16-bits is not really 16-bits in the real world. Throw away at least 1/2 bit, and maybe more. It will be very interesting to see what a Flex 6000 series finally does in various receive parameters, especially dynamic range. They claim to handle a very large dynamic range, even without the various RF filters. I can't wait to see the Sherwood report on the 6000 series. 73, Terry, WB4JFI -----Original Message----- From: Barry LaZar Sent: Wednesday, March 13, 2013 10:13 AM To: [email protected] Subject: Re: [Elecraft] Wait For The K4 Direct RF Sampled SDR? I'm sort of curious about what Flex is doing with their new radio. The heart of it has to be a very good A/D converter, but the best thing I'm aware of is an Analog Devices 16 bit, 100 Msp/s one that ain't exactly cheap. To approach the dynamic range in the KX3 and the K3, 16 bits may be a might short. I, too, believe that direct sampling and high dynamic range is still a bit off particularly if you want to be able to afford one. I like the magic of my KX3 when used with NaP3 and a 24 bit, ASIO compliant sound card. As a practical matter, it serves for the 95% situations. those last five will include a lightning storm over my house or someone like W3LPL moving next door. 73, Barry K3NDM On 3/13/2013 9:49 AM, Wayne Burdick wrote: > No need to speculate. There is no such project underway at Elecraft. > > Direct RF-sampling receivers, for all their technology, still lag well > behind the K3 in blocking dynamic range, and probably will continue to for > years to come. We're quite happy with our superhet architecture. Also, any > advancement we make to the K3 will be retrofittable to existing K3s, so > your investment is safe. > > 73, > Wayne > N6KR > > > On Mar 12, 2013, at 8:04 PM, Bob Schumacher wrote: > >> Given the advances in direct RF sampled SDRs (currently available QS1R, >> soon to be released Flex-6000, etc.), Elecraft must be quietly working on >> on an RF sampled K4 SDR. Maybe we will see an anouncement in May at >> Dayton? I am wondering if I should take the leap with the Flex or wait >> for Elecraft? I suspect that Elecraft will provide a higher value >> solution. Any speculation on this point by Elecraft fans? >> >> Thanks, >> >> W9DBR >> ______________________________________________________________ >> 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 > > ______________________________________________________________ > 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 > ______________________________________________________________ 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 ______________________________________________________________ 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
