On Wed, Mar 7, 2012 at 10:20 PM, Wayne Burdick <n...@elecraft.com> wrote: >...This is a substantial departure from other SDRs..... ---------------- Yep, for sure. And the biggest departure from the typical ham SDR is the fact that the computer is inside the radio box. There are various commercial and non-commercial SDRs in use on the ham bands, but nearly all of them rely on the PC to do filtering, detection, and other stuff. At first this had a certain irresistible gadget-lover's appeal, but when you stop to think about it, it's not surprising that it opens up a can with a nearly infinite number of worms.
The processing inside the PC introduces latency which is aggravated by delayed procedure calls, an operating-system process that happens when certain interrupts happen at certain times. This can mess up performance both on receive and transmit. Moreover, the programming involved is complicated. To replicate all the functions of a competitive ham transceiver, a lot of code is required. When that code has to run in an environment where an unknown mix of other resource-hogging code is running, in an operating system not designed for real-time application, the complexity multiplies. The result can be an endless bug-squashing process, which has to start over every time there's a big change in the running environment (e.g. a new OS version). I sorta think that in the medium term the future of SDRs in ham radio will be those like the KX3, wherein the computer is completely devoted to the radio, using its own real-time OS, and handing off ancillary functions like the pan display to an external client. I don't think the KX3 is the last word by any means, because with a bigger CPU and different A/D gizmos you could obtain much wider bandwidth and more gadgetry. But at the moment, it's the thought-leader in the SDR sweepstakes. Tony KT0NY ---------- http://www.isb.edu/faculty/facultydir.aspx?ddlFaculty=352 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
