Typo: Change "...or in the case of PLL designs, VCOs with a much higher C/L ratio than the K3..."
to "...or in the case of PLL designs, VCOs with a much *lower* C/L ratio than the K3." Wayne N6KR On Aug 31, 2014, at 7:17 PM, Wayne Burdick <[email protected]> wrote: > Jim, > > Thanks for your analysis of transmitted phase and keying noise of various > transceivers. I'd like to provide a couple of technical details, and to give > credit where it is due. > > To achieve the excellent results shown in your paper for the K3, we used a > combination of four techniques: > > 1. A hybrid PLL/DDS synthesizer with a very high C/L ratio VCO: Many of the > radios shown in your plots use unfiltered DDS for their VFO, or in the case > of PLL designs, VCOs with a much higher C/L ratio than the K3. Both of these > design decisions can increase phase noise and dynamic artifacts. To preserve > a consistently high C/L ratio, we use up to 128 different C/L combinations as > the VCO is band-switched. (This is in contrast to the usual 1, 2, or 3 VCO > C/L ranges used in other rigs.) We also used very narrow-band crystal > filtering of the DDS output to completely remove any of the usual spurs due > to quantization, etc. John Grebenkemper assisted greatly with the synthesizer > design. ______________________________________________________________ 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 Message delivered to [email protected]
