>I think the LO phase noise should be pretty close. Perhaps it *should* be... but some of the worst examples of wideband transmitted noise are caused by additional amplitude noise in the TX chain, or by poorly filtered DAC noise in SDR-based transceivers [1]. These noise sources are additional to the LO noise, and are present whenever the rig is in TX mode (even without modulation).
That unfounded *belief* that "the LO phase noise should be pretty close" was precisely the reason why none of the designers paid any attention to the excess transmitter noise. But the equipment reviews were equally at fault for failing to draw attention to the problem. [1] Band Pollution from Amateur Transmitters - SM5BSZ http://sm5bsz.com/dynrange/dubus313.pdf 73 from Ian GM3SEK >-----Original Message----- >From: [email protected] [mailto:elecraft- >[email protected]] On Behalf Of K9MA >Sent: 10 June 2018 20:14 >To: [email protected] >Cc: [email protected] >Subject: Re: [Elecraft] Field Day rig experience > >I think the LO phase noise should be pretty close. > >---------- > >Scott Ellington. K9MA > > --- via iPhone > >> On Jun 10, 2018, at 1:17 PM, Jim Brown ><[email protected]> wrote: >> >>> On 6/9/2018 12:54 PM, K9MA wrote: >>>> On 6/9/2018 14:52, David Gilbert wrote: >>>> I think another major concern for closely positioned rigs would be >transmitted phase noise, and of course that doesn't show up in the >Sherwood charts. >>> >>> Yes, it does! >> >> All I've ever seen from Rob is RX phase noise. Can you provide a link >to TX phase noise? The TX phase noise data I've published came from >ARRL Labs. >> >> 73, Jim K9YC >> >> >__________________________________________________________ >____ >> 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] > >__________________________________________________________ >____ >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] ______________________________________________________________ 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]
