Most of the applications where "extreme accuracy" is really needed are transverters at microwave freqs. That is a lot of the feedback received here. I believe that. It makes the most sense.
A couple of PPM is plenty good for HF, imho. But there are those of us that have the frequency fetish. See the FMT for example. Dunno how many OO's have the capability to measure overall output to within a few Hz, nor how many can measure amplitudes to required levels of suppression. There must be some, and some are K3 owners. I got cited once, in 1973 by the FCC monitoring station in Kingsville, TX, when my dial marker was off by about 1 KHz. With the K3, nothing like that is a worry. But the K3EXREF makes it a certainty that you will have no excuse.... 73, matt W6NIA K3 #24 On Sun, 20 Mar 2011 21:12:19 -0400, you wrote: >Speaking of band edges.... > >During the recent ARRL DX SSB contest, there was a station operating on >7127. Because of the lower SB extending to 7124 (assuming 3k bandwidth) he >was operating out of the US phone band. He was a European but he was working >simplex. I bet there was an OO sitting there sending notices to every US >contact he made. > >If you KNOW your frequency to 1 Hz, you can legally operate with your dial >on 14149.9 and still be in the band. Likewise 7300.1. Also RTTY on 3601, >etc. etc. A super accurate transmitter has it's advantages :-) > >Jerry - K0TV > >----- Original Message ----- >From: "Matt Zilmer" <mzil...@verizon.net> >To: "Rick Stealey" <rstea...@hotmail.com> >Cc: <elecraft@mailman.qth.net> >Sent: Sunday, March 20, 2011 6:48 PM >Subject: Re: [Elecraft] Installed K3EXREF > > >> The K3EXREF is in field test now, as far as I know. It might be a >> little while before Elecraft puts it up for sale. >> >> "Extreme accuracy" probably has two psychological and one scientific >> source: >> - The need to put the K3 dead-on frequency is reassuring to folks that >> aren't sure it stays that way mostly as-is with the TCXO. >> - The desire to be a frequency authority, and be able to help others >> when they're off-freq. Hams with older rigs sometimes end up shifted >> off freq. On HF, I hear this a lot. >> - Knowing exactly what frequency you're on helps with band-edge >> issues, for example between the Extra-only CW sub-bands and the >> general CW sub-band. With a 1 Hz readout, this is seldom a problem, >> but it gets even better when the last digit also indicates the actual >> carrier freq. >> >> The K3 with just the stock TCXO holds the reference at somewhere below >> 1 PPM anyway. This is probably accurate enough for almost everyone, >> but some want near-perfect accuracy. GPS time has an uncertainty of >> around 0.3 nS, which is pretty low compared to 1PPM. No TCXO can beat >> that, but maybe an OCXO can? >> >> 73, >> matt W6NIA >> >> >> >> On Sun, 20 Mar 2011 14:45:59 +0000, you wrote: >> >>> >>> >>>Excellent posting by W9AC, a great reference, to be saved. >>>Now I wonder if it would be possible for someone to enlighten me as to >>>the need for such extreme accuracy? Is it because my K3 reads out to 1 Hz >>>but I can't really believe the absolute accuracy of that number unless I >>>get a K3EXREF? But if that is the case, my question would still remain, >>>wouldn't it? >>>Not that I need something else to put on my list ahead of my P3 and >>>sub receiver. >>>Rick K2XT >>> >>>______________________________________________________________ >>>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 >> ______________________________________________________________ >> 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 > > >______________________________________________________________ >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 ______________________________________________________________ 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
