Side question: Does anyone know the exact location of the temperature sensor for the FP reading on the K3?
> From: chadwasin...@outlook.com > To: kl...@acsalaska.net; elecraft@mailman.qth.net > Date: Mon, 4 Feb 2013 09:24:44 -0600 > Subject: Re: [Elecraft] KTCXO3-1 TCXO > > Thanks you all for responding to this. I also note that it takes around an > hour for the larger corrections to settle down and several hours for complete > stability to set in. > I've been monitoring my front panel temperature sensor which normally runs 36 > C with the radio on for several hours and a shack temperature of 75 F > degrees. From a cold start up at 24 C, it normally takes about an hour to > reach a constant temperature of 36 C on the FP. I know the FP temp reading > and TCXO are separate pieces but at the point of 36 C, I have really notice > the TCXO to settle out. > > Date: Sun, 3 Feb 2013 09:22:57 -0900 > > To: Elecraft@mailman.qth.net > > From: kl...@acsalaska.net > > Subject: [Elecraft] KTCXO3-1 TCXO > > > > Date: Sun, 3 Feb 2013 08:45:36 -0600 > > From: Chad Wasinger <chadwasin...@outlook.com> > > To: "elecraft@mailman.qth.net" <elecraft@mailman.qth.net> > > Subject: [Elecraft] KTCXO3-1 TCXO > > Message-ID: <bay002-w97bd9bbec8db9494e84bf3c0...@phx.gbl> > > Content-Type: text/plain; charset="iso-8859-1" > > > > Does anyone know the approximate warm-up/stabilize time of the KTCXO3-1? > > Thanks,ChadN0YK > > ---------------- > > Chad, > > > > I observed the action of my TCXO3-1 closely after initial > > installation of the EXREF. I noted from cold start up that the TCXO > > was receiving a continued updated offset for about 20 to 30 minutes, > > whereby it stabilized out at about an offset of about 78-80. From > > that time on the offset would only wander a couple points over several > > minutes. > > > > A check of my 28-MHz transmit frequency accuracy was within 2-Hz > > (indicating 0.1 ppm) and would only occasionally change by 1-Hz > > reflecting the slow drift of the TCXO between reference checks with > > the external 10-MHz source. Running the TCXO-3 without the EXREF > > accuracy is aprox. 0.5ppm or on 28-MHz this translates to a maximum > > error of +/- 14-Hz. > > > > Freq. measurements are made with an EIP-538 microwave counter that is > > referenced to a Rubidium 10-MHz reference. The K3EXREF is referenced > > to a separate OCXO which is run on a battery full-time. Short-term > > stability of the OCXO is +/-5 E-12, Long-term stability is +/-5 E-5 > > which requires adjustment about every four months to correct about > > 1-Hz long-term drift. I have a 200K ten-turn helipot for adjusting > > the OCXO frequency. I use my Rubidium as frequency reference which > > is +/- 5 E-11 after 30-min warmup. GPS is more accurate but I find > > the Rubidium sufficient for my needs. eg: 10-MHz is 1.0 E+7, > > multiplied by 5 E-11 = 5.0 E-4 Hz = 0.0005 Hz > > > > See details of the EXREF (and TCXO3-1): > > http://www.kl7uw.com/K3EXREF.htm > > > > 73, Ed - KL7UW > > > > ______________________________________________________________ > > 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
