Dan, I cannot imagine ham radio application that requires stability and accuracy better than standard K3 oscillator with K3EXREF, provided your reference oscillator is good enough for the toughest amateur radio application. Don't forget, with K3EXREF you still need some external reference oscillator, either good calibrated OCXO, some kind of timing module based on GPS technology (like Thunderbolt etc.) or Rubidium oscillator, like Symmetricom/Datum LPRO or one of the FEI products. Note that in case of OCXO, it will need to be periodically calibrated against better reference. However, if you plan to use K3 on the go without k3EXREF and need better accuracy/stability, then you probably want to consider KTCXO3. Using permanently KTCXO3 with K3EXREF seems like waste of money, this will not give much advantage over same setup with standard K3 oscillator. 73, Igor, N1YX
-----Original Message----- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Dan AE9K Sent: Friday, May 20, 2011 10:48 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Installed K3EXREF Ed, Thanks for the response. Let me clarify my question. I'm wondering if the KTCXO3 0.5 ppm oscillator can be omitted and still get great results with the K3EXREF and the standard 5 ppm oscillator. This is of interest because I intend to acquire the K3EXREF but do not have the KTCXO3 and would prefer not to buy it if it doesn't add any benefit. My logic: If the K3EXREF adjusts the TCXO (via REF CAL) every 4 seconds, then why not let it adjust the standard K3 TCXO instead of having it adjust the optional KTCXO3 oscillator? Even though the two oscillators differ by an order of magnitude in their error, does that error make a difference when the K3EXREF adjustments are every four seconds? ps - During your beta testing were you using the standard K3 5 ppm oscillator or the KTCXO3 0.5 ppm oscillator? I didn't find mention of that on your web site. Dan AE9K -- View this message in context: http://elecraft.365791.n2.nabble.com/Installed-K3EXREF-tp6188288p6388532.htm l Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ 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