Re: [Elecraft] [K3] KREF3 External Reference Option
Great news, I have been waiting for this option ever since my K3 arrived. The method implies the phase noise of the 10MHz reference is not so important - which is useful to know. My high spec reference is 5MHz and my cheap one 10MHz. The 10MHz will have worse phase noise than the TCXO in the K3 - though at the low frequencies it is not such an issue as it is at VHF and above. The 5MHz one is good - but it takes a long long time to lock. With the count method, it should not matter. Mike -- View this message in context: http://elecraft.365791.n2.nabble.com/KREF3-External-Reference-card-tp5143036p5865613.html Sent from the [K3] 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
Re: [Elecraft] [K3] KREF3 External Reference Option
All, Any chance of an external reference input for the K2? 73 K1NR k2 6xxx - Web mail provided by NuNet, Inc. The Premier National provider. http://www.nni.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
Re: [Elecraft] [K3] KREF3 External Reference Option
Perhaps there can be option to tell the MCU what frequency reference is used to accommodate users with 5MHz or 1MHz references, not only 10MHz. I assume there will be possibility to calibrate the internal oscillator to the good reference and then disconnect the reference till next time (say once a year or so). I hope there is no need to have the reference connected forever, right? 73 Igor N1YX Original Message from Wayne N6KR dated 14 June 2010 There appears to be more demand for this than we thought, so we're looking into it again. Note that our planned external reference implementation would not require an exact 49.38-MHz reference oscillator signal. It also doesn't require a pin-1 control voltage input on the TCXO module itself, as suggested earlier. It should work with any existing K3 TCXO, either +/- 5 or +/- 1 PPM. If you're interested, here are the details: A new REF-lock module would be designed that plugs into the small 8- pin connector near the top of the KREF3 PCB. The user's 10-MHz reference signal would be routed from the rear panel to the TMP connector on the KRE3 (this connector faces forward, into the DSP/ front panel area). A microcontroller on the REF-lock module would be clocked by the 10- MHz reference. If the signal were present, the microcontroller would continuously measure (and average) the frequency of the 49.38 MHz oscillator, obtaining a value to the nearest 1 Hz. Hysteresis would be applied to prevent hunting, so the actual accuracy spec would probably be +/- 2 Hz. This translates to about +/- 1 Hz in operating frequency on 20 m. Approximately once per second, the module would report the actual reference frequency to the K3's main MCU via a slow digital data line (labeled 100HZ on the RF and KREF3 schematics). The main MCU would use this to calibrate the REF CAL value normally entered by the user. There would be no noticeable impact on performance. If the 10 MHz external signal were not present, the user's normal REF CAL value would be used. Let me know if you have thoughts on this implementation. 73, Wayne N6KR __ 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
Re: [Elecraft] [K3] KREF3 External Reference Option
Love the thought of the ext 10 Mhz input. As I don't do portable with the K3, and I have the GPS 10 MHz available, why not??? Thanks Wayne. Merry Christmas. Mel, K6KBE From: Igor Kosvin k.i...@comcast.net To: elecraft@mailman.qth.net Sent: Fri, December 24, 2010 2:30:26 PM Subject: Re: [Elecraft] [K3] KREF3 External Reference Option Perhaps there can be option to tell the MCU what frequency reference is used to accommodate users with 5MHz or 1MHz references, not only 10MHz. I assume there will be possibility to calibrate the internal oscillator to the good reference and then disconnect the reference till next time (say once a year or so). I hope there is no need to have the reference connected forever, right? 73 Igor N1YX Original Message from Wayne N6KR dated 14 June 2010 There appears to be more demand for this than we thought, so we're looking into it again. Note that our planned external reference implementation would not require an exact 49.38-MHz reference oscillator signal. It also doesn't require a pin-1 control voltage input on the TCXO module itself, as suggested earlier. It should work with any existing K3 TCXO, either +/- 5 or +/- 1 PPM. If you're interested, here are the details: A new REF-lock module would be designed that plugs into the small 8- pin connector near the top of the KREF3 PCB. The user's 10-MHz reference signal would be routed from the rear panel to the TMP connector on the KRE3 (this connector faces forward, into the DSP/ front panel area). A microcontroller on the REF-lock module would be clocked by the 10- MHz reference. If the signal were present, the microcontroller would continuously measure (and average) the frequency of the 49.38 MHz oscillator, obtaining a value to the nearest 1 Hz. Hysteresis would be applied to prevent hunting, so the actual accuracy spec would probably be +/- 2 Hz. This translates to about +/- 1 Hz in operating frequency on 20 m. Approximately once per second, the module would report the actual reference frequency to the K3's main MCU via a slow digital data line (labeled 100HZ on the RF and KREF3 schematics). The main MCU would use this to calibrate the REF CAL value normally entered by the user. There would be no noticeable impact on performance. If the 10 MHz external signal were not present, the user's normal REF CAL value would be used. Let me know if you have thoughts on this implementation. 73, Wayne N6KR __ 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
Re: [Elecraft] [K3] KREF3 External Reference Option
Eugene, An external reference for the K2 would achieve nothing dynamically. The K2 stores its frequency information in EEPROM and retrieves that info during operation. The only time an accurate frequency reference would be a benefit to the K2 is during the dial calibration steps of adjusting the 4 MHz reference oscillator and then running CAL PLL and CAL FIL afterward. See the K2 Dial Calibration article on my website www.w3fpr.com for more information. Merry Christmas and a Happy New Year to all on the Elecraft reflector. 73, Don W3FPR On 12/24/2010 5:12 PM, Eugene Balinski wrote: All, Any chance of an external reference input for the K2? 73 K1NR k2 6xxx __ 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] [K3] KREF3 External Reference Option
Any news on the External Reference Option ? 73 Trevor G0KTN Original Message from Wayne N6KR dated 14 June 2010 There appears to be more demand for this than we thought, so we're looking into it again. Note that our planned external reference implementation would not require an exact 49.38-MHz reference oscillator signal. It also doesn't require a pin-1 control voltage input on the TCXO module itself, as suggested earlier. It should work with any existing K3 TCXO, either +/- 5 or +/- 1 PPM. If you're interested, here are the details: A new REF-lock module would be designed that plugs into the small 8- pin connector near the top of the KREF3 PCB. The user's 10-MHz reference signal would be routed from the rear panel to the TMP connector on the KRE3 (this connector faces forward, into the DSP/ front panel area). A microcontroller on the REF-lock module would be clocked by the 10- MHz reference. If the signal were present, the microcontroller would continuously measure (and average) the frequency of the 49.38 MHz oscillator, obtaining a value to the nearest 1 Hz. Hysteresis would be applied to prevent hunting, so the actual accuracy spec would probably be +/- 2 Hz. This translates to about +/- 1 Hz in operating frequency on 20 m. Approximately once per second, the module would report the actual reference frequency to the K3's main MCU via a slow digital data line (labeled 100HZ on the RF and KREF3 schematics). The main MCU would use this to calibrate the REF CAL value normally entered by the user. There would be no noticeable impact on performance. If the 10 MHz external signal were not present, the user's normal REF CAL value would be used. Let me know if you have thoughts on this implementation. 73, Wayne N6KR __ 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
Re: [Elecraft] [K3] KREF3 External Reference Option
Prototypes are working perfectly. We're getting ready for field testing. Wayne N6KR http://www.elecraft.com On Dec 22, 2010, at 4:41 PM, tsmith...@cix.co.uk (Trevor Smithers) wrote: Any news on the External Reference Option ? 73 Trevor G0KTN Original Message from Wayne N6KR dated 14 June 2010 There appears to be more demand for this than we thought, so we're looking into it again. Note that our planned external reference implementation would not require an exact 49.38-MHz reference oscillator signal. It also doesn't require a pin-1 control voltage input on the TCXO module itself, as suggested earlier. It should work with any existing K3 TCXO, either +/- 5 or +/- 1 PPM. If you're interested, here are the details: A new REF-lock module would be designed that plugs into the small 8- pin connector near the top of the KREF3 PCB. The user's 10-MHz reference signal would be routed from the rear panel to the TMP connector on the KRE3 (this connector faces forward, into the DSP/ front panel area). A microcontroller on the REF-lock module would be clocked by the 10- MHz reference. If the signal were present, the microcontroller would continuously measure (and average) the frequency of the 49.38 MHz oscillator, obtaining a value to the nearest 1 Hz. Hysteresis would be applied to prevent hunting, so the actual accuracy spec would probably be +/- 2 Hz. This translates to about +/- 1 Hz in operating frequency on 20 m. Approximately once per second, the module would report the actual reference frequency to the K3's main MCU via a slow digital data line (labeled 100HZ on the RF and KREF3 schematics). The main MCU would use this to calibrate the REF CAL value normally entered by the user. There would be no noticeable impact on performance. If the 10 MHz external signal were not present, the user's normal REF CAL value would be used. Let me know if you have thoughts on this implementation. 73, Wayne N6KR __ 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
