Re: XV Transverter Local Oscillator -- GPSDO?
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I have achieved frequency stability to 1 Hz with the Flex-1500 & Elecraft
XV144 transverter combination, using a GPS disciplined OCXO on 116 MHz. I have documented the XV144 frequency stability and drift data comparing the GPS control against the stock crystal oven option with enhanced thermal insulation here https://picasaweb.google.com/114032640816757126398/XV144FrequencyStabilityModifications The stock FLEX-1500 TCXO is sufficient to hold the frequency to within 1 Hz. Enabling the 10 MHz sine wave external reference on the FLEX-1500 should increase the frequency accuracy and stability to the millihertz range. Carol, KP4MD *Bill Schwantes* bill4070 at gmail.com <elecraft%40mailman.qth.net?Subject=Re:%20%5BElecraft%5D%20XV%20Transverter%20Local%20Oscillator%20--%20GPSDO%3F&In-Reply-To=%3CCAFyNi86U3UyF%2Bu2eTUX0oG3pE%3D7zXb0VgjbijP8_xzgZGxXh%3DQ%40mail.gmail.com%3E> *Thu Oct 20 00:57:06 EDT 2011* - Previous message: [Elecraft] W2problems<http://mailman.qth.net/pipermail/elecraft/2011-October/157966.html> - Next message: [Elecraft] AF peak filter<http://mailman.qth.net/pipermail/elecraft/2011-October/157969.html> - *Messages sorted by:* [ date ]<http://mailman.qth.net/pipermail/elecraft/2011-October/date.html#157968> [ thread ]<http://mailman.qth.net/pipermail/elecraft/2011-October/thread.html#157968> [ subject ]<http://mailman.qth.net/pipermail/elecraft/2011-October/subject.html#157968> [ author ]<http://mailman.qth.net/pipermail/elecraft/2011-October/author.html#157968> ------------------------------ Hi Guys and Gals, Does anyone know of a mod to the Elecraft XV transverters that provides for 10 Mhz GPS disciplined oscillator control of the transverter local oscillator? I think that would be a popular feature for Elecraft to consider on future versions of XV transverters. It would be similar to the K3EXREF Frequency Lock Option for the K3, which works flawlessly. Bill, W7QQ ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Carol, KP4MD/W6
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The GPS reference we used was engineered by N6GN specifically for members
of our 2 meter WSPR study group listed on http://www.qsl.net/kp4md/144_mhz_wspr.htm That discussion thread can be followed at https://groups.google.com/forum/#!topic/2-meter-wspr/-hDK071K1iM A ready made solution to produce a 116 MHz local oscillator locked to a 10 MHz GPS disciplined reference is N5AC's VHF ApolLO at http://www.n5ac.com/blog/products-page/apollo-synthesizers/vhf-apollo-assembled-tested/ Carol KP4MD On Tue, Jul 2, 2013 at 3:50 AM, David G4DMP <[hidden email]> wrote: > Hello Carol - > > Thank you so much for your msg on the Elecraft reflector; I found your > slide show most interesting. > > I use my XV144 with a K2. I have the crystal oven option and have also > installed an internal fan similar to that fitted as standard to the > XV432. Stability is not bad but certainly not good enough for WSPR or > PSK32. > > I do have a GPS disciplined 10MHz standard. All I need now to follow > your example is to find a means of getting 116MHz from it to lock the > XV144. Do you have any circuit information of the PLL? > > Thanks again for your superb website. > > 73 > > David G4DMP > Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Carol, KP4MD/W6
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In reply to this post by kp4md
As I added the insulation and fan modifications just to stabilize the
internal 116 MHz local oscillator, I feel certain that they are not necessary when using a GPS disciplined LO like N5AC's VHF ApolLO. That was an alternative I did consider before our own group project GPS10 became available. I would have fed the 10 MHz signal through the AUX BNC connector to a VHF ApolLO installed inside the Elecraft XV144 case. Anyway, I have left the fans running as I like to see the Elecraft transverter run cool. Carol On Tue, Jul 2, 2013 at 8:59 AM, Bill Schwantes <[hidden email]> wrote: > Carol, > > You've done some nice work here, by identifying XV temperature sensitive > oscillator components other than the crystal. > > I'm curious to see if the demonstrated stability could be reproduced > without the insulation and fan modifications you made...... just the GPS > disciplined 116 Mhz injection. If that works, one could package a GPS > disciplined PLL synthesized oscillator board directly into the XV144. A > board such as this is available from Steve Hicks, N5AC (and other sources). > There are a number of approaches to minimizing PLL phase noise. If you are > interested in those references, let me know. > > Bill, W7QQ > > > > On Mon, Jul 1, 2013 at 4:21 PM, Carol F. Milazzo, KP4MD/W6 < > [hidden email]> wrote: > >> I have achieved frequency stability to 1 Hz with the Flex-1500 & Elecraft >> XV144 transverter combination, using a GPS disciplined OCXO on 116 MHz. I >> have documented the XV144 frequency stability and drift data comparing the >> GPS control against the stock crystal oven option with enhanced thermal >> insulation here >> https://picasaweb.google.com/114032640816757126398/XV144FrequencyStabilityModifications >> >> The stock FLEX-1500 TCXO is sufficient to hold the frequency to within 1 >> Hz. Enabling the 10 MHz sine wave external reference on the FLEX-1500 >> should increase the frequency accuracy and stability to the millihertz >> range. >> >> Carol, KP4MD >> >> >> >> >> *Bill Schwantes* bill4070 at gmail.com <elecraft%40mailman.qth.net?Subject=Re:%20%5BElecraft%5D%20XV%20Transverter%20Local%20Oscillator%20--%20GPSDO%3F&In-Reply-To=%3CCAFyNi86U3UyF%2Bu2eTUX0oG3pE%3D7zXb0VgjbijP8_xzgZGxXh%3DQ%40mail.gmail.com%3E> >> *Thu Oct 20 00:57:06 EDT 2011* >> >> >> - Previous message: [Elecraft] W2problems<http://mailman.qth.net/pipermail/elecraft/2011-October/157966.html> >> - Next message: [Elecraft] AF peak filter<http://mailman.qth.net/pipermail/elecraft/2011-October/157969.html> >> - *Messages sorted by:* [ date ]<http://mailman.qth.net/pipermail/elecraft/2011-October/date.html#157968> >> [ thread ]<http://mailman.qth.net/pipermail/elecraft/2011-October/thread.html#157968> >> [ subject ]<http://mailman.qth.net/pipermail/elecraft/2011-October/subject.html#157968> >> [ author ]<http://mailman.qth.net/pipermail/elecraft/2011-October/author.html#157968> >> >> ------------------------------ >> >> Hi Guys and Gals, >> >> Does anyone know of a mod to the Elecraft XV transverters that provides for >> 10 Mhz GPS disciplined oscillator control of the transverter local >> oscillator? >> >> I think that would be a popular feature for Elecraft to consider on future >> versions of XV transverters. It would be similar to the K3EXREF Frequency >> Lock Option for the K3, which works flawlessly. >> >> Bill, W7QQ >> >> > Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Carol, KP4MD/W6
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