10 mHZ external reference VS the K3S's optional KTCXO3-1
Locked
10 mHZ external reference VS the K3S's optional KTCXO3-1
 
|
I've been following the thread on using a 10 mHZ external reference and the prospect seems both affordable and at least initially fun BUT I'd like to ask is it really a practical improvement over Elecraft's available KTCXO3 internal 1ppm reference? Or is this just a way to achieve more accuracy at less cost than the KTCXO3 ? Isn't the K3S better served with its own oscillator? What am I missing here?
Thanks, Doug W5JV / AFA6DL ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: 10 mHZ external reference VS the K3S's optional KTCXO3-1
|
|
One advantage it to lock all your gear to the same master oscillator.
From: Doug Hensley <[hidden email]> To: "[hidden email]" <[hidden email]> Sent: Monday, November 2, 2015 3:34 PM Subject: [Elecraft] 10 mHZ external reference VS the K3S's optional KTCXO3-1 I've been following the thread on using a 10 mHZ external reference and the prospect seems both affordable and at least initially fun BUT I'd like to ask is it really a practical improvement over Elecraft's available KTCXO3 internal 1ppm reference? Or is this just a way to achieve more accuracy at less cost than the KTCXO3 ? Isn't the K3S better served with its own oscillator? What am I missing here? Thanks, Doug W5JV / AFA6DL ______________________________________________________________ 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 Message delivered to [hidden email] ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: 10 mHZ external reference VS the K3S's optional KTCXO3-1
|
|
In reply to this post by Doug Hensley
Yes, I've been following this as well. And to that end, I have a
commercial GPS Disciplined Oscillator that is used as a reference for the test equipment in the shop. In checking my K3s I find, with the optional TCXO, the accuracy is typically +/-2 Hz on all bands. Few if many other transceivers will display or maintain this stand-a-lone accuracy. So I ask, what's the obsession with accuracy better than this for amateur use? 73 Bob, K4TAX On 11/2/2015 2:34 PM, Doug Hensley wrote: > I've been following the thread on using a 10 mHZ external reference and the prospect seems both affordable and at least initially fun BUT I'd like to ask is it really a practical improvement over Elecraft's available KTCXO3 internal 1ppm reference? Or is this just a way to achieve more accuracy at less cost than the KTCXO3 ? Isn't the K3S better served with its own oscillator? What am I missing here? ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: 10 mHZ external reference VS the K3S's optionalKTCXO3-1
|
|
Bob,
Thanks for asking, I too have struggled to understand the need given I only use the original digital mode, CW and SSB. :-) Gary -----Original Message----- From: "Bob McGraw - K4TAX" <[hidden email]> Sent: 3/11/2015 7:56 AM To: "[hidden email]" <[hidden email]> Subject: Re: [Elecraft] 10 mHZ external reference VS the K3S's optionalKTCXO3-1 Yes, I've been following this as well. And to that end, I have a commercial GPS Disciplined Oscillator that is used as a reference for the test equipment in the shop. In checking my K3s I find, with the optional TCXO, the accuracy is typically +/-2 Hz on all bands. Few if many other transceivers will display or maintain this stand-a-lone accuracy. So I ask, what's the obsession with accuracy better than this for amateur use? 73 Bob, K4TAX On 11/2/2015 2:34 PM, Doug Hensley wrote: > I've been following the thread on using a 10 mHZ external reference and the prospect seems both affordable and at least initially fun BUT I'd like to ask is it really a practical improvement over Elecraft's available KTCXO3 internal 1ppm reference? Or is this just a way to achieve more accuracy at less cost than the KTCXO3 ? Isn't the K3S better served with its own oscillator? What am I missing here? ______________________________________________________________ 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 Message delivered to [hidden email] ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: 10 mHZ external reference VS the K3S's optionalKTCXO3-1
|
|
Precisely or more accurately, accurate!
This pastime is no more inane than contesting or working QRP. On 11/2/2015 3:50 PM, Ron D'Eau Claire wrote: > IMX, such pursuits of precision become a hobby in themselves. > > ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: 10 mHZ external reference VS the K3S's optionalKTCXO3-1
|
|
We're talking about extreme precision here, but in somecases, it might be needed for MARS. I am not a member of MARS, soI am not privy to their current frequency tolerance requirements.But, at 1PPM, we're talking 10Hz at 10MHz.
I'm running a Trimble Thunderbolt GPSDO, and according to LadyHeather, I see a 10000 tau accuracy of 10 to the minus 13. Is thatextreme? Perhaps, for normal amateur use, but I think that it wouldprovide a decent "safety" margin for a MARS operator who needsto meet a certain frequency tolerance on a repeatable basis withno notice - i.e. instantly QSY to another frequency as needed, withoutworrying about how long it's been since the last formal calibration. (And, to be even more inane, the correct abbreviation is "MHz." -capital M for Mega, capital H/lower case Z for Hertz, since it's aunit named for a person, and is therefore capitalized. Lower caseM is for milli, which in this case might describe how far off thedesired frequency a signal might be if it were sync'ed to an externalsource with the degree of accuracy under discussion here...) I have a K3 with both the optional TCXO and the K3EXREF. Just my 20 millidollars' worth, N1HO From: Wes (N7WS) <[hidden email]> To: [hidden email] Sent: Monday, November 2, 2015 6:04 PM Subject: Re: [Elecraft] 10 mHZ external reference VS the K3S's optionalKTCXO3-1 Precisely or more accurately, accurate! This pastime is no more inane than contesting or working QRP. ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: 10 mHZ external reference VS the K3S's optionalKTCXO3-1
|
|
On 11/2/2015 4:57 PM, Bayard Coolidge, N1HO via Elecraft wrote:
> (And, to be even more inane, the correct abbreviation is "MHz." > -capital M for Mega, capital H/lower case Z for Hertz, since it's > aunit named for a person, and is therefore capitalized. Notwithstanding that the accepted abbreviation for 1000 Hz is kHz - lower-case k. I didn't learn that in engineering school because the Hertz hadn't been adopted yet. I love working with standards because there are so many of them to choose from. :) 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: 10 mHZ external reference VS the K3S's optionalKTCXO3-1
|
|
On 11/2/2015 8:19 PM, Ron D'Eau Claire wrote:
> n the Elecraft manuals and other technical writing I stick with the S.I. > standard notation. You can find details on line here; > > http://physics.nist.gov/cuu/Units/units.html > > The units are on that page and click on the link at the bottom for the > prefixes. That validates my posting that k = 1000 while M = 1,000,000 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon ______________________________________________________________ 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 Message delivered to [hidden email] |
|
|
When I started in the 1950s, we tuned kilocycles and announced Abel, Baker, Charlie, Dog, Easy, Fox.
A thousand was M, a million was MM, and Greek was a foreign language. Does current still flow from + to - in a circuit? If not, then most of my early electronics training was fanciful and my Elmers would be embarrassed were they not SK. Thanks for the NIST link. — Marc W8SDG > On Nov 3, 2015, at 12:34 PM, Phil Kane <[hidden email]> wrote: > > On 11/2/2015 8:19 PM, Ron D'Eau Claire wrote: >> n the Elecraft manuals and other technical writing I stick with the S.I. >> standard notation. You can find details on line here; >> >> http://physics.nist.gov/cuu/Units/units.html >> >> The units are on that page and click on the link at the bottom for the >> prefixes. > > That validates my posting that k = 1000 while M = 1,000,000 > > 73 de K2ASP - Phil Kane > Elecraft K2/100 s/n 5402 > > From a Clearing in the Silicon Forest > Beaverton (Washington County) Oregon > ______________________________________________________________ > 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 > Message delivered to [hidden email] ______________________________________________________________ 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 Message delivered to [hidden email] |
Re: 10 mHZ external reference VS the K3S's optional KTCXO3-1
|
|
In reply to this post by Doug Hensley
Doug,
Many do not understand what how K3EXREF improves accuracy and stability. Its commonly thought that its a phase locking system (which it is not doing). Basic frequency accuracy and stability is established by the TCXO in the K3 which provides frequency reference to the VFO's. Per Elecraft K3 manual - page: TCXO-1 is 5ppm and TCXO-3 is 1 ppm Using 28-MHz as an example: 5ppm = 28 E+6 x 5 E-6 = 28 x 5 = 140 Hz 1ppm = 28 E+6 x 1 E-6 = 28 Hz note these are +140 to -140 Hz and +28 to -28 Hz My measurement show that EXREF improves this to 0.1ppm 0.1ppm = 28 E+6 x 1 E-7 = 2.8 Hz* *ONLY IF you have the TCXO-3 installed. Also the TCXO is in warm-up for the first ten minutes after the K3 is powered on. EXREF corrects all the warm-up drift, as well, so you can start using the radio immediately without frequency accuracy concerns. HOW: The EXREF ckt provides a more accurate 10-MHz reference for the TCXO to be compared with about every 4-seconds. If the TCXO is off frequency during the 4-second interval then sw writes an offset to the TCXO to bring into agreement with the reference. Drift is no different than running the TCXO alone. The improvement is that drift is only allowed a few seconds between corrections which provides the improved accuracy. Stability is still that of the TCXO that is installed. <caveat> This is only my interpretation of the EXREF process - and does not represent Elecraft. 73, Ed Whether you need this accuracy is for you to decide. I like it since I do microwave ham radio where my transverters are phase locked to < 1Hz. It also ensures minimum drift using JT65 on VHF+. Date: Mon, 2 Nov 2015 14:34:50 -0600 From: Doug Hensley <[hidden email]> To: "[hidden email]" <[hidden email]> Subject: [Elecraft] 10 mHZ external reference VS the K3S's optional KTCXO3-1 Message-ID: <[hidden email]> Content-Type: text/plain; charset="iso-8859-1" I've been following the thread on using a 10 mHZ external reference and the prospect seems both affordable and at least initially fun BUT I'd like to ask is it really a practical improvement over Elecraft's available KTCXO3 internal 1ppm reference? Or is this just a way to achieve more accuracy at less cost than the KTCXO3 ? Isn't the K3S better served with its own oscillator? What am I missing here? Thanks, Doug W5JV / AFA6DL 73, Ed - KL7UW http://www.kl7uw.com "Kits made by KL7UW" Dubus Mag business: [hidden email] ______________________________________________________________ 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 Message delivered to [hidden email] |
|
|
In reply to this post by MarcV
I always remember 100K resistors and a 1M resistor was one megohm. I
started with electronics in the mid 50's when transistors were new fangled things with 3 leads connected to a piece of germanium. Even in the 50s, I believe it was recognized that electron flow was from the negative to the positive. I think it was in the late 50s that the military changed to NATO phonetics and Baker's Dog Charlie wasn't Easy in an official capacity. 73, Ken WA8JXM On 11/3/15 1:35 PM, Marc Veeneman wrote: > When I started in the 1950s, we tuned kilocycles and announced Abel, Baker, Charlie, Dog, Easy, Fox. > > A thousand was M, a million was MM, and Greek was a foreign language. > > Does current still flow from + to - in a circuit? If not, then most of my early electronics training was fanciful and my Elmers would be embarrassed were they not SK. ______________________________________________________________ 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 Message delivered to [hidden email] |
«
Return to Elecraft
|
1 view|%1 views
| Free forum by Nabble | Edit this page |