Re: [time-nuts] ✘NEO-M8N vs. NEO-M8T

On Mon, May 21, 2018 at 5:54 PM, Gary E. Miller wrote: > Also, how does that get me to the gola of a good PPS to feed into the > Linux PPS kernel module? I doubt Linux would accept a patch to put > gpsd, and more, into the kernel to read GPS and adjust the PPS. Considering that

Re: [time-nuts] Furuno GT-8031 breakout board

Hi Bob, If you do a group buy of GT-8736 I'm game for 10. On Thu, Feb 15, 2018 at 6:55 PM, Bob Darlington wrote: > I bought some of the Furuno GT-8736 boards for $35 a pop, qty 1 (or 2 as > was the case). And was quoted at $26.91 a pop if I buy 100. If there's >

Re: [time-nuts] Why discipline Rubidium oscillator?

On Mon, Nov 20, 2017 at 8:28 PM, Jerry Hancock wrote: > Bob, I was referring to the rubidium standard of 6834682610.904 Hz. For some > reason I thought it was closer to 9Ghz. > > I assume then rubidium standards oscillate (if that is the correct term) > somewhere around that

[time-nuts] Novatel Dual frequency GNSS receivers on ebay

There is an ebay listing for "Novatel GPS-702-GG with SPAN-CPT Single Enclosure GNSS/INS Receiver + Cable" with a fairly large number available. This is a Novatel OEM628 dual frequency receiver (supports GPS, Glonass, SBAS, apparently including L1C and L2C), plus a three fiber ring gyros (with

[time-nuts] The Witching Hour; short fiction that will likely amuse time-nuts

Found on the web: http://slatestarcodex.com/2013/11/03/the-witching-hour/ ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.

Re: [time-nuts] Optical Cesium or maybe Cesium "light"!

On Sat, Mar 18, 2017 at 2:48 AM, wrote: > Looks like Oscilloquartz is getting ready to sell this commercially! http://www.chronos.co.uk/files/pdfs/itsf/2015/day2/1410_High_performance_optically-pumped_cesium_beam_clock-PBerthoud-Oscilloquartz.pdf Two year old deck with a fair

Re: [time-nuts] hm H Maser

On Wed, Jan 11, 2017 at 12:25 AM, Bob kb8tq wrote: > I have a pile of stuff. You have a pile of stuff. Others each have their pile > of stuff. Doing > a design that works only with my pile is possible. Doing a design that works > with my pile [...] > You have to do it with a

Re: [time-nuts] Line Voltage - USA

On Mon, Jan 2, 2017 at 4:49 AM, Bill Byrom wrote: > Most US homes and small businesses are powered by what is commonly > called a "split-phase" 240 V feed. The final distribution system > transformer has a 240 V center-tapped secondary. The center tap is > grounded, and three

Re: [time-nuts] Google public NTP service

On Wed, Nov 30, 2016 at 2:21 PM, Michael Rothwell wrote: > ... was just announced. > https://cloudplatform.googleblog.com/2016/11/making-every-leap-second-count-with-our-new-public-NTP-servers.html?m=1 Obvious outcome is obvious. Leap smear prevented faults between google

[time-nuts] Sapphire whispering gallery mode masers?

The recent mention of WGM sapphire oscillators and recent threads about time-nut constructable secondary frequency standards reminded me of a paper I ran into a while back about a WGM maser. The mechanical of the device were similar to an ordinary WGM oscillator: cryocooled sapphire crystal in a

Re: [time-nuts] Tbolt issues

On Fri, Sep 2, 2016 at 12:51 AM, Charles Steinmetz wrote: > Now shorten the observation time to 20nS. We see 1/5 of a complete cycle > (72 degrees, 0.4 pi radians) of the wave. No matter which particular 72 > degrees we see, we simply don't have enough information to

[time-nuts] Ashtech Z-12 firmware?

I recently picked up a couple non-functional Ashtech Z-12 receivers with the external frequency input (these appear to PLL an internal TCXO; I understand there are other models where they replace the TCXO completely). I was hoping to use them both better data sources for common view time transfer

Re: [time-nuts] NUT4NT: Four-channel All-frequency GNSS RF-to-Bits

On Sat, Aug 13, 2016 at 11:53 PM, Bob Camp wrote: > Hi > > It’s not real clear what the second chip on the board does. If it is just a > bit to Ethernet converter > then you are dealing with 2 bit data out of each of the four channels. You > aren’t just doing tracking > in that

Re: [time-nuts] NUT4NT: Four-channel All-frequency GNSS RF-to-Bits

On Thu, Aug 4, 2016 at 11:08 PM, Daniel Mendes wrote: > > A new interesting toy soon to be crowdsourced: > > https://www.crowdsupply.com/amungo-navigation/nut4nt A shame, it looks like it can be externally clocked, but I don't see a way to get in and measure a PPS signal.

Re: [time-nuts] Leap second to be introduced at midnight UTC December 31 this year

On Thu, Jul 21, 2016 at 5:27 PM, Tom Van Baak wrote: > Time to mention this again... > > If we adopted the LSEM (Leap Second Every Month) model then none of this > would be a problem. The idea is not to decide *if* there will be leap second, > but to force every month to

Re: [time-nuts] LEA-M8T

On Fri, Apr 8, 2016 at 12:06 AM, Tom Van Baak wrote: > Meanwhile it would not surprise me if each GNSS system gives a slightly > different position and a slightly different time than GPS does. One could easily imagine a system that when signals from both constellations were

[time-nuts] Springer textbooks >10 years old now available for download as PDF at no cost

The Quantum Beat http://link.springer.com/book/10.1007/978-1-4757-2923-8 Frequency Standards and Metrology http://link.springer.com/book/10.1007/978-3-642-74501-0 Frequency Measurement and Control http://link.springer.com/book/10.1007/3-540-44991-4 (and, many many other books on control theory,

Re: [time-nuts] GPS Disciplined TCXO

On Fri, Oct 23, 2015 at 11:08 PM, Nick Sayer via time-nuts <time-nuts@febo.com> wrote: > >> On Oct 23, 2015, at 2:09 PM, Gregory Maxwell <gmaxw...@gmail.com> wrote: >> >> On Tue, Oct 20, 2015 at 8:53 PM, Bryan _ <bpl...@outlook.com> wrote: >>> Saw t

Re: [time-nuts] GPS Disciplined TCXO

On Tue, Oct 20, 2015 at 8:53 PM, Bryan _ wrote: > Saw this on the Hackaday site if anyone is interested. > https://hackaday.io/project/6872-gps-disciplined-tcxo Will this design that uses the output of the DAC directly not run into problems with non-monotonicity and/or

Re: [time-nuts] KS-24361 REF-0 standalone

On Fri, Aug 7, 2015 at 6:06 PM, paul swed paulsw...@gmail.com wrote: Looking forward to the notes. Yes it could be fairly simple if what ref 0 wants is a string that essentially says the system is fixed with 3 d accuracy. Perhaps after that the ref 0 makes no checks other then the string keeps

Re: [time-nuts] End Of The World

On Wed, Jul 1, 2015 at 1:03 AM, Bob Camp kb...@n1k.org wrote: Hi So are we all still here? Any portion of the group blasted into non-existance by the leap second please speak up :) === Any observations of anomalous behavior yet? I was eagerly connecting to various things to watch for

Re: [time-nuts] Using CPLD/FPGA or similar for frequency

On Tue, Jun 9, 2015 at 11:40 AM, Alan Ambrose alan.ambr...@anagram.net wrote: How about a 1pS resolution TIC? :) Or a 12 digit frequency counter? :) :) It's not a proper time-nut project unless there's a nutty element... Well, how complex? Front end with a fast ADC and make a DSP DMTD

Re: [time-nuts] Current state of optical clocks and the definition of the second

On Tue, Jan 13, 2015 at 5:46 PM, Dr. David Kirkby (Kirkby Microwave Ltd) drkir...@kirkbymicrowave.co.uk wrote: I had a brief read. Equation 1 made me wonder what could be achieved with a cheap HeNe laser. It should be fairly easy to mix a couple of See Sams Laser Faq section on stabalized HeNe

Re: [time-nuts] Current state of optical clocks and the definition of the second

On Mon, Jan 12, 2015 at 12:34 PM, Attila Kinali att...@kinali.ch wrote: I just stumbled over this [1] nice article by Fritz Riehle that might be of interest to others as well. I've seen less discussion of non-atomic stable optical oscillators. Most (all?) of these optical atomic standards are

Re: [time-nuts] June 30 2015 leap second

On Fri, Jan 9, 2015 at 3:21 PM, Martin Burnicki martin.burni...@burnicki.net wrote: Systems which are simply time clients can receive the leap second warning via the usual protocols like NTP or PTP/IEEE1588. Indeed, they can. Even when there hasn't been a leap-second. Practically all internet

Re: [time-nuts] Fwd: CGSIC: FW: New NANU 2014090

On Wed, Dec 17, 2014 at 12:01 AM, Jim Lux jim...@earthlink.net wrote: On 12/16/14, 3:36 PM, Magnus Danielson wrote: what about one of the software receivers? I would think that making L2 and L5 filters isn't that tough, so all you need is the back end. I'm pretty sure GNSS-SDRLIB supports

Re: [time-nuts] 58503a and Yixunhk

On Sun, Dec 14, 2014 at 1:38 AM, Adrian rfn...@arcor.de wrote: Same here. I have a Z3805A from this vendor that works flawlessly, and I know of other people that purchased from him without any problems. To call it a cam when a HP unit comes with a remanufactured box is quite a harsh

Re: [time-nuts] gravity, space and time

On Fri, Dec 12, 2014 at 8:42 PM, folkert folk...@vanheusden.com wrote: Hi, If I understood it well, we should occasionally encounter gravitational waves going through, well, the whole galaxy. As time and space are intertwined, those ripples may be measured somehow I guess. Isn't this that we

Re: [time-nuts] Beaglebone NTP server

On Wed, Dec 10, 2014 at 9:58 PM, Brian Lloyd br...@lloyd.aero wrote: Well, I am hoping to get to the point where the path to using the BBB as an NTP server using the PRU for more precise timing, and using the LTE-lite to provide the 1pps and time data. Of course, the LTE-lite can also provide

Re: [time-nuts] Did a member of time-nuts buy this?

On Sun, Dec 7, 2014 at 7:03 PM, Bob Camp kb...@n1k.org wrote: Of the $20K to $30K that a new tube costs, I doubt the material and basic assembly adds up to over $5K. The rest of the cost is the final assembly / test / yield / re-test / tooling / labor. That’s doing them in as high a volume

[time-nuts] Did a member of time-nuts buy this?

Bob Camp wrote: Unless you are making a GPS receiver from scratch (which you might be), there is a certain “trust factor” that comes into using a GPS for timing. Since you can’t play with the firmware, you trust that the guy who wrote it did a good job. As compared to internet facing