[time-nuts] Expected 10 MHz offset from a GPSDO?

Hi all, I am starting to dip my toes into time-nuttery after being interested in precise time/position for quite a while (I'm an astronomer IRL). I have acquired a used OCXO and LPRO-101 rubidium, along with a HP5334B (with Option 10) and a HP5370B from ebay and almost done assembling a TADD-2 kit

Re: [time-nuts] Sunrise, solar noon, sunset and the Equation of Time

On Tue, Aug 30, 2016 at 10:07 PM, Mark Sims wrote: > I recently added code to Lady Heather to precisely calculate the sun > position, sunrise/solar noon/sunset times and the Equation of Time... Egad, > what a deep, dark rabbit hole that leads one down. And woe be unto thee

Re: [time-nuts] Normal operating specs of a Morion MV89?

ems unlikely I would get a better one without a lot of trials. Tim > > Bob > > >> On Sep 28, 2016, at 1:38 AM, Tim Lister <lister...@gmail.com> wrote: >> >> On Tue, Sep 20, 2016 at 12:56 PM, Bryan _ <bpl...@outlook.com> wrote: >>> May also want to che

Re: [time-nuts] GPSDO Sigma Tau at large observation times

On Wed, Oct 5, 2016 at 11:01 AM, Tom Van Baak wrote: > Hello again Estanislao, > > Nice set of questions. The short answer is that for a GPSDO, > - The left side of the ADEV plot will show the difference between the quality > of the local oscillator, in your case TCXO vs.

Re: [time-nuts] Normal operating specs of a Morion MV89?

On Tue, Sep 20, 2016 at 12:56 PM, Bryan _ wrote: > May also want to check the output amplitude. If memory serves me correct it > is very common for a capacitor inside this model number to fail. It can be > fixed but requires a torch or a pretty heavy duty soldering iron to

[time-nuts] Normal operating specs of a Morion MV89?

I recently ordered and received what claims to be a 2007 vintage Morion MV89 from ebay (I say claimed as that what the auction item said, but my unit is missing the identifying label on the top and just has '2007 MV89A' written on the side in marker). I've powered it up with a bench power supply

Re: [time-nuts] Normal operating specs of a Morion MV89?

x probe to 800 mVrms >> at 10 MHz your probably not too far off spec. >> >> 100 pF at 10 MHz is 160 Ohms. >> >> On Wed, Sep 28, 2016 at 12:39 PM, Tim Lister <lister...@gmail.com> wrote: >> >>> On Wed, Sep 28, 2016 at 4:14 AM, Bob Camp <kb...@n1k.org> wrote

Re: [time-nuts] Normal operating specs of a Morion MV89?

On Tue, Sep 20, 2016 at 12:56 PM, Bryan _ wrote: > May also want to check the output amplitude. If memory serves me correct it > is very common for a capacitor inside this model number to fail. It can be > fixed but requires a torch or a pretty heavy duty soldering iron to

Re: [time-nuts] Normal operating specs of a Morion MV89?

On Wed, Sep 28, 2016 at 3:30 PM, Scott Stobbe wrote: > You are certainly no where near -40 dBm into 50 ohms as the blog Bryan > posted above. Your setup may have 70-80 pF of load (~220 Ohms), if you also > measured the output voltage with a 10x probe you could work

Re: [time-nuts] Lady Heather Version 5 is now available

On Sat, Dec 10, 2016 at 9:21 AM, wrote: > Thanks for the new version of Lady Heather! I have already downloaded, > compiled it and it is running well on my linux box, but I did have one minor > problem. > I am running Fedora 24 (have not upgraded my Time/Radio PC to

Re: [time-nuts] UCCM GPSDO

On Sun, Dec 4, 2016 at 2:50 PM, Larry McDavid wrote: > Does anyone know the origin of the "UCCM" designation for the Trimble GPSDO > boards recently popular here? > > Is "UCCM" a valid model number, is it an acronym or is it something else? > > I've packaged several of these

Re: [time-nuts] UCCM GPSDO

On Sun, Dec 4, 2016 at 3:04 PM, Bryan _ wrote: > I think the designation "UCCM" actually applies to the Symmetricom GPSDO > boards. Since most of these tend to come salvaged from China, tongue in cheek > I suspect "Unusable, Crushed, Cr_p, Mangled" > > > Do the Trimble units

Re: [time-nuts] Timelab, GPIB-USB-B in a VM

On Mon, Mar 27, 2017 at 2:48 PM, Bob Bownes wrote: > So I'm trying to run timelab in a windows 7 VM with a GPIB-USB-B interface. > > Anyone ever tried such a thing? > > The NI explorer sees the interface but nothing else does. > > Pointers welcome! I believe you have to

Re: [time-nuts] Smart Phone time display accuracy...?

On Thu, Mar 16, 2017 at 2:32 PM, Severin Haas wrote: > The German PTB has a nice widget (https://uhr.ptb.de) to see the actual > time + deviation ("Abweichung"). Can not test this from another location > than UTC+1h, but probably it works at your location. > Does anybody of

Re: [time-nuts] WTB: GPSDO

So it seems the threat of replacement and a bunch of plugging and replugging into different computers has spurred my recalcitrant GPSDO back into life and it is now producing output again... This leaves me with the original problem of low sensitivity but at least I can solve that problem by using

Re: [time-nuts] WTB: GPSDO

On Fri, Mar 10, 2017 at 2:35 PM, Chris Albertson wrote: > A GPSDO is not hard to make. All you need is some way to compare the > phase of two signals, an XOR gate can do that. Then a small $2 > process moves the control voltage on the crystal.I tried one to >

[time-nuts] Papers on timing for lunar laser ranging

Three recent papers from the APOLLO project showed up on my VoxCharta summary of arxiv.org which may be of interest to the time-nuts community. They are to do with improving the precision and absolute calibration of the lunar laser ranging project based at the 3.5m WIYN telescope at Apache Point.

Re: [time-nuts] Papers on timing for lunar laser ranging

On Fri, Jul 7, 2017 at 4:14 PM, jimlux wrote: > On 7/7/17 3:14 PM, Hal Murray wrote: >> >> >> kb...@n1k.org said: >>> >>> Consider that in 1974, I could buy a nice new car for less than what a >>> decent packaged 16 bit DAC cost. Go back into the 1960’s and you are >>> up

Re: [time-nuts] TruePosition GPS Receiver

My TruePosition GPS board arrived yesterday, it seems to be identical to the ones Bob has received down to the same manufacturer of the antistatic sticker over the bag. Given that I had N, BNC and SMA cables already I had hoped I might be in good shape but apparently not so I've had to order 3 new

Re: [time-nuts] GPS splitter

On Fri, Jun 16, 2017 at 4:40 PM, Gregory Beat wrote: > I have reached the point that I need a 4-port splitter for my GPS antenna > (outdoor 5 volt). Any recommendations of models (HP/Symmertricom/Microsemi) > to acquire OR to avoid?? As we recommended to me when I asked a

Re: [time-nuts] Recommendation for cheap GBIP adapter for Linux

On Nov 18, 2017 11:05, "Attila Kinali" wrote: Hi, I have a need for a GBIP adapter that I can use with Linux. It shouldn't be too expensive, but I rather spend a few bucks more for ease of use. Where "ease of use" means I don't have problems with weird drivers on Linux

Re: [time-nuts] ublox NEO-M8T improved by insulated chamber?

On Tue, Nov 7, 2017 at 8:39 PM, Gary E. Miller wrote: > Yo Tom! > > On Tue, 7 Nov 2017 20:16:09 -0800 > "Tom Van Baak" wrote: > >> > Which is small compared to the published GPS time resolution >> > (IS_GPS_200H, page 54) of 90 ns. >> >> Correct. GPS

Re: [time-nuts] Ublox M8T question

On Wed, May 23, 2018 at 5:17 PM, Mark Sims wrote: > I recently got in a Ublox M8T board in from CSGSHOP. The M8T supposedly > outputs raw measurements (carrier phase, pseudorange, doppler) for all the > sat systems it supports, but I am only getting raw measurements for

Re: [time-nuts] nuts about position (cheap receiver)

On Wed, May 2, 2018 at 2:54 PM, Mark Sims wrote: > Well, I processed the Lady Heather .raw capture file from the $24 LEA-5T > through RTKCONV and submitted it to CSRS-PPP and it worked. Using the less > precise instant orbits it says the 95% sigma errors are: lat: 0.169m

Re: [time-nuts] nuts about position

On Thu, Apr 26, 2018 at 12:08 PM, Gary E. Miller wrote: > Scott! > > On Thu, 26 Apr 2018 10:04:54 -0700 > Scott McGrath wrote: > >> Swiftnav has a centimeter accurate multi band receiver RTK-585. Its >> about 600 bucks minus antenna. > > Link? With RTK in

Re: [time-nuts] nuts about position

On Wed, Apr 25, 2018 at 8:38 AM, Tim Lister <lister...@gmail.com> wrote: > On Wed, Apr 25, 2018 at 7:56 AM, Tom Van Baak <t...@leapsecond.com> wrote: >> List -- I had a recent query by a researcher who would like to pinpoint the >> location of his telescope(s) withi

Re: [time-nuts] Team of physicists repeats tvb Project GREAT

On Feb 14, 2018 19:47, "Chris Caudle" wrote: On Wed, February 14, 2018 7:06 pm, jimlux wrote: > At substantially more expense, and with an experimental lattice clock, Does that schematic figure in the paper imply that the "transportable" strontium and ytterbium clocks are

Re: [time-nuts] Introduction & GPSDO Question

On Thu, Apr 19, 2018 at 1:47 PM, Tom Koza wrote: > Hello Everyone, > > My name is Tom and my amateur callsign is WB6FYR, I'm a newcomer to this > group. > > I'm mainly interested in creating a reasonable 10mHz standard for my > various pieces of test equipment here at home. To

Re: [time-nuts] nuts about position

On Wed, Apr 25, 2018 at 7:56 AM, Tom Van Baak wrote: > List -- I had a recent query by a researcher who would like to pinpoint the > location of his telescope(s) within 0.3 meters. Also (he must be a true > scientist) he wants to do this on-the-cheap. He may have timing