Re: [time-nuts] World's most precise.... wall clock

> In tboltmon, the signal "strength" indications are displayed in units > called 'AMU' for which I've been unable to find a definition. Amplitude Measurement Units? There was a discussion about this some years ago. The TBolt (and other Trimble receivers) give a user the choice of reported GPS

Re: [time-nuts] World's most precise.... wall clock

Sent from my iPhone > On 10 Mar 2021, at 15:54, Dana > > I have convinced myself that the PPS output from my Tbolt is derived from > the produced > 10 MHz output, because if I trigger an o'scope from the PPS output, the 10 > MHz sinewave > shows very little time jitter, perhaps 1 or 2 nsec.

Re: [time-nuts] World's most precise.... wall clock

Hi, On 2021-03-11 00:38, Bob kb8tq wrote: > Hi > >> On Mar 10, 2021, at 4:57 PM, Magnus Danielson wrote: >> >> Hi, >> >> On 2021-03-10 17:04, Bob kb8tq wrote: >>> Hi >>> On Mar 10, 2021, at 9:39 AM, Charlie wrote: Bob- As a rank amateur e astronomer, I am a lurker. I

Re: [time-nuts] World's most precise.... wall clock

Hi > On Mar 10, 2021, at 4:57 PM, Magnus Danielson wrote: > > Hi, > > On 2021-03-10 17:04, Bob kb8tq wrote: >> Hi >> >>> On Mar 10, 2021, at 9:39 AM, Charlie wrote: >>> >>> Bob- >>> >>> As a rank amateur e astronomer, I am a lurker. I am amazed at what I have >>> learned here. I know that

Re: [time-nuts] World's most precise.... wall clock

Hi, On 2021-03-10 17:04, Bob kb8tq wrote: > Hi > >> On Mar 10, 2021, at 9:39 AM, Charlie wrote: >> >> Bob- >> >> As a rank amateur e astronomer, I am a lurker. I am amazed at what I have >> learned here. I know that there are differences between the meaning of >> precision and accuracy, but

Re: [time-nuts] World's most precise.... wall clock

6CFH > > > > > > > > > > > > > -Original Message- > From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of Bob > kb8tq > Sent: Wednesday, March 10, 2021 5:24 AM > To: Discussion of precise time and frequency measu

Re: [time-nuts] World's most precise.... wall clock

I was thinking about the discussion on synchronizing a grandfather clock using a magnet and coil.   Most methods for doing this use an external power supply or a battery. What about powering the synchronizing circuit from energy harvested from the pendulum.   Consider that you can get a quartz

Re: [time-nuts] World's most precise.... wall clock

-Original Message- From: time-nuts [mailto:time-nuts-boun...@lists.febo.com] On Behalf Of Bob kb8tq Sent: Wednesday, March 10, 2021 5:24 AM To: Discussion of precise time and frequency measurement Cc: hmur...@megapathdsl.net Subject: Re: [time-nuts] World's most precise wall clock

Re: [time-nuts] World's most precise.... wall clock

Hal, The older (and probably the newer models, too) Trimble Thunderbolt GPSDOs have a user-adjustable time constant accessible via the serial port using a program like "Tboltmon.exe" (from Trimble). I suspect that "Lady Heather" may also do this. I am fortunate in owning a still functioning

Re: [time-nuts] World's most precise.... wall clock

Hi, On 2021-03-10 14:23, Bob kb8tq wrote: > Hi > >> On Mar 10, 2021, at 6:04 AM, Hal Murray wrote: >> >> >> kb...@n1k.org said: >>> The gotcha here is that if you want accurate *time*, you are better off >>> using >>> the sawtooth corrected output from a (good) GPS module rather than a GPSDO.

Re: [time-nuts] World's most precise.... wall clock

Hi > On Mar 10, 2021, at 6:04 AM, Hal Murray wrote: > > > kb...@n1k.org said: >> The gotcha here is that if you want accurate *time*, you are better off using >> the sawtooth corrected output from a (good) GPS module rather than a GPSDO. > > Why is that? The controller gets in the way. If

Re: [time-nuts] World's most precise.... wall clock

kb...@n1k.org said: > The gotcha here is that if you want accurate *time*, you are better off using > the sawtooth corrected output from a (good) GPS module rather than a GPSDO. Why is that? I would have guessed that a GPSDO would average over many GPS pulses thus reducing the noise. Is it

Re: [time-nuts] World's most precise.... wall clock

Hi The gotcha here is that if you want accurate *time*, you are better off using the sawtooth corrected output from a (good) GPS module rather than a GPSDO. Bob > On Mar 3, 2021, at 6:20 PM, djl wrote: > > Hi John: What's the cost of the CSAC GPSDO? I'd ask directly, but the exact > device

Re: [time-nuts] World's most precise.... wall clock

Hi John: What's the cost of the CSAC GPSDO? I'd ask directly, but the exact device specification seems a bit murky. Thanks On 2021-03-03 10:34, John Sloan wrote: I’ve built several small home-brew NTP servers using a Raspberry Pi, a GPS receiver, and an LCD display. Most of them are desk

Re: [time-nuts] World's most precise.... wall clock

This might be desirable. https://www.ebay.com/itm/THE-AMATEUR-SCIENTIST-ON-CD-ROM-LATEST-EDITION-VERSION-4-M2071-/112117678275 On Wed, Mar 3, 2021 at 4:19 PM Chris Caudle <6807.ch...@pop.powweb.com> wrote: > > > On Tue, 02 Mar 2021 22:42:45 -0800 > > Hal Murray wrote: > > > >> The basic idea is

Re: [time-nuts] World's most precise.... wall clock

On Tue, 02 Mar 2021 22:42:45 -0800 Hal Murray wrote: The basic idea is to mount a magnet on a stiff wire so that it sticks out to the side of the pendulum arm, then mount a coil so the magnet will swing through it. Now pulse the coil to get the desired results. On 2021-03-03 02:54, Attila

Re: [time-nuts] World's most precise.... wall clock

I’ve built several small home-brew NTP servers using a Raspberry Pi, a GPS receiver, and an LCD display. Most of them are desk clocks. My favorite one (and the biggest money sink) is a mantle clock in my living room that incorporates a chip-scale cesium “atomic clock”. Photo:

Re: [time-nuts] World's most precise.... wall clock

Hi! I found a copy at Edésio On Tue, Mar 02, 2021 at 10:42:45PM -0800, Hal Murray wrote: > > Maybe one day I'll make this work with a grandfather clock. > > Many years ago, Scientific American had an article describing adding

Re: [time-nuts] World's most precise.... wall clock

On Tue, 02 Mar 2021 22:42:45 -0800 Hal Murray wrote: > The basic idea is to mount a magnet on a stiff wire so that it sticks out to > the side of the pendulum arm, then mount a coil so the magnet will swing > through it. Now pulse the coil to get the desired results. This is basically

Re: [time-nuts] World's most precise.... wall clock

> Maybe one day I'll make this work with a grandfather clock. Many years ago, Scientific American had an article describing adding a magnet to the pendulum and the circuitry to drive it. The basic idea is to mount a magnet on a stiff wire so that it sticks out to the side of the pendulum arm,

Re: [time-nuts] World's most precise.... wall clock

displays also; just add "nixie" to the Google search string. Good luck Dave M From: "Eamonn Nugent" To: time-nuts@lists.febo.com Sent: Tuesday, March 2, 2021 4:38:24 PM Subject: [time-nuts] World's most precise wall clock Hi! I have a perhaps silly question. I want

Re: [time-nuts] World's most precise.... wall clock

Eamonn, Here are a couple of ideas for you: 1) You may find some GPS / NTP / 1PPS / 10 MHz precise time friendly professional clocks at: https://www.masterclock.com/ 2) If you have a 50/60 Hz mains wall clock you can always use this trick: http://leapsecond.com/pages/atomic-nixie/ 3) You

Re: [time-nuts] World's most precise.... wall clock

On 3/2/21 4:32 PM, ed breya wrote: If you can open it up and get at and identify the crystal, you can synthesize its ideal frequency from a GPSDO output, then run it in there in place of the crystal. I did this for a 24hr Mars clock using a 3325 to generate 31947.2745 Hz

Re: [time-nuts] World's most precise.... wall clock

If you can open it up and get at and identify the crystal, you can synthesize its ideal frequency from a GPSDO output, then run it in there in place of the crystal. Ed ___ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to

Re: [time-nuts] World's most precise.... wall clock

Hi, I had same question several years ago. You're gonna have to roll your own. Look here On Tue, 2 Mar 2021 17:38:24 -0500, Eamonn Nugent wrote: >Hi! >I have a perhaps silly question. I want to take an inferior medium (our

[time-nuts] World's most precise.... wall clock

Hi! I have a perhaps silly question. I want to take an inferior medium (our eyes) and give it something attractively precise to look at. Is there such a thing as a digital (wall) clock with a 1PPS/10MHz/etc. input? I see that some clocks have GPS antenna inputs, but I want to take a GPSDO and