Re: [time-nuts] Time and tide - pendulum clocks and gravity tides

Hi Isn’t there a picture of TVB doing something to that clock? :) Bob > On Oct 19, 2020, at 5:30 PM, Hal Murray wrote: > > Speaking of pendulums... > > BBC: The Clock That Changed the World (BBC History of the World) > https://www.youtube.com/watch?v=T-g27KS0yiY > 29 minutes > > Fantastic p

Re: [time-nuts] Time and tide - pendulum clocks and gravity tides

Speaking of pendulums... BBC: The Clock That Changed the World (BBC History of the World) https://www.youtube.com/watch?v=T-g27KS0yiY 29 minutes Fantastic pictures of of two of Harrison's early pendulum clocks. One has been running for 300 years - no lubrication. -- These are my opinions. I

Re: [time-nuts] SMPS or conventional?

Hi What will the output of the box be used for? If low phase noise is an objective, then one needs to be pretty careful about power supply noise. If low phase noise is not a “need” in this case, then (good) switchers can be used for everything. What’s a “good” switcher? You want one that is reli

[time-nuts] SMPS or conventional?

Hi guys Planning to build my "reference box" with a rubidium & a gpsdo. SMPS will do a good job or the transformer+bridge+capacitor+regulator is best suited for this application? In the "test phase" I've used a switched ps for the rubidium and a conventional for the gpsdo. Thanks Luiz Albert

Re: [time-nuts] DSP-93 Source For WWV/H

John, let me dig around the TAPR site -- we've been reorganizing the files section. On Oct 18, 2020, 9:49 PM, at 9:49 PM, "John C. Westmoreland, P.E." wrote: >Hello Time-Nuts, > >Some of you may already be aware of this web-page/project: > >Precision Radio Clock for Station WWV/H Transmissions

Re: [time-nuts] Time and tide - pendulum clocks and gravity tides

Hi Geoff, Thanks for posting the link. Also nice that the PDF is open access. [1] Besides a large collection of quartz and atomic clocks some of you know that I also play with pendulum clocks. Duncan Agnew's paper is really good and I was very happy that someone with his reputation and backgr

[time-nuts] GPSDO Short Term tests

While my next plot of Droitwich is being generated at this moment, for the meantime here's an analysis of the short term stability of the Leo-Bodnar GPSDO made a couple of years ago. It was done by multiplying the output up to 10GHz and comparing with a caesium derived reference multiplied up. T

[time-nuts] Time and tide - pendulum clocks and gravity tides

Note sure if this has been raised here before, but a new paper by Duncan Agnew is available. "Time and tide: pendulum clocks and gravity tides" https://hgss.copernicus.org/articles/11/215/2020/ It thanks TVB in the "Acknowledgements", so hopefully it is safe to mention it here. I enjoyed readin

Re: [time-nuts] DSP-93 Source For WWV/H

Hello Time Nuts, Indeed Hal! Wow - thanks! Good stuff to go over. And - for those that are new to SDR and I/Q stuff - his docs go over that pretty well. 73's, John AJ6BC On Mon, Oct 19, 2020 at 3:33 AM Hal Murray wrote: > > I wonder if anyone has taken this source and done that already. >

Re: [time-nuts] DSP-93 Source For WWV/H

> I wonder if anyone has taken this source and done that already. The NTP package that comes from http://support.ntp.org/bin/view/Main/SoftwareDownloads has a driver for WWV/H ntpd/refclock_wwvb.c * Audio WWV/H demodulator/decoder * * This driver synchronizes the computer time using data

Re: [time-nuts] DSP-93 Source For WWV/H

Hello Trevor, Yes - I see that now - thanks! Wow, 'c2x assembly - this will be fun. I noticed in his paper(s) (I used the wayback machine) - he has: "The clock should be rewritten in portable C for use on a fast workstation with integrated audio codec." I wonder if anyone has taken this source

[time-nuts] FTAGH: National Instruments DAQCard DIO-24 PCMCIA digital I/O card and cable

Free to a good home: National Instruments DAQCard DIO-24 that I can no longer use. It's a PCMCIA digital I/O card. I no longer have any laptops with PCMCIA slots.  Yours if you want it. It's complete with interface cable and docs.   Pick up in Southlake, TX or for the cost of shipping. I'll ship o

Re: [time-nuts] DSP-93 Source For WWV/H

John C. Westmoreland, P.E. writes: > Some of you may already be aware of this web-page/project: > > Precision Radio Clock for Station WWV/H Transmissions > https://www.eecis.udel.edu/~mills/teaching/eleg403/wwv/wwv_dsp93/ > I've attempted contact with Dr./Professor Mills (W3HCF) - but as

Re: [time-nuts] DSP-93 Source For WWV/H

>Hello Time-Nuts, > >Some of you may already be aware of this web-page/project: > >Precision Radio Clock for Station WWV/H Transmissions >https://www.eecis.udel.edu/~mills/teaching/eleg403/wwv/wwv_dsp93/ >I've attempted contact with Dr./Professor Mills (W3HCF) - but as he's been >retired for >some

Re: [time-nuts] DSP-93 Source For WWV/H

Hello Poul-Henning, I was unaware of Dr./Professor Mills' current condition - thanks for letting me know. 73's, John AJ6BC On Sun, Oct 18, 2020 at 10:46 PM Poul-Henning Kamp wrote: > > John C. Westmoreland, P.E. writes: > > > Some of you may already be aware of this web-page/project: