Re: [time-nuts] What’s the BEST crystal?

large pile of nickels to >find out (like > $50M worth), I very much doubt we ever will know the answer. Why would it be so expensive ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never a

Re: [time-nuts] What’s the BEST crystal?

pering gallery" modes come into the picture ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequate

Re: [time-nuts] Quartz crystall and beyond (was: What’s the BEST crystal?)

whispering gallery mode: https://archive.org/details/bstj8-3-493/page/n3/mode/2up -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can

Re: [time-nuts] What’s the BEST crystal?

;have to tool that right up front. [...] Ahh, I misunderstood you then: I thought you meant it as a one-off research project. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attr

Re: [time-nuts] Time-Nutters-- Adding Rubidium to a Thunderbolt...?

You should log the PRS10's PPS timestamps with a computer, I'm sure you will be surprised by what you see. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice

Re: [time-nuts] Time-Nutters-- Adding Rubidium to a Thunderbolt...?

. Only way to slave a PRS-10 from a "good" source, is to do phase-comparison on the 10MHz signal, and after suitable filtering and integration, use that to set the PRS-10 frequency via the serial port. That, on the other hand can give amazing results because of the relatively good X

Re: [time-nuts] Digital Pots, wiper noise and fine tweaking oscillators

ffect and all the other volt-nuts embuggerances. So if you really need _high_ resolution, you are better of leaving the EFC input alone, and putting a high resolution DDS on the output of your OCXO. If you need better phase noise than the DDS, then put a cleanup OCXO with fast analog PLL after the

Re: [time-nuts] Fake new LPRO 101 Rb's on Ebay?

all we know at present that time is sufficient to desinfect 2019-nCov, and to detect any infections. A few specialized infectious agents have the ability to produce "spores" which can survive for *long* periods of time, and then revive on contact with humidity. The best known example is Anth

Re: [time-nuts] The difficulty of low noise measurements

Note that the Maxim RS232 switched-capacitor level conveters are noisy as hell, as are many USB-RS232 adapters. [3] Or check if you can inherit at ton of OPzS from friends in telecom, but pay attention to the hydrogen. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.

Re: [time-nuts] The difficulty of low noise measurements

he latter often think that batteries only need to last "until the diesel kicks in" and that is a very different application. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-ta

Re: [time-nuts] The difficulty of low noise measurements

r (so you don't need a power >supply). You could almost certainly do this for an RS232 output. I >wonder if there's a "no power required" approach for the receiving end. There are people abusing TOSLINK hardware along those lines. -- Poul-Henning Kamp | UNIX since Z

Re: [time-nuts] DAC for OCXO disciplining

ction of oscillator output. And their 14-bit DAC is implemented with TTL driven relays as "a constant-impedance voltage divider". -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-

Re: [time-nuts] The difficulty of low noise measurements

ll such underdimensioned batteries in three years. I tell my customers to dimension UPS batteries for at least one hour. It is be cheaper in batteries in the long run, at it gives their staff a fighting chance if the diesel does not auto-start. -- Poul-Henning Kamp | UNIX since Zilog Zeus

Re: [time-nuts] Power supply for time source concerns

l post: Has anybody ever characterized how much difference it makes to use two different PSU's for heater vs. electronics sides of telecom Rb's ? I'm sure there is a reason why they make it two different pins ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org |

Re: [time-nuts] EFOS B Hydrogren maser arrived

d to read up on this: https://www.lantmateriet.se/contentassets/bbc47979dfef4f338e3c4f8b139da2fb/simplified-transformations-between-itrf2014-and-etrs89-for-maritime-applications.pdf :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

In message <20200309222553.e5b65b79daa2ee195cf13...@kinali.ch>, Attila Kinali writes: >On Mon, 09 Mar 2020 13:44:59 +0000 >"Poul-Henning Kamp" wrote: > >> I'm thinking 24h (to minimize GPS periodicities) frequency measurement >> and adjustment, wit

Re: [time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

e seems to be only two kinds of texts about Kalman: Hard-core math and woo-doo library usage. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can a

Re: [time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

got absolutely no where, because the noise-spectra are not flat or even comparable. Instead started to look at the time distribution of the zero-crossings of the residual low-pass filtered phase error, and that has given me much better results all in all. -- Poul-Henning Kamp | UNIX since Zi

Re: [time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

to optimize it over a couple of years. However, I am pretty certain that we can do better (and faster!) than that, by tuning until we get the right PDF shape for the zero-crossing intervals, if only we know what it should be. My math skills have not been sufficient to derive that. -- Poul-Henning K

Re: [time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

ase adjustment to come with measurement noise and rounding errors ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice wha

Re: [time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

t point on the MVAR plot is very close to 12h, or even better 24h, where the GPS is similarly optimal. Que the HP5065A... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to m

Re: [time-nuts] Ultra Stable Rb

thermal transport mechanisms. There is no reason to think that multi-variable equation has only one flat spot. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what

Re: [time-nuts] Power glitch - Sat morning

ay only have a single phase, and many older apartments also only have a single phase, but I think anything built after 1960 or so have three phases. >If so would there be any benefit to monitoring the frequency of each phase ? No. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p

Re: [time-nuts] Power glitch - Sat morning

ip side, while we have agreed on the voltage, there are 13 different national standards for the plugs and sockets on consumer-stuff... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never at

Re: [time-nuts] Power glitch - Sat morning

e "internal" grid, but that takes us into serious high power EE. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice wh

Re: [time-nuts] power supplies

est Mountain Radio distributors to spread my 24VDC and 12VDC around the lab, highly recommended. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately

[time-nuts] HP5065A reversing the C-field ?

rt it from a frequency normal to geomagnetometer. But if one reversed the C-field, by swapping the wires to the solenoid, and measured the frequency-shift, wouldn't that give a measurement of how good the magnetic shield works ? Has anybody ever tried this ? -- Poul-Henning Kamp | UNIX since

Re: [time-nuts] Pre-averaging Phase Data

was (also) supposed to fix ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.

Re: [time-nuts] Alfred Loomis - an early time nut

'Gee' system. Some years back I saved a copy of JAP's unofficial biography, and when it later disappeared from the web, I put it in a corner of my own homepage: http://phk.freebsd.dk/misc/jack_pierce.html It's a good read. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebs

Re: [time-nuts] Bourns for fine frequency tuning

[1] And the obvious follow-up: Are there any newer designs better suited ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be expl

Re: [time-nuts] measuring timing variation in a web conference.

.. or he was devious enough to have bought a "Vetinari Clock": https://www.instructables.com/id/Lord-Vetinari-Clock/ -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe

Re: [time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

In message <4892914a-b4d6-47a6-9b10-eb18376fc...@n1k.org>, Bob kb8tq writes: >Hi > >In this case the “phase” is phase correction of the output rather than PLL …. And a much smaller phase correction, because it is not trying to also steer the frequency. -- Po

Re: [time-nuts] New Subscriber, DIY GPSDO project (yes, another one)

in a sense putting a PI loop around the PI loop. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _

Re: [time-nuts] Modern HP5065A adjustment ideas

question: Have I understood it right that the control voltage for +/-50 on the fine frequency pot should be +/- 1V for 10544 but only +/- 0.5V for the 10811 ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since

Re: [time-nuts] Quality of timing mode GPS vs survey accuracy

m the OnCore to slowly sneak in on the position which averaged the residuals out. Made no measurable (for me) difference on the timing. http://phk.freebsd.dk/raga/sneak/ -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] Thunderbolt E failing

en subject to a LOT of upward boyancy force. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explai

Re: [time-nuts] Thunderbolt E failing

e-cases, yes. I have hard time seeing anybody dunk their OCXO or Rb... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequate

Re: [time-nuts] distribution amps for 200 MHz

jimlux writes: > For work, I'm looking to distribute 200 MHz to 44 widgets.. > The usual SRS, etc. boxes max out at 100 MHz. Any ideas? A lot of video-production amps would have no trouble with that but they're all 75 Ohm... -- Poul-Henning Kamp | UNIX since Zilog Zeus

Re: [time-nuts] Thunderbolt E failing

ird cinderblock on top, also on its side. You have now increased the thermal impedance by almost two orders of magnitude, and your PLL will be boored. If need be, you can make the central cavity more air-tight by "sealing" between the cinderblocks with a layer of cloth or tissue-p

Re: [time-nuts] Thunderbolt E failing

PLL's are fun, but they require patience on a timescale of years and you need not bother unless you have a *very* benign environment. Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tah

Re: [time-nuts] Need help phase locking with small offset

measure your noise-floor before you trust your data... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by

Re: [time-nuts] Aging 5065A ?

introduces a periodic effect. This stuff is all easy to simulate with a computer. Try simulating a 12 bit Dac and a 14 bit DAC where the LSB is only half the magnitude it should be. If I were trying to build a high-res DDS, I would calibrate the sine-table to the specific DACs imperfections. --

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

or Mills (W3HCF) - but as he's been > retired for some time [...] Dave has been blind for a number of years now. Your best chance might be to catch him on the radio. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | B

Re: [time-nuts] Dead 5065A - Some comments - Some questions... (III)

have been able to make out, both the 137Hz and 5.3x MHz are "mixed" through their amplitude modulation of the DC-bias. My Personal DDS plan is to simply drive the step diode at 59.953... MHz +/- the modulation pattern, and forget entirely about the 5.3x MHz and 137 Hz. -- Poul-Henning

Re: [time-nuts] Dead 5065A - Some comments - Some questions... (III)

rns* than the current sine-wave. (I have no info/opinion on the choice of modulation *frequency*.) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be

Re: [time-nuts] Dead 5065A - Some comments - Some questions...

much any microcontroller with a decent PWM can do the job, which is to output a 10µs pulse evern N cycles of a 5MHz clock signal. I hardcoded the divisor ratio, but one wants to, 16 GPIOs on the microcontroller could read BCD thumbwheels. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.or

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

telcos experiment with all sorts of stuff, fuel-cells (methane & hydrogen), li-batteries, NiFe ("edison") batteries etc. etc. BATTCON papers used to be a god place to read along, but as I mentioned that seems to have lost its luster. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

a unnecessary loss. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ tim

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing list -

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

nd 48VDC are commonly used, and IMO most timing kit is 24VDC. 24VDC is also popular in industrial control settings, for instance: https://www.pulspower.com/products/supplementary-units/dc-ups-and-buffer-modules/ It's expensive and good, but these days almost all of it is switch-mode. -- P

Re: [time-nuts] AGM Batteries

he annual "BATTCON" on the web, but it seems that conference has been "commercialized", and both quality and availability seems to have gone down the drain. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committe

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

ss you want yet another hobby. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

mes for full load. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ t

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

t-circuit currents. If you end up with pre-owned liquid electrolyte batteries ("OPzS") make sure the hydrogen gas can vent safely out of the building. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

converter on a single 12V battery and be done with it. But for a BVA I would choose more expensive batteries over switching noise any day... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Nev

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

have no idea how noisy that is. Advantage: Packages which can be easily soldered by hand. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be exp

Re: [time-nuts] Oscilloquartz BVA has been sold. Thank you all who expressed an interest.

be easier. They are for the same reasons they suffer cyclic use better. But for a float/long-run application, it makes absolutely no difference. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe

Re: [time-nuts] Thunderbolt E failing

resrict airflow. It would have been fun, but I can get the same temperature stability cheaper. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attr

Re: [time-nuts] Microstepper

this one: http://www.rudius.net/oz2m/ngnb/dds.htm as a synthesizer replacement in the HP5065, but your "dual" configuration and the integrated 1GHz "pre-oscillator" would fit that purpose better, so sign me up as interested buyer. -- Poul-Henning Kamp | UNIX since Zil

Re: [time-nuts] SMPS or conventional?

use to control the TEC, needs to understand that there is a 1:3 efficiency difference between the two directions, just slapping a PI(D) on a TEC is guaranteed to kill it. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer |

Re: [time-nuts] SMPS or conventional?

-- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mai

Re: [time-nuts] IEEE 1588 PTP support on raspberry pi 4 compute module

250 pages.) Absent access to such a signal, you have to do the probing entirely in software, which is tricky, expensive, and due to the memory-hierarchy and clock boundaries, very noisy process. So, yeah... Perfect time-nuts project :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus

Re: [time-nuts] WWVB PM Time Questions

400 possibilities have been ruled out and even in horrible S/N we will have found the Hour, Minute and Day in a matter of minutes. Once we're there, we can collect the date bits we still miss. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 Free

Re: [time-nuts] "The Penultimate HP5065 A15"

ike an Aavid 7021, 7022, 7023, or 5510 heatsink. TO-220 (and being indestructible) is why LM317 is my primary candidate. Thanks for the feedback. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.

Re: [time-nuts] "The Penultimate HP5065 A15"

nges. Dont ask me how I know. This is why I suspect the wien-bridge approach may not be a just a homage to the HP200, I think they deliberately wanted to shift the frequencies well north of the 137 Hz. Dithering a PI(D) with a PRNG gets you the same effect, but with wideband noise instead of a sing

Re: [time-nuts] eLORAN in the Antipodes ? (was: Re: eLORAN will be on the air GRI 99600)

stion down here in > Melbourne - a great circle path of some 10,000 mi / 16000 km ? You might be able to pick out the Chinese Loran chains, I believe they're still up. (Use sdr.dh web-sdr's to find out ?) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP sin

Re: [time-nuts] "The Penultimate HP5065 A15"

salignment or intrinsic in the thermostatic regulators. I don't think stabilization on the LM399 level is required, but more stable than the grid voltage would be good. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] "The Penultimate HP5065 A15"

heaters could run of a lower voltage, though +15V may be too low. >A14 If the upstream boards get changed, this likely does as well. >Sort of begs for a $1 MCU and a handful of resistors as a replacement. I was actually pondering doing that on A17. -- Poul-Henning Kamp | UNIX

Re: [time-nuts] "The Penultimate HP5065 A15"

pproach to that is to modulate or dither with a good long PRNG to whiten the noise, and while good in theory, it is not _that_ easy to get right in practice. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since

Re: [time-nuts] eLORAN in the Antipodes ? (was: Re: eLORAN will be on the air GRI 99600)

Gilles Clement writes: > Would’nt 100khz carrier propagate mostly by ground wave (during day time) ? > So following earth curvature ? First: It's not really a 100kHz carrier, it is a 85-115kHz spread-spectrum signal. Second: Yes, and that is exactly the point. -- Poul-Hennin

Re: [time-nuts] eLORAN in the Antipodes ? (was: Re: eLORAN will be on the air GRI 99600)

the timing. When you monitor Loran-C outside the "official" coverage area, the skywave can easily swamp the 3rd positive zero crossing. (The gif above tracks the 3rd negative crossing, because that transmitter is on the "backside" of my loop-antenna.) -- Poul-Henning

Re: [time-nuts] WWVB PM Time Questions

power at all, I did Loran-C time/freq on a Analog Devices Aduc7206: http://phk.freebsd.dk/AducLoran/ And that included a graphical display, (watch the animation.gif :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] "The Penultimate HP5065 A15"

ircuit and thermal protection, so I will probably do it by setting the LM317 voltage with a voltage divider, and then drive the midpoint with an op-amp relative to the LM399 -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] WWVB PM Time Questions

all CW based modulations. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _

Re: [time-nuts] WWVB PM Time Questions

n time constant >could be quite long. I would just use two buffers and decide which one based on the prediction, that way DC-offsets will not cause trouble. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | B

[time-nuts] "The Penultimate HP5065 A15"

it will only works with EXT-DC. I'll post kicad schematic once I get further. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence

Re: [time-nuts] "The Penultimate HP5065 A15"

e a LOT, and still see the same number, if the phase-noise of the other source dominated. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be ex

Re: [time-nuts] "The Penultimate HP5065 A15"

olt-nut :-) > > I have not yet jumped down that rabbit-hole as I am by far not done with > the current one. :) > > I've been looking at the LTZ1000 and one day I may get some. You *really* want the version of it which is packaged in the attractive and *incredibly* useful "HP3458A&quo

Re: [time-nuts] Vibration isolation of quartz oscillators

to spend on your air-con. They are a lot easier to move around though. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice

Re: [time-nuts] Vibration isolation of quartz oscillators

ral the minimum sensitivity is not guaranteed to correspond to any of X/Y/Z. Check if Oscilloquartz have documented the optimal orientation. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe

Re: [time-nuts] Frequency division by 81

attern of 0101... Only 9 of the stages should be driving resistors to the output. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be exp

Re: [time-nuts] Frequency division by 81

> I need to divide the output of an OCXO by a factor D=81 for testing purposes. > So with minimum added phase noise. Two stages of divide by 9 PI-dividers ? http://rubiola.org/pdf-articles/conference/2013-ifcs-Frequency-dividers.pdf -- Poul-Henning Kamp | UNIX

Re: [time-nuts] Vibration isolation of quartz oscillators

and you will find lots of heavy duty stuff. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. _

Re: [time-nuts] Vibration isolation of quartz oscillators

he toroid shape of the inner tube. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained

Re: [time-nuts] FW: HP-5732A operation with no CRT display.

CE,DISPLAY;PRINT", but it is not particularly fast and comes with gratis PCL escapes, but it does work. If you dump the raw measurements, that's precisely what you get, and you will need to do all the processing, math and plotting yourself. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20

Re: [time-nuts] Isolated +20V for lamp supply

tim...@timeok.it writes: > >Corby, > >so why did HP use a coaxial cable for the lamp power? it seems nonsense. Because it generates a LOT of noise, being in essense a VHF/UHF generator. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] x86 CPU Timekeeping and clock generation

ngs of the sort you suggest, but when I benchmarked it, a single brutal 64 bit multiply with a 32bit shift invariably ran faster, had more predictable latency, worked with any frequency the hardware happened to have and did NTP's bidding: http://phk.freebsd.dk/pubs/timecounter.pdf -- Po

Re: [time-nuts] EOL Motorola Oncore Remote Antenna

? > I said lucky because I found some GSynQ parts here in an engineering storage > cabinet that we > can send to you at no charge to revive your unit. Thanks for the offer, but dont bother: I had a spare on hand, and I may still have third one lying around somewhere. -- Poul-Henning Ka

Re: [time-nuts] HP5065a cfield issue

, because it may have a direction different from the C-field solenoid. That also means that even with no frequency shift, a magnetic field could still be present if it is perfectly orthogonal to the C-field solenoid. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] HP5065a cfield issue

Could it be the thermostat circuits have shifted so you run at a different temperature now ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can

Re: [time-nuts] HP 5065 Rb update

e C-field current. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ t

Re: [time-nuts] HP 5065 Rb update

-- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___ time-nuts mai

Re: [time-nuts] EOL Motorola Oncore Remote Antenna

to do maintenance, and see them get hit by a cabinet door swung outward by half an atmosphare over pressure :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to

Re: [time-nuts] HP5065a cfield issue

put the correct frequency and duty-cycle. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence. ___

Re: [time-nuts] HP5065a cfield issue

paul swed writes: > > Also you can kludge in an HP 3325A/B in place of the A1 synthesizer to > > see if that's the problem. 3336 or even 33120 works fine too. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeB

Re: [time-nuts] HP5065a cfield issue

.139 5315085.94 | | 9841 -930.036 5314465.42 | 9397-14.413 5315091.22 | | 9857 -608.295 5314685.32 | 8556 -6.016 5315096.96 | | 9873 -205.467 5314960.64 | 9159 0.013 5315101.08 | +---+-----+ -- Poul-Henning Kamp

[time-nuts] EOL Motorola Oncore Remote Antenna

The first Motorola Oncore Remote antenna I bought has failed after some 20 years of continuous service in Danish climate: http://phk.freebsd.dk/hacks/20201128_EOL_Motorola_Oncore_Remote -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC

Re: [time-nuts] EOL Motorola Oncore Remote Antenna

thing which is guaranteed to work globally is "helium-tight". Anything else needs to be judged against the climate in question, including what kind of aerosols and particulate the wind might bring. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] HP5065a cfield issue

paul swed writes: > Guessing far less than 3 ma. by adding up resistors. More like typical 4 mA: there is a factory select resistor in parallel with the current-setting resistor. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC

Re: [time-nuts] Congratulations to David Allan

do enough self > promotion. Anyway, I'm happy that the powers > that be finally corrected this situation. Maybe the finally recognized his revision of General Relativity ? http://www.allanstime.com/UnifiedFieldTheory/gravity.htm -- Poul-Henning Kamp | UNIX since Zilog Zeus

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