Re: [time-nuts] GPSDO and oscillator steering - EFC vs DDS schemes?

with pi before putting it >into their time-plan. :) Interesting. In computing we make a random guess at the duration. The manager is supposed to multiply the numeric part by two and shift the unit to the next higher one. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.or

Re: [time-nuts] GPSDO and oscillator steering - EFC vs DDS schemes?

be close-in multiples, so coping with the spurs becomes non-trivial. That basically means that you need 50% higher DDS and DAC resolution than everybody else in the market an suddenly it isn't cheap any more. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] Hydrogen maser frequency jumps

In message , Azelio Boriani writes: >How are related the three locations' jumps? >Do they occur at the same time? If so, don't miss the Nobel Prize potential :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 F

Re: [time-nuts] Hydrogen maser frequency jumps

bvious thing to look at is a weak input signal on the input side of that divider. -- 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

[time-nuts] Need tiny 5MHz 10x amplifier

ince space is a bit tight, I've been trying to find something like a "x10 self-biasing amplifier" but without luck. Any good ideas ? -- 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] HP 5065A battery pack

ven with the rather suboptimal charging circuit (not atypical for its vintage) they'll probably survive for a number of years just fine. -- 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] HP 5065A battery pack

kit which you lug around, VRLA is the way to go for standby. -- 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] HP5065A status so far

and the Integrator can be improved, but I have no measurement results there yet. The blow by blow can be found here: http://phk.freebsd.dk/hacks/HP5065A/index.html Poul-Henning -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD commit

Re: [time-nuts] When NTP goes wrong...

exploit this or any other spoofing attack. This is where it would really be helpful if people read the paper, because they spend considerable text sorting through what requires you to be in-band and what doesn't. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] When NTP goes wrong...

net to be negligible. That's because the standardized way of doing it doesn't really work. >> The only real cure is to have your own NTP servers. >> >Which then of course must not rely on external sources for their time, Obviously. There is no free lunch. -- Poul-Henn

Re: [time-nuts] When NTP goes wrong...

cure is to have your own NTP servers. -- 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

[time-nuts] Useful gadgets for DC power

ey don't respond to email :-( -- 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] UPS for my time rack

k.freebsd.dk/hacks/HP5065A/20150930_dcdc/index.html >Umm, around here, at least for ham radio operators, it seems many >standardize now on PowerPole connectors for 12V DC. They're quite neat, but I wish there were something a little less heavy-duty for the 1-2 Amp range. -- Poul-Henning

Re: [time-nuts] UPS for my time rack

it to go anywhere ever. At the same time USB has come up with 100W power concept which is not compatible, since IEEE uses CANbus and different connectors. I've not heard any rumours that China man nail this one. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] Symmetricom 58534A-H01, NOS surplus (eBay)

7 for the cable. Do think about lightning protection, if nothing else, tie a knot in the cable right outside the hole into the building. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Neve

Re: [time-nuts] UPS for my time rack

y Battery, generator and UPS failure, in that order. Many sites simply have lower uptime after they install UPS systems. -- 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 ma

Re: [time-nuts] UPS for my time rack

ever look back. Presenty the load is 6.7A @ 24V, and that powers my ADSL lines, firewalls (soekris), home server (ITX with mini-box.com PSU), emergency lights (LED strips), GPS, GPSDO, HP5065 etc. etc. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP sinc

Re: [time-nuts] More HP5065 experiments

nd a processor, a lot of servo-loop algorithms become viable. -- 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 adeq

Re: [time-nuts] More HP5065 experiments

asurement of the lamp supply sensitivity was mainly intended to provide data on the required level of power supply stability. -- 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] More HP5065 experiments

hing about design choices etc. -- 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] More HP5065 experiments

In message <5607d3b0.80...@rubidium.dyndns.org>, Magnus Danielson writes: >You should be able to servo the intensity using the DC intensity level >detected by the photodetector. That would require a way to steer the intensity. I can try to measure that at some point. --

[time-nuts] More HP5065 experiments

Discovery of the day: The voltage supplied to the Rb87 lamp changes the frequency on the order of 1.5e-11 per volt. I have no idea why... http://phk.freebsd.dk/hacks/HP5065A/index.html -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956

Re: [time-nuts] teensy as time capture device

t, because the 33120 will generate a sine and run it through a zero-detector. You get much better performance by defining a ARB function which is a square. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since

[time-nuts] HP5065 integrator PCB

competency.) -- 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-nu

Re: [time-nuts] HP5065A C-field current voltage mod

My HP5065 adventures continue... http://phk.freebsd.dk/hacks/HP5065A/20150908_a15/index.html -- 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] HP5065A C-field current voltage mod

sheet specified 2.5 uV noise. The REF 012A >specifies 5 uVnoise. The first two are around 50 cents from Mouser.  >The REF102A is about 10X more. Stuff like that seldom happen by chance :-) TL431 is amazing and very versatile, but it does not look like the right solution to me in this case.

Re: [time-nuts] HP5065A C-field current voltage mod

h the Fluke 732+resistor C-field driver, there is no sign of any drift yet. So yes, it may not be the RVFR that's drifting (most) and that just makes this game even more fun... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD

Re: [time-nuts] HP5065A C-field current voltage mod

In message <89828.1441376...@critter.freebsd.dk>, "Poul-Henning Kamp" writes: >I actually have some calculations relevant to this, I'll write them >up on my homepage when I have a second. Here: http://phk.freebsd.dk/hacks/HP5065A/20150904_math I&#x

Re: [time-nuts] HP5065A C-field current voltage mod

arts. I actually have some calculations relevant to this, I'll write them up on my homepage when I have a second. The short version is that voltage reference noise above 5PPM will be a limiting factor on performance. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] Subject: Subject: Re: HP5065A C-field current voltage mod

erature to change accordingly. More details here: http://phk.freebsd.dk/hacks/HP5065A/20150903_psu/ -- 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] HP 5730 data polling technique?

can use the MD2 mode, where measurements only start when the computer sends "MRM" to the counter. I usually use the former method because I get more precise pacing of the measurements (I feed EXT ARM from a HP33120). -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd

Re: [time-nuts] Subject: Re: HP5065A C-field current is temperature sensitive

In message <145271941.122608.1441164033464.javamail.ya...@mail.yahoo.com>, Perr y Sandeen via time-nuts writes: >A possible solution might be touse two of the TL431 programmable >shunt regulators. That would be worse than what is in my 5065 now. -- Poul-Henning Kamp

Re: [time-nuts] HP CS oven curious question

than the modulationfrequency so that it filters out. -- 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 inc

Re: [time-nuts] HP5065A C-field current is temperature sensitive

Replace A15R10 and A15R11 with a combination of <5PPM resistors having that value. Ie: if your A15CR5 voltage is 7.9 Volt, you should remove R10 and R11, and put a 600 Ohm resistor there instead. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org |

Re: [time-nuts] HP5065A C-field current is temperature sensitive

ke the >741 or something (irony may have been used). Yes, that is absolutely the plan. The integrator and AC-amplifier in the HP5065 gets upgraded to chip op-amps in later revs, but this one does not. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org |

Re: [time-nuts] HP5065A C-field current is temperature sensitive

1 with something of that value and better than 5PPM tempco. -- 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] HP5065A C-field current is temperature sensitive

ob done. It's not just the swing, it's also the shape of the curve: http://phk.freebsd.dk/hacks/HP5065A/20150828_c_pot/index.html If it were just the range things would be a lot simpler. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP

Re: [time-nuts] HP5065A C-field current is temperature sensitive

onent is responsible for the huge tempco, but it is not the C-field pot. There's a few PPM there but not that many. -- 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 mali

Re: [time-nuts] HP5065A C-field current is temperature sensitive

27;m doing right now: C-field driven by Fluke 732A through 2.5k resistor. -- 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] HP5065A C-field current is temperature sensitive

nt-sensing resistors R10||R11 have a very high temp-co. Getting closer... -- 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 in

Re: [time-nuts] Running voltages through MVAR (In re: HP5065)

averaging inside of MDEV ruins interesting noise periodics I generally hunt periodics with FFTs, but yes, ADEV is useful for the sort of "almost has a stable frequency" like HVAC's turning on/off etc. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

[time-nuts] Running voltages through MVAR (In re: HP5065)

he C-field current of my HP5065 is unstable: http://phk.freebsd.dk/hacks/HP5065A/20150822_mvar/index.html I'm not done collecting data for the resulting effect on the HP5065 performance, but so far it looks like the MVAR floor is half of what it used to be. -- Poul-Henning Kamp | U

Re: [time-nuts] HP5065A C-field current is temperature sensitive

tempco current-limiting series resistor. Anybody want to bet what *that* will do to the MVAR floor ? I'll write this up on my web-pages once I have more data. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer |

Re: [time-nuts] HP5065A C-field current is temperature sensitive

urrent. The 7.5 mA optimum is from a much later data-sheet, and may be for a particular "high performance" variant of the 1N938, so there is no guarantee that there even is a zero-tempco current for the one in my HP5065. Either way, fixing the zeners tempco is only half of the solution, it

Re: [time-nuts] HP5065A C-field current is temperature sensitive

://phk.freebsd.dk/hacks/hp5065a_temp/index.html -- 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] GPS outage? 19:00-2100 UTC Tue

r? > >Was it local interference, or something at the GPS level? Nothing on my side of the planet. Most likely a "White Van Man" who doesn't want the boss to track his use of the company car outside business-hours. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...

[time-nuts] HP5065A C-field current is temperature sensitive

ement. If A15CR5 is the culprit, the next obvious step is to change A15R7 to 1500 Ohm, and see if that improves stability. Another obvious experiment is to drive the C-field with a very stable external supply, and see what that does for the MVAR. -- Poul-Henning Kamp | UNIX since Zilog Zeus

[time-nuts] The Manuals Plus remains are being rescued

http://ascii.textfiles.com/archives/4683 http://ascii.textfiles.com/archives/4695 http://ascii.textfiles.com/archives/4683 -- 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] HP 10811-60165 Double Oven

In message <6B73B186D5BB46E497D773717A4A03D1@pc52>, "Tom Van Baak" writes: >Wonderfully, if you google for: > >HP 10811-60165 pinouts > >you get a bunch of time-nuts pages with the info you want. Isn't it high time we create a time-nuts wiki

Re: [time-nuts] HP10811 vs 00105 OCXO

arge mechanical shocks. This is very relevant for 2nd-hand equipment, and doubly so if it has been through the E-waste circuit via China. -- 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] reception of loran C from Sylt

where you live. It can be anything from a LED-lamp over a laptop to natural gas burner. -- 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

[time-nuts] Speaking of HP5065 repair/improvement

x27;t fix or tune your 5065 for you. If you want your 5065 in competent hands, send it to Corby. -- 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] Modified Allan Deviation and counter averaging

anageable to record an average of 1000 measurements once per second, than 1000 measurements every second. >For any other form of random >noise and for the systematic noise, you alter the total filtering >behavior [...] Agreed. -- Poul-Henning Kamp | UNIX since Zilog Zeus

Re: [time-nuts] Data Collection for Allan Deviation

ple of your basic sampling frequency (1Hz) -- 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] Data Collection for Allan Deviation

7;m measuring, I can have no expectation of a well behaved noise from the triggers. The "noise" you saw is probably exactly that: Overly optimistic results if you clock the counter from one of the DUTs -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org |

Re: [time-nuts] Modified Allan Deviation and counter averaging

noise. But I have not found any references to this "optimization" anywhere and either I'm doing something wrong, or I'm doing something else wrong. I'd like to know which it is :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP si

Re: [time-nuts] Data Collection for Allan Deviation

o calculate the MVAR. The Lady Heather program should be able to do it with data collected this way. -- 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] Modified Allan Deviation and counter averaging

ut 1.0e-11 frequency error on average (RMS average?)" Close: To a first approximation MVAR is the standard-deviation of the frequency, as a function of the time-interval you measure the frequency over. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/

Re: [time-nuts] Modified Allan Deviation and counter averaging

>If you look at the attached plot there are four datasets. And of course... Here it is: -- 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] Modified Allan Deviation and counter averaging

100 Hz raw data file which is ny "new" HP5065 against an GPSDO. -- 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] Austron 2000C, anyone?

it has been modified for 4-digit GRIs. -- 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

[time-nuts] Modified Allan Deviation and counter averaging

ocessing. Am I overlooking anything ? -- 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] Flashback to 1988 (Austron Catalog)

ans. Can we persuade you to all that stuff and uploade it to KO4BB or similar ? I'd love to get a chance to read it... -- 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 t

Re: [time-nuts] Firmware and antenna for Stanford Research FS700 Loran C frequency standard

ich allows you to find the right zero-crossing. -- 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 incompete

Re: [time-nuts] Firmware and antenna for Stanford Research FS700 Loran C frequency standard

he loop is a function of the area. I think they're barking up another tree: The number of turns you can make is inversely proportional to cross-section of the wire, so given a fixed mass of conductor, you can trade current for voltage by the number of turns. -- Poul-Henning Kamp |

Re: [time-nuts] Firmware and antenna for Stanford Research FS700 Loran C frequency standard

asures impedance as low as 100 kHz. 100 kHz is practically audio, impedances hardly matter: The reflections have wavelengths measured in km. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Neve

Re: [time-nuts] Firmware and antenna for Stanford Research FS700 Loran C frequency standard

nna Amplifiers" document and it drags in signals from 4kHz to well north of 150Mhz. -- 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

Re: [time-nuts] Loran C returning to a station near you...

; The pulses themselves are entirely contained inside the allocated >> frequency band. -- 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] Firmware and antenna for Stanford Research FS700 Loran C frequency standard

In message <55a68425.6020...@kirkbymicrowave.co.uk>, "Dr. David Kirkby - Kirkby Microwave Ltd " writes: >What's the best sort of antenna for these? I use a $20 loop antenna I have rigged up myself, it lives in my attic: http://phk.freebsd.dk/loran-c/Ant

Re: [time-nuts] Loran C returning to a station near you...

tensive to run constantly. -- 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] Loran C returning to a station near you...

In message <73568e39-9467-4192-aeb8-c9c14a2bb...@n1k.org>, Bob Camp writes: >I notice in the papers that “infinite budget” does not seem to >apply to the US DOD these days. *cough* F-35 *cough* B61-mod12 *cough* -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...

Re: [time-nuts] Loran C returning to a station near you...

VLF range. The reason Loran-C "spreads crud" is *only* the combinationa of the pulse-groups and the periodicity of the GRI. The pulses themselves are entirely contained inside the allocated frequency band. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] Loran C returning to a station near you...

RM CPU on a sub $100 development board, I as a time-nut find that an incredibly silly argument... -- 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 adeq

Re: [time-nuts] Loran C returning to a station near you...

here is a + - + - sequence from all transmitters around the start of the period. But then again, I have spent far more of my life on Loran-C than can ever be justified :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeB

Re: [time-nuts] Loran C returning to a station near you...

goal is a reliable backup for GPS, there are smarter ways to use the 100kHz band than Loran-C pulses, and there really isn't much reason to stay compatible with Loran-C receivers. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD comm

Re: [time-nuts] LORAN-C reception in the UK

the system >name, often just referred to as Fredriksson. >http://www.antus.org/RT02.html Interesting, never heard of that before... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD sinc

Re: [time-nuts] Any other useful purpose for Austron 2100F or SRS FS700 receivers in US

to replace the Austron 5000 PDP/11 controlled monitoring receivers at the LORSTAs. -- 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] LORAN-C reception in the UK

concluded that 40% of *all* benefits came from Loran-C, at a yearly cost only a fraction of a single Galileo launch vehicle. -- 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] Loran and SRS FS700 in the UK

matically in that case. -- 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] Loran and SRS FS700 in the UK

t rather "has a better OCXO" -- 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] LORAN-C reception in the UK

for LORAN-C in the UK? I belive signals are currently assured until 2019. -- 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] Reeeely long term HP 5065A drift rate (13 year!)

13 years, but I suspect one does not ship a 5065A if it is continously locked :-) -- 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] HPGL and SVG (was Re: lawnmower robots may be the end of VLF timekeeping)

hk/pylt Which reads the display memory over HPIB and spits out SVG from it. The TDS504 I "cheated" and dumped EPS over HPIB and used a random web-service to convert to SVG. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD com

Re: [time-nuts] lawnmower robots may be the end of VLF timekeeping

s, and spent an afternoon writing code to screen-dump the HP8568 into SVG format for the very same reason. -- 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

[time-nuts] lawnmower robots may be the end of VLF timekeeping

I spent some time capturing some data today. The measurements is from my $20 loop-antenna in the attic, which is something like 8 meters up and 10 meters besides the lawn-mower loop: http://phk.freebsd.dk/time/20150509.html -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p

Re: [time-nuts] Important parameters for a GPS/GNSS antenna

ng to see if anechoic chamber >data really gave correct answers in free space. So this could be a realistic way for us to calibrate the phase-center of an antenna ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] Important parameters for a GPS/GNSS antenna

so that the stress is converted from torsion to longitudal tension and you'de don. Doing continous rotation may not even be a good idea, rotating 90 degrees every hour is probably a better idea from a processing point of view, as that wouldn't need special software. -- Poul-Henning

Re: [time-nuts] Tour of METAS (Swiss Federal Institute of Metrology) time lab: any questions or requests?

In message <554b6547.5070...@burnicki.net>, Martin Burnicki writes: >Poul-Henning Kamp wrote: >> Ask them how/why the HBG transmitter screwed up the 2006 leapsecond ? > >If I remember correctly then the transmitter would have needed to be >overhauled, which would

Re: [time-nuts] Tour of METAS (Swiss Federal Institute of Metrology) time lab: any questions or requests?

In message <7fa86d93-1c83-4fe8-84a0-ddb7a542a...@n1k.org>, Bob Camp writes: Ask them how/why the HBG transmitter screwed up the 2006 leapsecond ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD

Re: [time-nuts] Important parameters for a GPS/GNSS antenna

In message , "Tom Van Baak" writes: >When you post-process raw GPS data you get to include antenna phase >center / gain / az/el corrections for free. Speaking of which... I wonder if anybody ever made a rotating GPS antenna to average out the X-Y phase-center offset ?

Re: [time-nuts] [volt-nuts] The Art of Electronics

In message <20150417074427.ga31...@sol.ermione.com>, Andrea Baldoni writes: >Hello. >In the case someone missed the new, after years of waiting, the third edition >of the book in the subject is out! I received it last week, and yes, it's absolutely worth the money

Re: [time-nuts] 53230A noise floor

to alert Anders that what he has measured is not what he think he has measured. -- 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 expla

Re: [time-nuts] 53230A noise floor

EV of the measurement versus time and you will discover that the noise floor is not even close to being even. If you find a particular good spot and want to use it for measurements, the way to go is to tune the length of the cable for EXT REF (or use a tweakable delay line) -- Poul-Henning Ka

Re: [time-nuts] Obscure HP T/F instruments in ebay.fr

and I suspect we will see more and more former HP employees start to take an interest. We see this effect very clearly at the danish computer history museum where I'm active (datamuseum.dk) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC

Re: [time-nuts] Obscure HP T/F instruments in ebay.fr

t;Can anyone confirm? No idea, but that would be a plausible explanation. -- 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 adeq

Re: [time-nuts] Obscure HP T/F instruments in ebay.fr

r than 50% hit rate getting S&H reduced. -- 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

[time-nuts] Obscure HP T/F instruments in ebay.fr

Reference 311307936107 HP 5275 Time Interval Counter There may be more... -- 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] new tdc from Texas

sulting 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 explained by incompetence. ___ time-nu

Re: [time-nuts] MSF Scheduled Maintenance Periods

r setup? The most likely explanation is a switch-mode power-supply in the local environment. 60kHz is a very popular choice of switching frequency. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-taho

Re: [time-nuts] D term (was no subject)

In message <20150206153214.4d5f42edbdda4639fee1a...@kinali.ch>, Attila Kinali w rites: >On Mon, 26 Jan 2015 20:15:12 +0000 >"Poul-Henning Kamp" wrote: > >> The basic math of PID has been around for about 100 years. The invention >> of the servo (an

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