Re: [time-nuts] Modern motherboard with RS232 port

rt from some weirdness related to the videomemory not supporting 32bit writes in character mode, it works ok for me. -- 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] web presentation of data

62_b.svg It doesn't get any easier than that... -- 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] What size graphs do people like? (How big is yourscreen?)

andwidth to download before the person can see if it is of interest to >them. That is _exactly_ why you should use a vectorformat like SVG: Raster format is a waste of bytes for line graphics. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RF

Re: [time-nuts] What size graphs do people like? (How big is yourscreen?)

In message <68331.1344242...@critter.freebsd.dk>, "Poul-Henning Kamp" writes: >In message <501f80cc.2090...@rubidium.dyndns.org>, Magnus Danielson writes: >>On 08/06/2012 09:10 AM, David J Taylor wrote: >>> The absolute best thing would be to make the gra

Re: [time-nuts] What size graphs do people like? (How big is yourscreen?)

al for web-publishing, you might provide a PDF too, but >SVG is better if you want vectorized. I can highly recommend SVG, I use it in Pylt, examples: http://phk.freebsd.dk/misc/hp85662_a.svg http://phk.freebsd.dk/misc/hp85662_b.svg Try pressing '+' and '-' in your browser.

Re: [time-nuts] Leap second? Yay or nay?

y >moving it to the new alignment relative to solar day. Why bother ? Just make everybody use TAI and make T-O-D alignment a cultural thing rather than a numerological superstition ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBS

Re: [time-nuts] Leap second? Yay or nay?

In message <6A49BBA9110943DEA397D3F7929F32E3@garadm>, "Jean-Louis Noel" writes: >Hi, > >From: "Poul-Henning Kamp" > >> Testing software for correct handling of leap-seconds is a major undertaking >> which very few people have the kit and skill to

Re: [time-nuts] Leap second? Yay or nay?

asier to get the rest of the world to accept rule/standards-making based on TAI than GPS for political reasons. -- 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 ca

Re: [time-nuts] Leap second? Yay or nay?

very few people have the kit and skill to do. You can get better quality either by paying a lot more money for software or by removing or reducing the impact of this "gottcha" feature from the programs environment. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebs

Re: [time-nuts] Leap second? Yay or nay?

"What can you do with an extra second ?" as filler material on page 7 Whereas coverage of DST changes is "REMEMBER TO SET YOUR CLOCKS!" on the frontpage. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] So, how did you spend your leapsecond?

I spent it taking screengrabs of Twitter: http://phk.freebsd.dk/hacks/leap_20120630/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

Re: [time-nuts] TimePod 5330A announcement/info (was TimePod, cross-correlation fun and measurements)

In message <00bf01cd4d12$f83a41d0$e8aec570$@pop.net>, "John Miles" writes: Hi John, Congratulations on a good design. Why the 78 MHz sample frequency ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] zero crossing of venus

ime it took Venus to pass the Suns limb, and the time it took the center of Venus to pass across the Sun. No math given. -- 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] Paywall rant

with a crowbar. -- 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-nut

Re: [time-nuts] DDS in GPSDO design?

h would do a pretty good job, as would pretty much any streaming crypto chip in feedback mode. It's probably not cheaper than the FPGA, but you would avoid the VHDL issue. I like Rich's mixing synthesizer much better. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebs

Re: [time-nuts] DDS in GPSDO design?

In message <4fc2a5e9.7050...@partiallystapled.com>, Michael Tharp writes: >Does anyone have any comments or experience with DDS-based frequency >references? I belive that is basically how the optional "output generator" works for hydrogen masers. -- Poul-Henning Kamp

Re: [time-nuts] Serial port server .. any interest in a write up on using ?

ed ports. -- 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

Re: [time-nuts] Clocks for Audio gear

x27;re probably talking about one of those tripple-blind experiments ? (http://www.cco.caltech.edu/~boyk/sdttest.htm) -- 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] Can M12+T be improved?

e commands to do so. Those commands may have leaked subsequently, and the M12 may be different from the UT in this respect, but I doubt it is enough to just preplace the TCXO. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] M12+T sawtooth correction and additional filtering

ot; in the >Hn message. It's the mean of these values that determines the >virtual 1PPS (= the physical 1PPS + sawtooth correction). See also: http://phk.freebsd.dk/raga/sneak/ -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RF

Re: [time-nuts] Why 9,192,631,770 ??

. If they had used a more up to date astronomical result, we would have had a lower rate of leap seconds, essentially getting rid of the "one leap second every 18 months" average value. In the long term it doesn't make a difference of course, there earths slowing down will dominate.

Re: [time-nuts] Oh dear

less they have to (think "when can we actually see this star with this telescope" 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 ad

Re: [time-nuts] Oh dear

ration worth of european classical recordings: "good" being equal to "Karajan can hear it through his increasingly severe deafness" :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD sin

Re: [time-nuts] Oh dear

In message <1336415866.16321.14.camel@laptop>, Dan Mills writes: >On Mon, 2012-05-07 at 18:15 +0000, Poul-Henning Kamp wrote: >16 bits is actually fine as a distribution format, Yes, I agree with that, and lets use that agreement to stop the topic :-) -- Poul-Henning Kamp

Re: [time-nuts] Oh dear

digital: High distortion in weak passages. It is also why the CD media has changed rythmic music, which went from a love of distortion to a love of pure tones when the CD media made it possible to play loud pure tones. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd

Re: [time-nuts] Oh dear

t perfect clock so that the rate stays >the same but time interval between successive pulses varies randomly >between P(1-x) and P(1+x). > >How big would x have to be before anyone could detect any difference in >the sound? You have to tell us the sampling frequency before we can ans

Re: [time-nuts] Oh dear

he first generation of Philips CD players, CD-100 etc, which had "jitter" come up from the poor mechanics, because there were insufficient buffering before the de-interleaver. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBS

Re: [time-nuts] Oh dear

sure you read the description to discover what it's being sold for. The name of the company is even funnier: "Sonic Circus" :-) -- 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] DPLL for 10MHz

term >stability with a high stability OCXO and dont want to "cut into" >my fury and replace the OCXO. The Vectron TRU-50 is pretty good for that. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] Oh dear

to understand, >short, descriptions of "why using a Rb for your CD player is BS". You seem to be working under the assumption that they care about the measurable reality. They do not. This is about bling and about being better than the brother-in-law at something, it has nothing to d

Re: [time-nuts] Oh dear

ing annoying distractions. Unless, of course, you burn pure diamonds... -- 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] Oh dear

let, but I see that somebody has cornered that market now. Next step will be to try to sell them electricity produced on turbogenerators aligned to the earths magnetic field in order to deliver minimal low unharmonic distotion... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebs

Re: [time-nuts] Interesting paper: Don't GPSD' your Rb...

ro of shorter timespans. My experiment was inconclusive, but the idea is not unsound. -- 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 attribu

Re: [time-nuts] FS700 antenna

In message <4fa5cd62.3000...@rubidium.dyndns.org>, Magnus Danielson writes: >On 05/06/2012 02:11 AM, Poul-Henning Kamp wrote: >>> it's the GRI 90070 Edje chain, but the FS700 won't find the stations. >> >> Try 74990M also > >Tried it, no luck.

Re: [time-nuts] FS700 antenna

ins so I guess "Western Russia" at GRI 8 is >the one to look for. GRI 8 is very sensitive to any kind of CW on integral kHz frequencies so you'll probably get pretty bad SNR. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since

Re: [time-nuts] Interesting paper: Don't GPSD' your Rb...

ridges. If you cannot apply the negative sawtooth, you will get better results by disciplining almost any random quartz xtal, ovenized or not to the GPS, divide it down to PPS and then discipline the PRS10 to that. I belive that is the same thing the paper advocates, although they communicate it v

Re: [time-nuts] FS700 antenna

the place and your notch filter will only catch it every so often. The only thing that works for this, is to move your antenna away from the (primarily magnetic) fields of switch mode power supplies. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since

Re: [time-nuts] FS700 antenna

t you have a switch-mode power-supply in your house which wanders over the 80-120 kHz frequency band in a very noisy 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

[time-nuts] Interesting paper: Don't GPSD' your Rb...

This is pretty think, but interesting: http://tf.nist.gov/sim/Papers/Trigo_CPEM_2010.pdf -- 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] LORAN-C

BNC at the backside. -- 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

In message <1158.12.6.201.135.1335885236.squir...@popaccts.quikus.com>, "J. For ster" writes: >> Next step is to lock up the signal on an oscope, triggered by an >> accurate 11.148272 KHz signal ( reciprocal of 89700microsec). A HP5359A is great trigger-source for

Re: [time-nuts] An interesting freq counter

In message , Mark Sims writes: >With a rather freaky display that I have never seen: >http://www.electricstuff.co.uk/venner.html > Looks like IEE "One Plane Readout", wonderful technology. I have four such digits as a bedside clock. --

[time-nuts] FS700 is Z80 based ?

I guess I must have confused the FS700 with MegaPulses receiver, I always thought the FS700 was DSP based, but now that I read the manual I see that it is based on a Z80... Anyone have a copy of the EPROM ? -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP

Re: [time-nuts] PRS-10 input and output calibrations

cillators have the same default parameters being setup. You would clearly want to torque the timeconstant of the second PRS10 in that scenario, but idea is not without merit. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] PRS-10 input and output calibrations

e are threel obvious issues: Which flank you trigger on and which polarity and width the output pulse has. The output pulse from the PRS10 is pretty narrow, making it very easy to mistakenly use the wrong flank. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/

Re: [time-nuts] PRS-10 input and output calibrations

rate your 10-epsilon MHz for the PPSdiv. This general "vernier" method can be used to measure all sorts of tricky stuff, from interrupt latencies in operating system kernels to stuff like the above. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | T

Re: [time-nuts] Chinese Scopes

In message <4f8c3ecd.1080...@neon-john.com>, NeonJohn writes: >There is a rumor that one also needs an analog scope. Where analog scopes generally win is in X-Y mode, most digitals I've seen suck at that. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] Holy cesium clock, Batman!

In message <4f8326dc.4090...@jxh.com>, Jim Hickstein writes: >(They got Otto Preminger? I suppose even he had to work, back then.) I think you have the wrong idea here. It was a quite attractive thing to play a villain on batman. Not quite being on Dr. Who, but close. -- Poul-Hen

Re: [time-nuts] Holy cesium clock, Batman!

In message <4f81e48e.7040...@yahoo.com>, "Randy D. Hunt" writes: >Does Batman use a Cesium clock to determine Bat Time? Of course not! He uses the Bat-Clock! (Can't remember which exact episode, but it's quite close to the "Quick, hand be the bat-anti-shark-

Re: [time-nuts] 5370B Manual - Searchable?

In message <4228A5D7373F4DE7BD482AFEACF85458@narvik>, "David J Taylor" writes: >> This is the kind of important and detailed information I really >> wish we would collect in a wiki somewhere... >> >> -- >> Poul-Henning Kamp | UNIX since Zilo

Re: [time-nuts] 5370B Manual - Searchable?

and from >one edition of the manual to the next (while still being consistently wrong >in my experience). This is the kind of important and detailed information I really wish we would collect in a wiki somewhere... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org

Re: [time-nuts] 5370B Manual - Searchable?

In message <4f7fe2d1.4070...@verizon.net>, Rix Seacord writes: >Is that a function of the pdf file or the reader? It can be both. PDFs can have searchable indexes. Readers can have OCR facilities, most don't. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p.

Re: [time-nuts] Best reason

cks? SONET at the bottom and eBay endings at the top and a lot of stuff in the middle. -- 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 adequ

Re: [time-nuts] Best reason

In message , Jim Palfreyman writes: >So when a member of the general public says: > >Why do we need really accurate clocks? > >What is your answer? "Because accurate clocks is the central technology that makes GPS, mobile phones and the internet work." -- Poul-Hennin

Re: [time-nuts] Antenna Position

lic or to thick ceramics. -- 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 phase plots

phase change!) are what you correlate, the more, the better S/N you get. -- 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 explain

Re: [time-nuts] WWVB phase plots

robably measure >phase alignment pretty accurately with that. As usual it depends on your averaging period and thus stability of your timebase, but 20 microseconds isn't too hard 1200 km from the transmitter. If you want to measure propagation effects really precisely, DCF77 is your signa

Re: [time-nuts] WWVB BPSK Receiver Project? (fwd)

y implementation here: http://phk.freebsd.dk/misc/ChrisTraskAntenna.jpg I feed it 15 volts on the twinax pair, pull that out of the toroids centertap, regulated it with a 12V 3-terminal. You can see the prototype in the top right corner. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@

Re: [time-nuts] WWVB BPSK Receiver Project?

go and that is cheap. -- 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 BPSK Receiver Project? (fwd)

th ends, is centertapped and that's how I provide power to the antenna. I have successfully received the Russian "Omega-like" system at 9-15 kHz and I have detected but not demodulated the 86Hz submarine transmission. That's DC enough for me :-) -- Poul-Henning Kamp

Re: [time-nuts] WWVB BPSK Receiver Project? (fwd)

AC-coupled ;-) Not in my implementation, I have eliminated the input capacitor because the active element is 3cm from the PCB, and I drive the output with a centertapped transformer. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD commi

Re: [time-nuts] WWVB BPSK Receiver Project? (fwd)

plementation, it covered DC to 200MHz until I low-pass'ed 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 to malice what can adequat

Re: [time-nuts] WWVB BPSK Receiver Project? (fwd)

y flat filter (both freq+phase) in order to reliably recognize the proper zero-crossing to track. The more you disturb a Loran-C pulse, the more it just looks like a bit of a sine-function, and the harder it is to lock on the right zero-crossing. -- Poul-Henning Kamp | UNIX since Zilog Ze

Re: [time-nuts] WWVB BPSK Receiver Project? (fwd)

rom the >filter. But then again, time nuts are time nuts ;) Again: it most certainly can not be ignored for Loran-C -- 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

Re: [time-nuts] WWVB BPSK Receiver Project? (fwd)

o take an external clock signal. >The useful bandwidth of LF to HF radio is about 9kHz, You need more than 25kHz for good Loran-C -- 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] WWVB BPSK Receiver Project? (fwd)

oint about having 8 buffers per day is that you only compare 03:00-05:59 to 03:00-05:59 the previous or the next day, so the sun-effects almost entirely cancel out. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer |

Re: [time-nuts] WWVB BPSK Receiver Project? (fwd)

got me a new offset estimate every three hours and that did a pretty good job on both OCXO and Rb disciplining. -- 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] WWVB BPSK Receiver Project? (fwd)

And that math isn't >high school level anymore. This one isn't half bad: http://www.dspguide.com/ -- 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] WWVB BPSK Receiver Project? (fwd)

termination, and for that lead/center/lag is the way to go, but you may still want to average for a minute, then resolve the phase using the phase-modulation, rather than run it in real-time. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 Fre

Re: [time-nuts] WWVB BPSK Receiver Project? (fwd)

uch anything else. -- 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 BPSK Receiver Project?

In message , Chris Albertson writes: >But you are right in that using dttsp [...] GNU Radio If the objective here is time-nuttery, both of these are badly suited because they are built to extract the rapidly changing information, not for long averages of carrier phase. -- Poul-Henning K

Re: [time-nuts] WWVB BPSK Receiver 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 attribute to malice what can adequately be explained by incompetence. ___ time-nuts mailing lis

Re: [time-nuts] WWVB BPSK Receiver Project?

F77 on half kHz grid, you need a 2 msec = 2000 samples long buffer. -- 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] WWVB BPSK Receiver Project? (fwd)

uld mean you need a pretty recent chip as HighSpeed USB has not >been introduced into the uC world for more than 2 years or so. USB2, not USB3. -- 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] WWVB BPSK Receiver Project? (fwd)

ver. The ARM chip is plenty powerful to do pretty much anything you are to on its own once you give it the code to do so. -- 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] WWVB BPSK Receiver Project?

ance: http://phk.freebsd.dk/loran-c/CW/ -- 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 BPSK Receiver Project?

what being a time-nut is all about ? VLF signals, once they have phase-code, are pretty good for frequency stabilization, you just need to use an averaging time of 24 hours. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD co

Re: [time-nuts] WWVB BPSK Receiver Project?

ime domain. Here's a really interesting platform for VLF SDR work: http://www.seeedstudio.com/depot/dso-nano-v2-p-681.html?cPath=174 1MSPS 12 bit ADC, input amplifier/attenuator, display, USB interface, and rechargeable lithium battery. For $89... Too bad it doesn't have a 10

Re: [time-nuts] WWVB BPSK Receiver Project?

emed interested, so I've just used my hacked up rig. -- 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 e

Re: [time-nuts] Three HP oldies

eadable. Try Graphics Interchange Format gif >to preserve computer generated details like lines >and text. PNG is also a good choice, both for pictures and for graphics. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] Loran in the US

tering to some recently discovered VIP Loran-C users. I'd be very surprised if LightSquared nuking GPS reliability doesn't have something to do with this. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | B

Re: [time-nuts] Loran in the US

have gone on and on about that topic). Well, they do actually regulate telecoms, so they may simply be told that it will be a condition for their licenses. That happened with respect to power backups for cellular towers after Katrina showed the inadequacy of 3 hours lead-acid backup. -- Poul-

Re: [time-nuts] MicroLogic ML200 Loran-C

In message <2561.12.6.201.116.1331169308.squir...@popaccts.quikus.com>, "J. For ster" writes: >Last seen, the 4004 chips were much in demand (perhaps by gamers) And "chip-collectors" But they're not leaving that receiver as long as there is smoke in them.

Re: [time-nuts] Loran in the US

Has anybody asked them how good time&freq they're trying to deliver ? I would assume that they are aiming for a backup for GPS in telecom-GPSDO context. If so, frequency stability is priority number one and time is probably just "better than 100msec" or so -- Poul-Hennin

Re: [time-nuts] MicroLogic ML200 Loran-C

. -- 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 l

[time-nuts] MicroLogic ML200 Loran-C

that it is based on an Intel 4004 microcomputer and after resocketing some ICs it seems to work better. If anybody has any information/manuals etc. for this beast, I'd love to get hold of a copy. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP sinc

Re: [time-nuts] Loran in the US

good GPS, I don't see much of a problem. -- 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 in the US

t's absolutely out of the question, as you well know all our problems these days are there isn't enough God in the constitution or something. Thats why some people in the military is looking into a modern more lightweight version of "Tactical Loran" for use when GPS is jammed. -- Po

Re: [time-nuts] Loran in the US

> >Would this mean depending on private parties for precision timing and >positioning [using that particular system, of course]? Well, that could be your own choice, you can tell your receiver which transmitters you trust. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@f

Re: [time-nuts] Loran in the US

pectrum technology, with a data-channel so receivers don't have to have a hard coded list of all transmitters. That would make roll-out a matter not for governments, but for airports, harbours and other interested parties, like for instance DME. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3

Re: [time-nuts] Loran in the US

and give vastly better results than LORAN-C. It's mentioned somewhere in the ILA's archives, probably early '80ies. The idea has been partially validated by DCF77's phase-coding. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since R

Re: [time-nuts] Austron 2000C Loran C Receiver

see the Russian Chayka chains here. Yeah, I usually hear the Chayka too here in Denmark. Unfortunately the 8000 GRI of the eastern Chayka is extremely bad for S/N as pretty much any and all integral kHz CW stations do not average out like the do for 2, 3 or 4 digit GRis. -- Poul-Henning Kamp

Re: [time-nuts] Questions about Austron 5000 Loran C receiver

e out how to put another computer on the 5000, but it would be a lot of work, no doubt about that. -- 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] Questions about Austron 5000 Loran C receiver

>name scheme both receivers are 2100F and look the same. Hmm, interesting. Youre r.G and r.107 look a lot like each other, and nothing much like my r.107 -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since

Re: [time-nuts] Questions about Austron 5000 Loran C receiver

uldn't mind reading out the EPROMS of their 2100's, I would appreciate it. My aim is to disassemble them and find out more about how these receivers actually work. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] Questions about Austron 5000 Loran C receiver

d a random transformer to attach your antenna. Here is a time-lapse gif with a nights worth of loran-C: http://phk.freebsd.dk/AducLoran/animation.gif Have fun... -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer

Re: [time-nuts] Questions about Austron 5000 Loran C receiver

ter that it was >generally paired with? If so, how is it done? Only by substituting a different computer, running a program which controls the receiver like the PDP-8 would have done. This may be easier than it sounds, provided you know what the heck the PDP/8 did. Otherwise: forget all about it.

Re: [time-nuts] Loran transmitters back on the air.

ance at sea, high in the air and at ground. The latter sucks most, which is why you need detailed maps of local corrections. I wonder how much of a role the recent "you could loose GPS to stupid politics" experience has in this. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20

Re: [time-nuts] Neutrinos not so fast? (defectove connector)

nal. It can add a signal where one was missing before, but it does not change the timing of a signal that already made it through by a consistent 60 nanoseconds. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | B

Re: [time-nuts] Neutrinos not so fast? (defectove connector)

e. You really don't want to defend your phd dissertation, being known as the idiot who made a fool of both CERN and SanGrasso in one go. -- 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

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