Re: [time-nuts] New unit of time measurement
I like the ped-countdown displays here (San Jose, US) because I can better judge if I'll need to stop or not when approaching an intersection. I've noticed the drivers getting worse and worse about following basic laws like stopping at red lights. Rush hour only makes things worse- at the freeway on ramp intersection near where I work, an average of 5 cars go through the intersection after the light turns green for the other direction. To be fair, I've done the same when I am carrying something delicate and mis-judged the light, but these people just want to get home faster- I've often wished we could shoot offending cars with indelible paint balls... and the CHP could write tickets when you had enough hits on your car... Worst offenders? BMW and Audi drivers... I can dream... -Dave - Original Message - From: Poul-Henning Kamp p...@phk.freebsd.dk To: Discussion of precise time and frequency measurement time-nuts@febo.com Sent: Sunday, January 15, 2012 10:31:45 PM Subject: Re: [time-nuts] New unit of time measurement In message 2867F1FA0E254465AF8CA85C85ED0C79@narvik, David J Taylor writes: In China I've seen down-counting LED displays for the red sign. But this is just to simple for Europe. Badly. I've certainly seen countdown display for pedestrians in several European cities. They are not used for cars here in Denmark because a certain testosterone driven segment of drivers think they are in pole-position when they see a count-down. -- 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 -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Odd pulses on 1PPS output- 5680A
Finally got a chance to play with my 5680A, and was happy to see that it locks in about 45 seconds from cold. The messy 10Mhz output is about 80mVpp, but the weird thing is the output on pin 6 (1PPS). The output is a 20 microsecond, 1.8Vpp, square wave that is clean on top, but rings like crazy on the bottom. When zoomed in on, the 10Mhz signal can be seen as noise on this output. My PS output is clean and the 5v is being provided by an inline 7805 (with caps). The onboard switcher section is not populated, so I'm at a loss as to where the signal is coming from. -Dave ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Controlling FEI 5680A
On Sun, 15 Jan 2012 16:45:56 +0100 Magnus Danielson mag...@rubidium.dyndns.org wrote: A short notice on embedded CPU/MPUs into FPGAs. Using PIC or AVR might be tempting, but I consider any clone dirty from a rights perspective, MIPS for instance have been very protective on their side, so has ARM. So far has the SPARC been the only big one being accepted in their LEON-x variants that I know of. We be sad to see the cotton industry level being smashed by the big firm lawyers. Erm... You trust too much in corporate mambojambo... 1) These clones implement an ISA (instruction set architecture) 2) You cannot copyright an ISA (the same as you cannot copyright a header file) 3) You can only copyright a specific implementation 4) You can patent certain ways how instructions work (see MIPS) These clones are thus not any more dirty then their originals. Only that the companies don't want you to use them. Which, from their point of view is understandable: It takes time and money to come up with a good ISA. It is something that you cannot easily protect (see above). But the companies want you to buy _their_ chips, not the ones from their competitor. Hence, if they cannot get rid of those clones, they try to get as much FUD out as possible to ensure that nobody is using those clones. If this clone is produced by a company, the company will challange that FUD and get rid of it legally. If the clone is done by a few guys in their free time and released as open source (resp open hardware), then they will not have the time and money to battle that FUD. and innocent people like you will fall for it. Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Controlling FEI 5680A
On Sun, 15 Jan 2012 11:27:27 -0500 paul swed paulsw...@gmail.com wrote: FPGAs are generally intended for the mass market with a steep learning curve. Though they can be pressed into whats of interest to time-nuts it simply seems like a overly complicated technology and method for a non-mass market solution. Actually, they are not. In the mass market, you dont want to use FPGAs due to their high cost. As soon as you produce more then 10k pieces (in total) you start thinking about doing an ASIC. And the learning curve isn't any more steep than for learning how to work with a uC. It's just that most people know already a bit of programming which makes it far easier to learn enough C to do something with a uC. At the same time, programming experience makes it more difficult to learn VHDL/Verilog, because people think it works like a programming language which it definitly does not. But yes, you are right. An FPGA is probably not the right thing. Not because it is more difficult, but rather because there are less tools and less documentation available. Hence making it more difficult for the hobbyist to handle FPGAs than uCs. Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] NTP on steroid (was: a hijacked thread)
On Sun, 15 Jan 2012 19:24:24 -0800 gary li...@lazygranch.com wrote: Is it possible these wireless providers are using something like NTP on steroids with a Rb clock rather than GPSDO? Nope. NTP does not give you enough stability, nor accuracy, nor precision. The best you can get out of NTP is about 1ms. While UMTS needs something in the us range for proper working IIRC. Attila Kinali -- The trouble with you, Shev, is you don't say anything until you've saved up a whole truckload of damned heavy brick arguments and then you dump them all out and never look at the bleeding body mangled beneath the heap -- Tirin, The Dispossessed, U. Le Guin ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Austron 2010B Operations Manual
Hello group, I hope the new year finds you all well? I have just received an Austron 2010B Disciplined frequency standard. Could some kind soul help me out with an operations manual? Many thanks, Mark inline: image001.gif___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] NTP on steroid (was: a hijacked thread)
The best you can get out of NTP is about 1ms. While UMTS needs something in the us range for proper working IIRC. Attila Kinali NTP fed with a PPS source can do much better than 1 ms. Here's a non-temperature-controlled, simple Intel Atom system providing within 10 microseconds using FreeBSD 8.0: http://www.satsignal.eu/mrtg/pixie_ntp.html Of course, if you mean over the Internet, then even 1 ms might be optimistic! Cheers, David -- SatSignal software - quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] ATT WP 92066-L5 (RB)
On 1/15/2012 10:24 PM, gary wrote: Is it possible these wireless providers are using something like NTP on steroids with a Rb clock rather than GPSDO? They are moving to using IEEE 1588 for site synchronization. I guess you could consider it something like NTP on steroids. It requires hardware assist to achieve the accuracy needed. No need for an Rb for holdover. Timing is carried with the same packets which carry the voice traffic. If the packets aren't getting through, then you're dead anyway. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] New unit of time measurement
Hehe - try driving in Napoli some day - makes Roma seem positively sane, and Torino is civilised compared to Roma! D. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] New unit of time measurement
This is why the North-Italy territory wants to be separeted the rest of Italy..hihi EP. -Original Message- From: David C. Partridge david.partri...@perdrix.co.uk To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Sent: Mon, Jan 16, 2012 12:59 pm Subject: Re: [time-nuts] New unit of time measurement Hehe - try driving in Napoli some day - makes Roma seem positively sane, and orino is civilised compared to Roma! D. __ ime-nuts mailing list -- time-nuts@febo.com o unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts nd follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] NTP on steroid (was: a hijacked thread)
The best you can get out of NTP is about 1ms. While UMTS needs something in the us range for proper working IIRC. Attila Kinali NTP fed with a PPS source can do much better than 1 ms. Here's a non-temperature-controlled, simple Intel Atom system providing within 10 microseconds using FreeBSD 8.0: http://www.satsignal.eu/mrtg/pixie_ntp.html Of course, if you mean over the Internet, then even 1 ms might be optimistic! Cheers, David NTP on steroids taken literally could point at PTP (IEEE-1588) http://en.wikipedia.org/wiki/Precision_Time_Protocol I have heard talks of accuracies down towards 20ns. There is also something called hardware NTP, which would give sub 1us accuracies. -- Björn ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] time-nuts Digest, Vol 90, Issue 115
Il 16/01/2012 13.00, time-nuts-requ...@febo.com ha scritto: Send time-nuts mailing list submissions to time-nuts@febo.com To subscribe or unsubscribe via the World Wide Web, visit https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts or, via email, send a message with subject or body 'help' to time-nuts-requ...@febo.com You can reach the person managing the list at time-nuts-ow...@febo.com When replying, please edit your Subject line so it is more specific than Re: Contents of time-nuts digest... Today's Topics: 1. Re: New unit of time measurement (David C. Partridge) -- Message: 1 Date: Mon, 16 Jan 2012 11:59:21 - From: David C. Partridgedavid.partri...@perdrix.co.uk To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Subject: Re: [time-nuts] New unit of time measurement Message-ID:00688D7882814DACA914E805BF6A4018@APOLLO Content-Type: text/plain; charset=US-ASCII Hehe - try driving in Napoli some day - makes Roma seem positively sane, and Torino is civilised compared to Roma! D. -- ___ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts End of time-nuts Digest, Vol 90, Issue 115 ** To: 'Discussion of precise time and frequeny measurement' Subject : Re: [time-nuts] New unit of time measurement Hello guys, here in central Italy( i live near Florence ) we have redefined one microsecond lenght: it is the time between green light goes on at semaphore and when the guy after you hit clacson... :-) David, never seen traffic in Catania, Sicily ? hehehe... Cheers, Piero. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] leap second end of June 2012
http://forums.qrz.com/showthread.php?329468-This-year-a-day-and-a-second-longer -- Doc Bill Dailey KXØO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] leap second end of June 2012
INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS) SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES SYSTEMES DE REFERENCE SERVICE DE LA ROTATION TERRESTRE OBSERVATOIRE DE PARIS 61, Av. de l'Observatoire 75014 PARIS (France) Tel. : 33 (0) 1 40 51 22 26 FAX : 33 (0) 1 40 51 22 91 e-mail: services.iers@obspm.frhttp://hpiers.obspm.fr/eop-pc Paris, 5 January 2012 Bulletin C 43 To authorities responsible for the measurement and distribution of time UTC TIME STEP on the 1st of July 2012 A positive leap second will be introduced at the end of June 2012. The sequence of dates of the UTC second markers will be: 2012 June 30, 23h 59m 59s 2012 June 30, 23h 59m 60s 2012 July 1, 0h 0m 0s The difference between UTC and the International Atomic Time TAI is: from 2009 January 1, 0h UTC, to 2012 July 1 0h UTC : UTC-TAI = - 34s from 2012 July 1,0h UTC, until further notice: UTC-TAI = - 35s Leap seconds can be introduced in UTC at the end of the months of December or June, depending on the evolution of UT1-TAI. Bulletin C is mailed every six months, either to announce a time step in UTC or to confirm that there will be no time step at the next possible date. Daniel GAMBIS Head Earth Orientation Center of IERS Observatoire de Paris, France http://data.iers.org/products/16/14889/orig/bulletinc-043.txt -- Doc Bill Dailey KXØO ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] New unit of time measurement
please, before write look in your home than respect other people. thanks Luciano -- Luciano P. S. Paramithiotti IZ5JHJ - Original Message From: Discussion of precise time and frequency measurement time-nuts@febo.com To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Subject: Re: [time-nuts] New unit of time measurement Date: Jan 16, 2012 01:01 PM Hehe - try driving in Napoli some day - makes Roma seem positively sane, and Torino is civilised compared to Roma! D. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. Sent to you using Uebimiau Webmail version 3.11 Developed by Dave and Todd at http://www.manvel.net and http://www.tdah.us ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Controlling FEI 5680A
Hi The lock range of the 5680 is limited only by the range of the VCXO. The DDS has way more range than the VCXO does and there's nothing else in that loop. The rubidium cell does not change frequency when the DDS is tuned, so that entire loop is not a limiting factor. As you approach the edge of lock things will get a bit funny, that's true of any PLL. Based on the VCXO pictures, it's not a very fancy part. After five or more years in the field, some of them are reported to not lock at 10 MHz. Tuning one off frequency will be a try it and see sort of thing. When they left the factory they probably tuned at least +/- 3 ppm around 10 MHz and possibly ten times that. The VCXO likely has a temperature drift in the 100 to 1000 ppb range. The loop must take care of that to operate at all. Temperature performance per the data sheet is in the 0.1 ppb range, aging 0.01 ppb / mo (also from the data sheet). We have at least one example with a lot better aging than the data sheet would suggest. The only real question is weather the minimum tune range is greater than the aging for a couple years plus the variation due to temperature and other enviromental effects. The total of all of them is likely under 1 ppb and certainly under 5 ppb. The VCXO certainly will tune that far. Put another way, the tuning to put it on frequency is much smaller than the temperature drift of the VCXO. The loop is working much harder to stabilize the VCXO than it is to handle the tuning word. Bob On Jan 15, 2012, at 5:11 PM, Chris Albertson wrote: We are talking about a controller for the new batch of $38 FE5680 units right? Unless you modify these the frequency must be controlled by RS232. Then you said FPGA right?If so why worry about the bits in the counter. You can change it later with a few minutes effort. If you have 250,000 gates that can run at 200MHz you don't have to ration them. Go for 24 bits and run the counter at 200MHz. The hard part is the FE5680, I don't think anyone here really understands it yet. How many DDS steps can you move it before it goes out of lock.Aging and temp co. are still TBD That is another change from a Sherra type controller, the FE5680 has a lock bit. You may as well use it to disable sending frequency change commands One other front end change. I few people have Thunderbolts and it would be faster to lock the FE5680 to the 10MHz signal then to the PPS. On Sun, Jan 15, 2012 at 2:11 AM, ewkeh...@aol.com wrote: I am staying out of that discussion due to lack of knowledge, My question is wether the input circuit is acceptable or if some one has a different solution. We have integrated the Shera input including the interrupt counter on the chip, so there are only three interface pins, interrupt, data out and clock from the PIC to transfer the data. The interrupt count is pin selectable, just like the 5/10 MHz divide. We are presently looking at increasing the counter from 16 to 20 or 24 bits. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Controlling FEI 5680A
On 1/16/12 2:44 AM, Attila Kinali wrote: On Sun, 15 Jan 2012 11:27:27 -0500 paul swedpaulsw...@gmail.com wrote: FPGAs are generally intended for the mass market with a steep learning curve. Though they can be pressed into whats of interest to time-nuts it simply seems like a overly complicated technology and method for a non-mass market solution. Actually, they are not. In the mass market, you dont want to use FPGAs due to their high cost. As soon as you produce more then 10k pieces (in total) you start thinking about doing an ASIC. And the learning curve isn't any more steep than for learning how to work with a uC. It's just that most people know already a bit of programming which makes it far easier to learn enough C to do something with a uC. At the same time, programming experience makes it more difficult to learn VHDL/Verilog, because people think it works like a programming language which it definitly does not. But yes, you are right. An FPGA is probably not the right thing. Not because it is more difficult, but rather because there are less tools and less documentation available. Hence making it more difficult for the hobbyist to handle FPGAs than uCs. Precisely so, particularly the tools. FPGAs (especially bigger ones, not just PALs and CPLDs) have been around about 20-25 years. I seem to remember going to some Xilinx seminars in the late 80s, when they were proud of their simulated annealing place and route running on a 286. So they've had only a few decades of development on the tool chain, compared to more traditional high level languages, where the basic computer architecture has been around 100 years, and compilers have been around for 60. There's also more genericness by now in the VonNeumann Model programming world: there must be 100 different CPU families out there, and we've converged to only a few basic programming models. THere's only a few FPGA architectures out there, and there's really only two different languages Verilog and VHDL. And as Attila points out, both of those look superficially like ordinary programming (particularly VHDL) and you can even write sequential programs in them, but the underlying hardware isn't even remotely like that, so you are seduced into a very non-optimal design style. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] New unit of time measurement
d.sei...@comcast.net schrieb: could write tickets when you had enough hits on your car... Worst offenders? BMW and Audi drivers... Here in Germany too. The worst drivers are the ones with license plates beginning with LB- AND driving Audi or BMW. LB means Ludwigsburg - a city near Stuttgart. Stuttgart - Porsches. Curiosly they drive seldom such fast as BMW and Audi on small streets here. Looks like BMW and Audi drivers need to rise money all the way whereas Porsche drivers have money already enough. An arabic saying: Only the poor man have to run his way. - Henry -- ehydra.dyndns.info ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] New unit of time measurement
On 1/16/12 6:47 AM, Timeok wrote: please, before write look in your home than respect other people. thanks Luciano Luciano's point is well taken. Every place has it's idiosyncratic driving things. Some are more different than others. I found Rome to be fairly well disciplined for a big city. I'd sooner step off the curb into the road reading a paper and not looking in Rome than New York, that's for sure. I think there is a general trend that warmer countries have wilder driving just because there's more opportunity for driving and more cars (because they last longer?). And to a certain extent, more driving leads to a familiarity with local customs, which may diverge from one's home area. I drive in Los Angeles, and it's nothing here to be in tightly packed 75 mi/hr (120 km/hr) platoons zooming about merging and splitting in 4 way interchanges, but we have relatively little of the 5 lanes squeezing down to 2 like you find in the US NorthEast (Boston, I'm looking at you). So people from back east find winding through the mountains at 65 mi/hr a bit trying, but have no problem in downtown LA. The other thing is signage. Everybody does their signs a bit differently (even in the US), so your plan-ahead navigation tends to get screwed up, even if the immediate vehicle management is ok. That tends to make driving in a foreign country a bit more exciting. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Simple Super Ripple Eater
There have been discussions in the past about ways to reduce regulator output noise or clean-up oscillator or voltage reference power supplies. Here's an article from Design Ideas in Electronic Design that looks promising. It has pretty decent rejection even at 1 Hz. http://electronicdesign.com/article/power/Simple-Super-Ripple-Eater-Also-Cleans-Battery-Based-Supply.aspx Note that the figures don't display properly (at least in Firefox) with anything but the embedded links in the text. - John ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Simple Super Ripple Eater
On Mon, Jan 16, 2012 at 12:17 PM, John Lofgren jlofg...@lsr.com wrote: There have been discussions in the past about ways to reduce regulator output noise or clean-up oscillator or voltage reference power supplies. Here's an article from Design Ideas in Electronic Design that looks promising. It has pretty decent rejection even at 1 Hz. http://electronicdesign.com/article/power/Simple-Super-Ripple-Eater-Also-Cleans-Battery-Based-Supply.aspx Am I wrong in assuming this is a similar to a circuit mentioned in time-nuts in the past in regards to voltage regulator noise, Finesse Voltage Regulator Noise! from Wenzel Associates? http://www.wenzel.com/documents/finesse.html ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Simple Super Ripple Eater
On Mon, 16 Jan 2012 12:48:24 -0500, michael taylor mct...@gmail.com wrote: On Mon, Jan 16, 2012 at 12:17 PM, John Lofgren jlofg...@lsr.com wrote: There have been discussions in the past about ways to reduce regulator output noise or clean-up oscillator or voltage reference power supplies. Here's an article from Design Ideas in Electronic Design that looks promising. It has pretty decent rejection even at 1 Hz. http://electronicdesign.com/article/power/Simple-Super-Ripple-Eater-Also-Cleans-Battery-Based-Supply.aspx Am I wrong in assuming this is a similar to a circuit mentioned in time-nuts in the past in regards to voltage regulator noise, Finesse Voltage Regulator Noise! from Wenzel Associates? http://www.wenzel.com/documents/finesse.html It is a series configuration instead of a shunt configuration. They both accomplish the same thing but in different ways. The Wenzel design requires gain matching but should be unconditionally stable. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Controlling FEI 5680A
On Mon, Jan 16, 2012 at 2:44 AM, Attila Kinali att...@kinali.ch wrote: But yes, you are right. An FPGA is probably not the right thing. Not because it is more difficult, but rather because there are less tools and less documentation available. Hence making it more difficult for the hobbyist to handle FPGAs than uCs. This is beginning to change. I think I'm going to try learning. The numbers are just to good, 250,000 logic gates that run at 100Mhz all on an easy to interface PCB with software for $50. And the best part is you can re-program it up after to build something. So you only need to buy one FPGA board. They get re-programmed on every power cycle. and (2) not waiting to order parts, you can try an idea right away. The Up is easier to use but always you end up with a bunch of other ICs in the design. the FPGA should let you do most of hat those ICs do and whatever the uP can do. For $50 I'll learn something, even if it is These things are not as useful as I thought. And I agre with you about the CPU cores. Just use them. My guess is that most FPGA applications have a uP core inside. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] NTP on steroid (was: a hijacked thread)
On Mon, Jan 16, 2012 at 2:51 AM, Attila Kinali att...@kinali.ch wrote: The best you can get out of NTP is about 1ms. While UMTS needs something in the us range for proper working IIRC. My NTP server runs at about 2 or 3 uSec level. It is nothing special. Just an $85 Atom board running Linux and a $15 Oncore GPS. With effort I could do twice as good. But if you are talking about Windows PCs using the network to sync to a server then , yes 1MS is very good. 10MS is typical Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Simple Super Ripple Eater
Here is a hand-corrected version: http://ehydra.dyndns.info/NG/time-nuts/Simple%20power%20supply%20ripple%20rejection%20for%20battery%20systems.zip - Henry John Lofgren schrieb: There have been discussions in the past about ways to reduce regulator output noise or clean-up oscillator or voltage reference power supplies. Here's an article from Design Ideas in Electronic Design that looks promising. It has pretty decent rejection even at 1 Hz. http://electronicdesign.com/article/power/Simple-Super-Ripple-Eater-Also-Cleans-Battery-Based-Supply.aspx Note that the figures don't display properly (at least in Firefox) with anything but the embedded links in the text. -- ehydra.dyndns.info ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] NTP on steroid (was: a hijacked thread)
When I said on steroids I meant a scheme similar to NTP, but something run by the wireless companies themselves, not run of the mill NTP. -Original Message- From: Chris Albertson albertson.ch...@gmail.com Sender: time-nuts-boun...@febo.com Date: Mon, 16 Jan 2012 10:54:34 To: Discussion of precise time and frequency measurementtime-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] NTP on steroid (was: a hijacked thread) On Mon, Jan 16, 2012 at 2:51 AM, Attila Kinali att...@kinali.ch wrote: The best you can get out of NTP is about 1ms. While UMTS needs something in the us range for proper working IIRC. My NTP server runs at about 2 or 3 uSec level. It is nothing special. Just an $85 Atom board running Linux and a $15 Oncore GPS. With effort I could do twice as good. But if you are talking about Windows PCs using the network to sync to a server then , yes 1MS is very good. 10MS is typical Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Controlling FEI 5680A
On 01/16/2012 11:31 AM, Attila Kinali wrote: On Sun, 15 Jan 2012 16:45:56 +0100 Magnus Danielsonmag...@rubidium.dyndns.org wrote: A short notice on embedded CPU/MPUs into FPGAs. Using PIC or AVR might be tempting, but I consider any clone dirty from a rights perspective, MIPS for instance have been very protective on their side, so has ARM. So far has the SPARC been the only big one being accepted in their LEON-x variants that I know of. We be sad to see the cotton industry level being smashed by the big firm lawyers. Erm... You trust too much in corporate mambojambo... 1) These clones implement an ISA (instruction set architecture) 2) You cannot copyright an ISA (the same as you cannot copyright a header file) 3) You can only copyright a specific implementation 4) You can patent certain ways how instructions work (see MIPS) These clones are thus not any more dirty then their originals. Only that the companies don't want you to use them. Which, from their point of view is understandable: It takes time and money to come up with a good ISA. It is something that you cannot easily protect (see above). But the companies want you to buy _their_ chips, not the ones from their competitor. Hence, if they cannot get rid of those clones, they try to get as much FUD out as possible to ensure that nobody is using those clones. If this clone is produced by a company, the company will challange that FUD and get rid of it legally. If the clone is done by a few guys in their free time and released as open source (resp open hardware), then they will not have the time and money to battle that FUD. and innocent people like you will fall for it. While I essentially agrees with you, I don't want to be on the wrong end of their lawyers. That's all I'm saying. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] 15 Seconds error...??
Hello, TimeNutters-- Can anyone shed some light on why there is a 15 sec difference between the large digit time display on my Lady Heather display and WWV...? I have been accused of living on another planet-- maybe it is true after all and that is why there is such a time difference...?? Thanks-- Mike Baker ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
Mike, That usually means you're running GPS time instead of UTC. Check also against http://leapsecond.com/java/gpsclock.htm /tvb Hello, TimeNutters-- Can anyone shed some light on why there is a 15 sec difference between the large digit time display on my Lady Heather display and WWV...? I have been accused of living on another planet-- maybe it is true after all and that is why there is such a time difference...?? Thanks-- Mike Baker ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
GPS time v. UTC ? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
GPS has its own time scale. Part of the GPS data stream contains the number of seconds that GPS and UTC differ by. -Brian, WA1ZMS -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Rae Sent: Monday, January 16, 2012 7:21 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] 15 Seconds error...?? GPS time v. UTC ? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
GPS was incepted in 1982, at which point it was equal to UTC ; since then, 15 leap seconds were introduced to UTC, thus the 15-second offset and by next July 1st, it will be 16 seconds. The most common use of GPS time (hybrid?) is the Android system time, even though Samsung Android phones use UTC discipline, possibly not thinking like Google that GPS time is so prevalent Christopher On Mon, Jan 16, 2012 at 19:25, Brian, WA1ZMS wa1...@att.net wrote: GPS has its own time scale. Part of the GPS data stream contains the number of seconds that GPS and UTC differ by. -Brian, WA1ZMS -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Rae Sent: Monday, January 16, 2012 7:21 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] 15 Seconds error...?? GPS time v. UTC ? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
Hi If it's a constant offset, UTC vs GPS. If it's variable - loading on your PC. I can pretty easily get LH to read 45 seconds off by trying to do to much at once on the machine. Bob On Jan 16, 2012, at 7:02 PM, Michael Baker mp...@clanbaker.org wrote: Hello, TimeNutters-- Can anyone shed some light on why there is a 15 sec difference between the large digit time display on my Lady Heather display and WWV...? I have been accused of living on another planet-- maybe it is true after all and that is why there is such a time difference...?? Thanks-- Mike Baker ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Controlling FEI 5680A
Hi Don't forget to toss RAM, Flash, EEPROM, brown out detection, and a clock oscillator on your board. You get all that stuff built in on a sub $5 / 100 Mhz micro, but not on a FPGA. I'm not saying you can't take care of all that on a board, just that you need to plan ahead. Bob On Jan 16, 2012, at 1:48 PM, Chris Albertson albertson.ch...@gmail.com wrote: On Mon, Jan 16, 2012 at 2:44 AM, Attila Kinali att...@kinali.ch wrote: But yes, you are right. An FPGA is probably not the right thing. Not because it is more difficult, but rather because there are less tools and less documentation available. Hence making it more difficult for the hobbyist to handle FPGAs than uCs. This is beginning to change. I think I'm going to try learning. The numbers are just to good, 250,000 logic gates that run at 100Mhz all on an easy to interface PCB with software for $50. And the best part is you can re-program it up after to build something. So you only need to buy one FPGA board. They get re-programmed on every power cycle. and (2) not waiting to order parts, you can try an idea right away. The Up is easier to use but always you end up with a bunch of other ICs in the design. the FPGA should let you do most of hat those ICs do and whatever the uP can do. For $50 I'll learn something, even if it is These things are not as useful as I thought. And I agre with you about the CPU cores. Just use them. My guess is that most FPGA applications have a uP core inside. Chris Albertson Redondo Beach, California ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
Correct me if I'm wrong, but UTC gets corrected from time to time, but many things depend on GPS time to be consistent (no jumps), so they can't adjust it. -Original Message- From: Brian, WA1ZMS wa1...@att.net Sender: time-nuts-boun...@febo.com Date: Mon, 16 Jan 2012 19:25:30 To: 'Discussion of precise time and frequency measurement'time-nuts@febo.com Reply-To: wa1...@att.net, Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] 15 Seconds error...?? GPS has its own time scale. Part of the GPS data stream contains the number of seconds that GPS and UTC differ by. -Brian, WA1ZMS -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Dan Rae Sent: Monday, January 16, 2012 7:21 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] 15 Seconds error...?? GPS time v. UTC ? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] New unit of time measurement
They are used in Russia, and that is pretty much what is happening. I can't imagine those being used in France... Didier KO4BB Sent from my BlackBerry Wireless thingy while I do other things... -Original Message- From: Poul-Henning Kamp p...@phk.freebsd.dk Sender: time-nuts-boun...@febo.com Date: Mon, 16 Jan 2012 06:31:45 To: Discussion of precise time and frequency measurementtime-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] New unit of time measurement In message 2867F1FA0E254465AF8CA85C85ED0C79@narvik, David J Taylor writes: In China I've seen down-counting LED displays for the red sign. But this is just to simple for Europe. Badly. I've certainly seen countdown display for pedestrians in several European cities. They are not used for cars here in Denmark because a certain testosterone driven segment of drivers think they are in pole-position when they see a count-down. -- 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 -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
On 01/17/2012 02:08 AM, li...@lazygranch.com wrote: Correct me if I'm wrong, but UTC gets corrected from time to time, but many things depend on GPS time to be consistent (no jumps), so they can't adjust it. The way the GPS set of gears works, they need a continuous linear time internally. The UTC correction mechanism was added later. It makes sense to create a unique internal time-scale and adjust to external time-scales later. It's not bad to have their own internal time-scale which one has control over, the key aspect lies in being able to relate it to other time-scales in a known and predictable fashion, if needed. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
I think the time jumps would be a problem for the GPS customers. Suppose I am computing speed by differential readings. The jump would be an issue, especially if time went backwards. File stamps. Stock timing. Similar problems. -Original Message- From: Magnus Danielson mag...@rubidium.dyndns.org Sender: time-nuts-boun...@febo.com Date: Tue, 17 Jan 2012 02:30:28 To: time-nuts@febo.com Reply-To: Discussion of precise time and frequency measurement time-nuts@febo.com Subject: Re: [time-nuts] 15 Seconds error...?? On 01/17/2012 02:08 AM, li...@lazygranch.com wrote: Correct me if I'm wrong, but UTC gets corrected from time to time, but many things depend on GPS time to be consistent (no jumps), so they can't adjust it. The way the GPS set of gears works, they need a continuous linear time internally. The UTC correction mechanism was added later. It makes sense to create a unique internal time-scale and adjust to external time-scales later. It's not bad to have their own internal time-scale which one has control over, the key aspect lies in being able to relate it to other time-scales in a known and predictable fashion, if needed. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
On 01/17/2012 03:18 AM, li...@lazygranch.com wrote: I think the time jumps would be a problem for the GPS customers. Suppose I am computing speed by differential readings. The jump would be an issue, especially if time went backwards. File stamps. Stock timing. Similar problems. If you do not desire jumps, do not use UTC time but GPS time out of the receiver. Jumping the internal time-scale would upset things, so a none-jumping time-scale is used. If an application requires a non-jumping time-scale, then use GPS time-scale for that application. Cheers, Magnus ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
On 1/16/12 6:58 PM, Magnus Danielson wrote: On 01/17/2012 03:18 AM, li...@lazygranch.com wrote: I think the time jumps would be a problem for the GPS customers. Suppose I am computing speed by differential readings. The jump would be an issue, especially if time went backwards. File stamps. Stock timing. Similar problems. If you do not desire jumps, do not use UTC time but GPS time out of the receiver. or TAI... Jumping the internal time-scale would upset things, so a none-jumping time-scale is used. If an application requires a non-jumping time-scale, then use GPS time-scale for that application. I just had an discussion last week with people who wrote a spec requiring GMT (copying an older spec that antedated UTC, I suspect). Subtle details of GMT vs UTC are lost on them. When the leap second notice came out I asked what they were going to do (since the logs need to be monotonic and continuous). For now, they'll use the hack of shutting down before UTC midnight on 30 June and starting up later. It turns out that most of the system actually uses TAI/GPS time and hence it isn't a problem, but it's technically non-compliant with the requirement for GMT. So they're stuck: 1) admit the system does not meet the requirement and seek a waiver of the requirement 2) Change the requirement Both are painful. Life would be easier if they just said.. use TAI time. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] 15 Seconds error...??
My description of the problem would have been a thousand times better if I mentioned monotonicity. It is a classical problem with any discrete control system. Nonlinearlity is much easier to handle that missing codes or a lack of monotonicity. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] NTP for 64 bit windows
Has anyone come across a NTP client that uses native 64 Win 7 code? I've noticed all the 64 bit versions are running under WOW. I've use Meinberg now found another source out of Poland. http://sites.google.com/site/ntpserverspl/ntp-server-time-client-64 This is an ugly thing to search since NTP itself makes reference to 64 bits, and non of the programs seem to specify native code. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] NTP for 64 bit windows
Has anyone come across a NTP client that uses native 64 Win 7 code? I've noticed all the 64 bit versions are running under WOW. I've use Meinberg now found another source out of Poland. http://sites.google.com/site/ntpserverspl/ntp-server-time-client-64 This is an ugly thing to search since NTP itself makes reference to 64 bits, and non of the programs seem to specify native code. Thanks for that pointer, Gary. I do wish they said just what the setup.exe is going to install - with some application software I have no alternative except clicking on setup.exe, but with NTP I do feel the need to know more about what elements of my system are going to be altered as I already have a well-tuned NTP setup. Dave Hart has done a lot of work with NTP, including the Windows port, and his most recent work has resulted in very significant performance improvements for NTP 4.2.7p241 and later. These won't yet be in their 4.2.7p32. I also wonder whether their version includes support for the same reference clocks, and the Kernel-mode serial PPS driver which Dave has built. Perhaps Tomasz Widomski and/or p.marszalek should be invited to join either this list or NTP Hackers? Cheers, David -- SatSignal software - quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] NTP for 64 bit windows
Has anyone come across a NTP client that uses native 64 Win 7 code? I've noticed all the 64 bit versions are running under WOW. I've use Meinberg now found another source out of Poland. http://sites.google.com/site/ntpserverspl/ntp-server-time-client-64 I was going to ask, Gary, have you used this software, have you seen any difference between 32-bit and 64-bit operation on Windows? I would have thought that you wouldn't see a lot of difference, but I could be wrong. The lack of visible source files on that site is rather putting me off! Cheers, David -- SatSignal software - quality software written to your requirements Web: http://www.satsignal.eu Email: david-tay...@blueyonder.co.uk ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
