Re: [time-nuts] Beginner's time reference
In a message dated 12/12/2009 05:08:39 GMT Standard Time, john.fo...@gmail.com writes: Time does not just exist. That is correct. It is a human construct, like all other things. We define it, as all other things, and then make useful empirical comparative observations with it. --- It isn't quite as straightforward as that, in the sense that is of time being just a human construct, and not all other things are human constructs either. It's not too unreasonable to accept that events, in conventional physics at least, do generally occur in a sequential fashion, hence the intervals between them that we strive to measure, and that would occur without any human intervention or existence. It's when one attempts to quantify time itself as a measurable quantity in itself that problems arise. There are measurable quantities such as mass, length, potential difference etc, that again aren't human constructs but exist anyway, and would continue to do so even if we and our definitions all disappeared tomorrow. But with time there is no absolute quantity, just those intervals again, so when you say we define it, just how would you attempt to define it as an absolute quantity? Although it's reasonable to accept that we live in a universe where things occur sequentially, even if not necessarilly causually related, and hence the existence of intervals between events can be accepted also, and can be measured in terms of whatever units we choose to define, that still does not demonstrate that time itself actually exists. regards Nigel GM8PZR ___ 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] Beginner's time reference
In a message dated 12/12/2009 08:13:04 GMT Standard Time, charles_steinm...@lavabit.com writes: Time nuts do not and cannot measure time itself because time as an absolute entity just doesn't exist. I suppose specifying the interval since the big bang could qualify as an absolute measure of time (at least in our universe), but in practice it must elude us because everything in the universe is in motion and there is no practical way to relate our frame of reference to any frame with the location of the big bang at the origin. Note that assigning conventional units to measurements does not detract from the ontological existence (or not) of the measured things. Most would agree that physical extent (vector distance) exists, notwithstanding that the units we use to measure it are conventional. -- Again though, it's the interval that we measure. We tend to talk in terms of the passage or flow of time, which gives substance to the concept of time in some way existing as an independent entity, whilst sometimes losing sight of such terms again being only defined in terms of intervals. Assigning conventional units to measurement is not a problem, it's just that the units we assign to time measurement are always a measure of the intervals. There's no problem with this either until one starts to believe, as many seem to do without due consideration, that time itself is an absolute quantity. -- nobody has ever demonstrated the existence of time itself as a measurable quantity. Without intending to expreess a view regarding the ontological status of time, I would point out that one must be careful to distinguish between the ontological question and any practical/empirical questions such as the frame-of-reference issue noted above. The ontological question is murky because it appears that time is an orthogonal component of spacetime, and it can always be disputed under what conditions (if any) the constituent parts of ontological entities are themselves ontological entities. [And, the question presumes that one accepts the ontological existence of spacetime.] But this may be more philosophy than most time nuts want to contend with! - It's interesting though to note that the Ontological Argument, as a more specific term, generally seeks to find a logical basis for the existence of yet another mythical entity:-) I agree it becomes more of a philosophical argument than is sometimes comfortable, and more often than not perhaps a question of etymology rather than ontology as we debate the meanings and definitions of the words we use to describe things, but I do think it's important to stop and consider sometimes just what we do mean, or what is implied, when we talk about time. regards Nigel GM8PZR ___ 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] Beginner's time reference
At 06:47 PM 12/11/2009, gandal...@aol.com wrote... Unfortunately, that's not really the way it is. That's opinion, stated as fact. Time nuts do not and cannot measure time itself because time as an absolute entity just doesn't exist. That depends upon how one defines time. Also, how one defines reality, and where they sit on the philosophical/pragmatic scale. The OED's first definition is the indefinite continued progress of existence and events in the past, present, and future, regarded as a whole, and that's exactly what time nuts measure. Time exists in the same way any other dimension does. It is measured by comparision (how many cycles of Cs resonance between two other events, etc.). Zeno's paradox tells us that distance and motion don't exist, either. But, there they are. No sense trying to respond, since it is impossible for your fingers to travel the distance required to make a response. And just in case anyone wishes to shout me down on this, as happened when I dared to suggest the same some time ago, It's easy to be right, when you define terms to your own liking. Just what do you mean by some time ago, given your claim that time itself [isn't a] measurable quantity? :-) ___ 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] Beginner's time reference
In a message dated 12/12/2009 11:35:49 GMT Standard Time, mi...@flatsurface.com writes: At 06:47 PM 12/11/2009, gandal...@aol.com wrote... Unfortunately, that's not really the way it is. That's opinion, stated as fact. -- Is it? Can you show me any definition of time which demonstrates it to be an absolute quantity other than those which relate only to intervals? Time nuts do not and cannot measure time itself because time as an absolute entity just doesn't exist. That depends upon how one defines time. Also, how one defines reality, and where they sit on the philosophical/pragmatic scale. The OED's first definition is the indefinite continued progress of existence and events in the past, present, and future, regarded as a whole, and that's exactly what time nuts measure. Time exists in the same way any other dimension does. It is measured by comparision (how many cycles of Cs resonance between two other events, etc.). Zeno's paradox tells us that distance and motion don't exist, either. But, there they are. No sense trying to respond, since it is impossible for your fingers to travel the distance required to make a response. --- I think you might be missing the point, the OED definition that you quote does not define time itself as an absolute measurable entity, and what time nuts measure are, yet again, the intervals between events. Dimensions, if you like, are properties rather than absolute entities but generally of something that has physical existence, so a rock, for an example, might be said to have mass, length, height, etc. It doesn't matter how you choose to define the properties, the rock con tinues to exist regardless. Similarly, less tangible items such as perhaps potential difference will exist anyway regardless of our definitions or the dimensions we apply to them. Frequency of course, as in how many cycles, is inversely proprtional to time intervals so back to square one:-) - And just in case anyone wishes to shout me down on this, as happened when I dared to suggest the same some time ago, It's easy to be right, when you define terms to your own liking. Just what do you mean by some time ago, given your claim that time itself [isn't a] measurable quantity? :-) Who said I was defining it to my own liking?, I did say it wasn't always a very comfortable contemplation. Some time ago is easily defined in terms of time intervals, albeit perhaps not to the usual time nuts' standards of precision:-), but that's the whole point, we know that the intervals exist that separate sequential events, and we know we can measure them with significant acuracy, but where does that leave us in terms of time itself. Considering time as a dimension isn't quite so bad but the point I was attempting to make, perhaps not very well, was that many folks choose to, or want to, treat time itself as something that exists in a physical form, such as a river for example, and hence, again just by way of example, something that we might consider travelling backwards and forwards along if only we could find the right boat. And continuing that analogy, if it's the flow of water that creates a river, what is it that flows to create time:-) ? regards Nigel GM8PZR ___ 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] Beginner's time reference
At 07:13 AM 12/12/2009, gandal...@aol.com wrote... I think you might be missing the point, the OED definition that you quote does not define time itself as an absolute measurable entity, and what time nuts measure are, yet again, the intervals between events. Define absolute measurable quantity, and give an example of something (not countable, like fingers on a hand) which is. What units do you measure in? Certainly not most SI units, which vary by reference frame (time, length, mass, current, luminous intensity), and/or are simple counts (mass effectively, mole) - which leaves temperature. How do you measure temperature without using any of the other SI units? How does one measure, if not by comparison? Is pi measurable? Can I measure the circumference of a circle of diameter 1? How? Or are you focused on absolute? If so, how is time any different than distance? You measure between the points you want to measure. I can measure the length of a bar of platinum-iridium, and call that 1 meter, or I can measure the distance a photon travels in 1/299 792 458 of a second. Is one somehow less real than the other? Considering time as a dimension isn't quite so bad but the point I was attempting to make, perhaps not very well, was that many folks choose to, or want to, treat time itself as something that exists in a physical form, such as a river for example, and hence, again just by way of example, something that we might consider travelling backwards and forwards along if only we could find the right boat. Einstein didn't claim time didn't exist - he linked it with space. Time and distance are both relative to the frame of reference. Einstein had no problem making frequent reference to the speed (distance/time) of light. When he said Time is an illusion, it was in reference to time separated from space. That doesn't mean it doesn't exist, or isn't physical. This is nothing new. The GPS system was designed with the understanding that the satellites exist in a different frame of reference than the receivers. Yet, it works, because we measure time and mathematically adjust for the different reference frames. Seems to me you're just being pedantic. It's like claiming Newtonian physics is wrong, even though it works perfectly well for 99.99% of what it's used for. ___ 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] Beginner's time reference
Remember that saying from the Hitchhikers' Guide: Time is an illusion - lunchtime doubly so. ___ 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] Audio recording with time code
Joseph Gray schreef: My first thought was using IRIG on one of the channels. I could buy a copy of NMEATime to generate the IRIG, but then I don't have anything to decode it on playback. I was thinking the same. Are there (freeware) IRIG-B software decoder/display programs using a PC/soundcard? Henry. ___ 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] Beginner's time reference
In a message dated 12/12/2009 13:00:21 GMT Standard Time, mi...@flatsurface.com writes: At 07:13 AM 12/12/2009, gandal...@aol.com wrote... I think you might be missing the point, the OED definition that you quote does not define time itself as an absolute measurable entity, and what time nuts measure are, yet again, the intervals between events. Define absolute measurable quantity, and give an example of something (not countable, like fingers on a hand) which is. What units do you measure in? Certainly not most SI units, which vary by reference frame (time, length, mass, current, luminous intensity), and/or are simple counts (mass effectively, mole) - which leaves temperature. How do you measure temperature without using any of the other SI units? How does one measure, if not by comparison? Is pi measurable? Can I measure the circumference of a circle of diameter 1? How? Or are you focused on absolute? If so, how is time any different than distance? You measure between the points you want to measure. I can measure the length of a bar of platinum-iridium, and call that 1 meter, or I can measure the distance a photon travels in 1/299 792 458 of a second. Is one somehow less real than the other? Only focussed on absolute inasmuch as that was what I was referring to in the first place and you're still mising the point. Time, as a distance if you wish between two points, is measurable as the duration of the interval, no problem with that, but whereas your platinum-iridium bar continues to exist outside of your measurement of its properties the same cannot be said of any particular interval between events. Considering time as a dimension isn't quite so bad but the point I was attempting to make, perhaps not very well, was that many folks choose to, or want to, treat time itself as something that exists in a physical form, such as a river for example, and hence, again just by way of example, something that we might consider travelling backwards and forwards along if only we could find the right boat. Einstein didn't claim time didn't exist - he linked it with space. Time and distance are both relative to the frame of reference. Einstein had no problem making frequent reference to the speed (distance/time) of light. When he said Time is an illusion, it was in reference to time separated from space. That doesn't mean it doesn't exist, or isn't physical. -- Perhaps I should have been a bit more specific. One quote, which was actually attributed to Freeman Dyson when discussing the difference in approach between Poincare and Einstein commented His version of the theory was simpler and more elegant. There was no absolute space and time and there was no ether.. It was only an off the cuff comment anyway so not particularly relevant to my argument as such, but please do explain in what way time itself might be physical -- This is nothing new. The GPS system was designed with the understanding that the satellites exist in a different frame of reference than the receivers. Yet, it works, because we measure time and mathematically adjust for the different reference frames. Seems to me you're just being pedantic. It's like claiming Newtonian physics is wrong, even though it works perfectly well for 99.99% of what it's used for. -- Call me pedantic if you wish, but it has nothing at all to do with claiming that Newtonian physics is wrong, which I'm not, even though that it can have its limitations. I'm sorry you can't, or won't, understand but the ability to measure intervals between events does not in itself demonstrate the existence of time as any kind of physical entity. If we can only define time in terms of the interval between events then so be it, but isn't that just where we came in? Is it possible that flatsurface might be synonymous with flatearth?:-) regards Nigel GM8PZR ___ 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] Beginner's time reference
At 08:53 AM 12/12/2009, gandal...@aol.com wrote... I'm sorry you can't, or won't, understand but the ability to measure intervals between events does not in itself demonstrate the existence of time as any kind of physical entity. LOL. You're over your head here. ___ 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] Beginner's time reference
Give it to them Nigel . . . . . Roy -- From: gandal...@aol.com Sent: Friday, December 11, 2009 11:47 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Beginner's time reference In a message dated 11/12/2009 21:47:28 GMT Standard Time, michael.c...@wanadoo.fr writes: For me time just exists. What time nuts do is to try and measure and characterise it. Unfortunately, that's not really the way it is. Time nuts do not and cannot measure time itself because time as an absolute entity just doesn't exist. We can measure the length of the intervals between events, time intervals if you choose to call them that, but nobody has ever demonstrated the existence of time itself as a measurable quantity. And just in case anyone wishes to shout me down on this, as happened when I dared to suggest the same some time ago, I have since been heartened to read in Walter Isaacson's excellent biography that a certain Mr Einstein arrived at the same conclusion. We could of course both be wrong, but at least I'll be wrong in good company:-) regards Nigel GM8PZR ___ 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] Beginner's time reference
Here's another way to look at it: Time is what keeps things from happening all at once. Also, without time there can be no motion (velocity, acceleration x time). The units of distance are arbitrary - from the King's foot to a chosen number of atomic wavelengths. And so the units of time are arbitrary - fractions of the rotation of the Earth. Distance exists and time exists, but the measure of things is man - in the sense that without man, there would be no units of measurement. I may measure time with a clock, but I can't characterize time. I can only compare and characterize man's instruments for measuring time. Maybe it's like people's perception of Evolution. Some see it as a thing that causes things to be the way they are. Others know that evolution is a process that describes what happens to genes in changing environments. Oh, I am collapsing under the weight of these heavy thoughts . . . Bill Hawkins -Original Message- From: gandal...@aol.com Sent: Friday, December 11, 2009 11:47 PM To: time-nuts@febo.com Subject: Re: [time-nuts] Beginner's time reference In a message dated 11/12/2009 21:47:28 GMT Standard Time, michael.c...@wanadoo.fr writes: For me time just exists. What time nuts do is to try and measure and characterise it. Unfortunately, that's not really the way it is. Time nuts do not and cannot measure time itself because time as an absolute entity just doesn't exist. We can measure the length of the intervals between events, time intervals if you choose to call them that, but nobody has ever demonstrated the existence of time itself as a measurable quantity. And just in case anyone wishes to shout me down on this, as happened when I dared to suggest the same some time ago, I have since been heartened to read in Walter Isaacson's excellent biography that a certain Mr Einstein arrived at the same conclusion. We could of course both be wrong, but at least I'll be wrong in good company:-) regards Nigel GM8PZR ___ 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] Beginner's time reference
On Sat, Dec 12, 2009 at 6:33 AM, Mike S mi...@flatsurface.com wrote: At 06:47 PM 12/11/2009, gandal...@aol.com wrote... Unfortunately, that's not really the way it is. That's opinion, stated as fact. That all depends on what your definition of is is :-) ___ 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] Invariance
If from relativity theory time is NOT considered invariant, would frequency (in terms of the output of a cesium standard or hydrogen maser) be considered invariant? Bruce Hunter ___ 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] Audio recording with time code
On 12/12/09 5:45 AM, Henry Vredegoor henry.vredeg...@gmail.com wrote: Joseph Gray schreef: My first thought was using IRIG on one of the channels. I could buy a copy of NMEATime to generate the IRIG, but then I don't have anything to decode it on playback. I was thinking the same. Are there (freeware) IRIG-B software decoder/display programs using a PC/soundcard? Henry. Google is your friend I think there's one that is part of NTP http://www.eecis.udel.edu/~mills/ntp/html/drivers/driver6.html http://www.dolben.org/IRIG.php is another Here's one as a LabView .vi that runs on one of their FPGA cards that may provide a basis: http://zone.ni.com/devzone/cda/epd/p/id/3396 And, in a message from 2004 on this list, Dean Weiten comments The standard source package for the Network Time Protocol package, found either at http://www.ntp.org or through download with/for a LINUX distribution, has a tool in the utils directory called tg, which stands for tone generator. It can generate simple modulated IRIG-B and WWV(H) time signals on an audio card. Unfortunately, I found that it would not compile for X86 - it was apparently written for the SparcStation, I think. I've modified it to work with Open Sound System (a modern LINUX sound system), and added all kinds of IRIG options, including IEEE 1344 yes/no, daylight savings time, proper second-of-day, 1998 or 2002 format (includes years), etc. I also tweaked the WWV(H) format to make it more correct, e.g. skipping the 440 Hz tone on the 29th second, etc. ___ 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] Beginner's time reference
In a message dated 12/12/2009 15:17:23 GMT Standard Time, mi...@flatsurface.com writes: At 08:53 AM 12/12/2009, gandal...@aol.com wrote... I'm sorry you can't, or won't, understand but the ability to measure intervals between events does not in itself demonstrate the existence of time as any kind of physical entity. LOL. You're over your head here. -- If you say so. Closed minds are always difficult to communicate with so I think I'll just give up on this one. regards Nigel GM8PZR ___ 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] Beginner's time reference
Whoah I can imagine this kind of debate over a soccer/hockey/insert your sport here/ team, but on the nature of time? unless I am missing some irony? - Original Message - From: gandal...@aol.com To: time-nuts@febo.com Sent: Saturday, December 12, 2009 5:17 PM Subject: Re: [time-nuts] Beginner's time reference In a message dated 12/12/2009 15:17:23 GMT Standard Time, mi...@flatsurface.com writes: At 08:53 AM 12/12/2009, gandal...@aol.com wrote... I'm sorry you can't, or won't, understand but the ability to measure intervals between events does not in itself demonstrate the existence of time as any kind of physical entity. LOL. You're over your head here. -- If you say so. Closed minds are always difficult to communicate with so I think I'll just give up on this one. regards Nigel GM8PZR ___ 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. No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.427 / Virus Database: 270.14.104/2560 - Release Date: 12/12/09 07:38:00 ___ 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] Beginner's time reference
Well, here's another statement that reveals the nature of time: Time flies like an arrow. Fruit flies like a banana. Bill Hawkins ___ 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] Beginner's time reference
At 12:41 PM 12/12/2009, Ian Sheffield wrote... I can imagine this kind of debate over a soccer/hockey/insert your sport here/ team, but on the nature of time? unless I am missing some irony? He's either having a very hard time stating something very obvious (and behaving as if it's insightful), or incorrectly parroting something he doesn't understand. He claims Time nuts do not and cannot measure time itself because time as an absolute entity just doesn't exist. That's the same as saying one can't measure distance, because space doesn't exist. Bollocks. Alternately, he simply means there is no universal epoch for time, so just as a spacial coordinate requires a defined reference, so too does a time measurement. So, there's nothing unique about time, or our measurement of it, in that regard, and no insight. Since we live in spacetime, that's entirely expected. He's refused to define his terms, and can't give an example of something which _is_ measurable (in units other than spacetime), so he seems simply to be arguing about angels on pinheads. Of course spacetime exists. It's where we (and all other energymatter) live. ___ 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] Beginner's time reference
Some (Penrose, Nottale) suggest that time may be discrete rather than continuous. 10E-43 second might be your basic tick. Mike S wrote: Alternately, he simply means there is no universal epoch for time, so just as a spacial coordinate requires a defined reference, so too does a time measurement. So, there's nothing unique about time, or our measurement of it, in that regard, and no insight. Since we live in spacetime, that's entirely expected. ___ 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] Beginner's time reference
I can not see how time is any different to any other quantity in Maxwell's equations, so time must be just as measurable, real and physical. cheers, Neville Michie ___ 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] LORAN C simulator operational
Back from a trip and have had a chance to clean up the software for the LORAN C simulator. So do people generally just attach that to this thread. Say a schematic and basic program. Then thats it??? The simulators very stable and at this point the Austron 2100F goes from acquire to track in about 2 minutes. With the first readout at 1.1 e-11 between the two references that I am using. I am using a gri of 6 though others can be used. Signal level 48 which is quite strong. By the way schematic wise I suspect final output a gif. Any particular free schematic software people use. I am comfortable with visio so may just use that. Reagrds On Tue, Dec 8, 2009 at 2:48 PM, paul swed paulsw...@gmail.com wrote: A few weeks back I started a discussion on the demise of LORAN C. It was quite a long discussion and spawned several others. I will indeed miss LORAN C as a frequency reference for several reasons. It was very good more stable then wwvb on the east coast. And for 10 years I have had 3 austron 2100 and 2100f frequency monitors. I used LORAN C to set my RB standards. Granted I also have GPS using the hp 3801. So with the shutdown in Jan I hated junking the Austrons they are nice comparators. Recently, 2 days ago I set out to see if a LORAN C simulator could be created that was simple, effective, and inexpensive. Using very common parts and minimum of wiring. It would appear that it can be done. What I am using is 5 cmos chips CD 4000 series gates and counters and a parallax SXb micro programmed in basic. These have allowed me to emulate the master stations and the GRIs along with the phase reversals needed to identify a master. Using 2 RB standards a HP5065a as the master to the simulator and a cel tower RB pull and both had been set to LORAN C and checked with GPS the austrons tracking the simulated LORAN signal in 1-7 E-12th range as expected. This is very fresh data as this has been running about 5 hours now and there could be issues. More time is needed to cleanup the software about 100 lines of easy code thats simple and consistent in operation. (Read this as not tricky and really boring) Other comments the waveform is simple no attempt has been made to actually create the wave shape. (Part of the KISS principle) I really wanted to see what I could get away with. Still do wonder if I need the phase reversals. Now if there is interest I will need to figure out how to share the details and code. Will be on a business trip for the next few days so may not see a reply. Regards Paul ___ 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] Beginner's time reference
At 05:02 PM 12/12/2009, Mike Naruta AA8K wrote... Some (Penrose, Nottale) suggest that time may be discrete rather than continuous. 10E-43 second might be your basic tick. Yes, Planck time. Closer to 5.4e-44 s. ___ 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] LORAN C simulator operational
Hi Paul: Glad to hear it's working! Free schematic software at: http://www.expresspcb.com/ They also have PCB layout that's tied to the schematic and very reasonable prices for making boards. No interest in the company other than being a happy user. Have Fun, Brooke Clarke http://www.PRC68.com paul swed wrote: Back from a trip and have had a chance to clean up the software for the LORAN C simulator. So do people generally just attach that to this thread. Say a schematic and basic program. Then thats it??? The simulators very stable and at this point the Austron 2100F goes from acquire to track in about 2 minutes. With the first readout at 1.1 e-11 between the two references that I am using. I am using a gri of 6 though others can be used. Signal level 48 which is quite strong. By the way schematic wise I suspect final output a gif. Any particular free schematic software people use. I am comfortable with visio so may just use that. Reagrds On Tue, Dec 8, 2009 at 2:48 PM, paul swedpaulsw...@gmail.com wrote: A few weeks back I started a discussion on the demise of LORAN C. It was quite a long discussion and spawned several others. I will indeed miss LORAN C as a frequency reference for several reasons. It was very good more stable then wwvb on the east coast. And for 10 years I have had 3 austron 2100 and 2100f frequency monitors. I used LORAN C to set my RB standards. Granted I also have GPS using the hp 3801. So with the shutdown in Jan I hated junking the Austrons they are nice comparators. Recently, 2 days ago I set out to see if a LORAN C simulator could be created that was simple, effective, and inexpensive. Using very common parts and minimum of wiring. It would appear that it can be done. What I am using is 5 cmos chips CD 4000 series gates and counters and a parallax SXb micro programmed in basic. These have allowed me to emulate the master stations and the GRIs along with the phase reversals needed to identify a master. Using 2 RB standards a HP5065a as the master to the simulator and a cel tower RB pull and both had been set to LORAN C and checked with GPS the austrons tracking the simulated LORAN signal in 1-7 E-12th range as expected. This is very fresh data as this has been running about 5 hours now and there could be issues. More time is needed to cleanup the software about 100 lines of easy code thats simple and consistent in operation. (Read this as not tricky and really boring) Other comments the waveform is simple no attempt has been made to actually create the wave shape. (Part of the KISS principle) I really wanted to see what I could get away with. Still do wonder if I need the phase reversals. Now if there is interest I will need to figure out how to share the details and code. Will be on a business trip for the next few days so may not see a reply. Regards Paul ___ 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] Beginner's time reference
There is at least one thing that you cannot do with time, which you can do with pretty much everything else: you cannot go back and recheck your measurement. ... I'll let the thinkers think about that one, while I will have another scoop of ice-cream before it melts (time, time) Didier -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Neville Michie Sent: Saturday, December 12, 2009 4:03 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] Beginner's time reference I can not see how time is any different to any other quantity in Maxwell's equations, so time must be just as measurable, real and physical. cheers, Neville Michie ___ 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] 60Hz mains clocking in computers
I'm trying to get to the bottom of whether or not any computing equipment made around the advent of UNIX systems (or any time-slicing system) used the mains cycles of 60Hz as phase lock for the internal system clock. My guess is that perhaps they did not as the computing logic is DC based, but, I have memories of using an 68000 based UNIX system that I thought had its internal clock based off of the 60Hz mains... Not sure the vendor anymore. Thanks, Colby ___ 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] Invariance
Some researches is about to measure the change of universal constants as universe expands. Time and Spacetime: The Crystallizing Block Universe http://arxiv.org/abs/0912.0808 The nature of the future is completely different from the nature of the past. When quantum effects are significant, the future shows all the signs of quantum weirdness, including duality, uncertainty, and entanglement. With the passage of time, after the time-irreversible process of state-vector reduction has taken place, the past emerges, with the previous quantum uncertainty replaced by the classical certainty of definite particle identities and states. The present time is where this transition largely takes place, but the process does not take place uniformly: Evidence from delayed choice and related experiments shows that isolated patches of quantum indeterminacy remain, and that their transition from probability to certainty only takes place later. Thus, when quantum effects are significant, the picture of a classical Evolving Block Universe (`EBU') cedes place to one of a Crystallizing Block Universe (`CBU'), which reflects this quantum transition from indeterminacy to certainty, while nevertheless resembling the EBU on large enough scales. - George F. R. Ellis, Tony Rothman (Submitted on 4 Dec 2009) -- http://www.wearablesmartsensors.com/ http://www.softwaresafety.net/ http://www.designer-iii.com/ http://www.unusualresearch.com/ ___ 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] 60Hz mains clocking in computers
On 12/12/09 5:29 PM, Colby Gutierrez-Kraybill co...@astro.berkeley.edu wrote: I'm trying to get to the bottom of whether or not any computing equipment made around the advent of UNIX systems (or any time-slicing system) used the mains cycles of 60Hz as phase lock for the internal system clock. My guess is that perhaps they did not as the computing logic is DC based, but, I have memories of using an 68000 based UNIX system that I thought had its internal clock based off of the 60Hz mains... Not sure the vendor anymore. There were a variety of computers synchronized not to the mains frequency but to the horizontal retrace or vertical frame rate for video. That way, they could do things like DRAM refresh or video buffer updates in a clock synchronous way. To a certain extent, even the IBM PC was built like this, running at 4.77 MHz, divided down by 3 from a 14.3 MHz crystal (which was divided by 4 to get the 3.58 MHz color burst). If I had to guess, at the low end, boxes like the Atari 68K machines, at the high end, 3Rivers PERQ (but that one sticks as using 2901 bitslice...) Anything intended to generate video for integration with other video streams would greatly benefit from being able to be synchronized to the NTSC 59.95 Hz frame rate, and if the video memory is the same as the system ram, then running the CPU clock at an exact multiple makes designing the memory access arbiters easier (they can be synchronous), so what you really want is the pixel rate being a multiple of 59.95 and the CPU clock being a multiple of the pixel rate, so that wait state generation is easy (or you can do transparent/hidden access to RAM during a time when you KNOW the CPU won't be looking at it). More than one system used the video access to do DRAM refresh, too. ___ 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] 60Hz mains clocking in computers
Not Linux but cpm, I think the poly 88 a 6 slot s-100 computer used the mains for the RTC that is a diode from the secondary of the main power transformer to an interrupt on the processor a 8080. Sure that was used for other computer Real Time Clocks but don't remember any processor clock based on the mains. Stanley - Original Message From: Colby Gutierrez-Kraybill co...@astro.berkeley.edu To: time-nuts@febo.com Sent: Sat, December 12, 2009 7:29:17 PM Subject: [time-nuts] 60Hz mains clocking in computers I'm trying to get to the bottom of whether or not any computing equipment made around the advent of UNIX systems (or any time-slicing system) used the mains cycles of 60Hz as phase lock for the internal system clock. My guess is that perhaps they did not as the computing logic is DC based, but, I have memories of using an 68000 based UNIX system that I thought had its internal clock based off of the 60Hz mains... Not sure the vendor anymore. Thanks, Colby ___ 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] 60Hz mains clocking in computers
co...@astro.berkeley.edu said: I'm trying to get to the bottom of whether or not any computing equipment made around the advent of UNIX systems (or any time-slicing system) used the mains cycles of 60Hz as phase lock for the internal system clock. The IBM 360s bumped a memory location each cycle of the power line. They bumped it by 6 in 50 HZ countries and by 5 in 60 HZ countries. So the units were 300ths of a second. I think that was used for the system time-of-day clock. (I assume it was a few lines of microcode.) My guess is that perhaps they did not as the computing logic is DC based, but, I have memories of using an 68000 based UNIX system that I thought had its internal clock based off of the 60Hz mains... Not sure the vendor anymore. I'm not sure what DC based means. For something like this, you would need an IO device that generated an interrupt. It's a pretty simple IO device, but as far as the CPU is concerned, the power line is part of the outside world. Most of the hardware for this sort of IO device would probably be filtering out noise. -- These are my opinions, not necessarily my employer's. I hate spam. ___ 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] 60Hz mains clocking in computers
Talk about dusting of the old brain cells. I seem to remember that the PDP 11/23s did indeed allow the use of the 60 hz as an interrupt for precision timing if that can actually be said. The data general nova 1200 also. Boy thats exposing ones age. On Sat, Dec 12, 2009 at 8:29 PM, Colby Gutierrez-Kraybill co...@astro.berkeley.edu wrote: I'm trying to get to the bottom of whether or not any computing equipment made around the advent of UNIX systems (or any time-slicing system) used the mains cycles of 60Hz as phase lock for the internal system clock. My guess is that perhaps they did not as the computing logic is DC based, but, I have memories of using an 68000 based UNIX system that I thought had its internal clock based off of the 60Hz mains... Not sure the vendor anymore. Thanks, Colby ___ 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] 60Hz mains clocking in computers
Yes, the whole PDP-11 line used line frequency to update the real-time clock. DEC had a real-time operating system, very useful for emulation of analog process control functions. Of course, an RTOS is more than just the clock. We lost that anchor to real time in the interval between the PDP-11 and NTP or SNTP when the microprocessors took over. All crystal clocks; time of day (social time) set by anybody with a wristwatch. Bill Hawkins -Original Message- From: paul swed Sent: Saturday, December 12, 2009 10:09 PM Talk about dusting off the old brain cells. I seem to remember that the PDP 11/23s did indeed allow the use of the 60 hz as an interrupt for precision timing if that can actually be said. The data general nova 1200 also. Boy thats exposing ones age. On Sat, Dec 12, 2009 at 8:29 PM, Colby Gutierrez-Kraybill co...@astro.berkeley.edu wrote: I'm trying to get to the bottom of whether or not any computing equipment made around the advent of UNIX systems (or any time-slicing system) used the mains cycles of 60Hz as phase lock for the internal system clock. My guess is that perhaps they did not as the computing logic is DC based, but, I have memories of using an 68000 based UNIX system that I thought had its internal clock based off of the 60Hz mains... Not sure the vendor anymore. Thanks, Colby ___ 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] Beginner's time reference
Nigel wrote: Again though, it's the interval that we measure. [In response to my suggestion that, in theory, we could specify the interval since the big bang and it would be absolute in a fairly robust sense, at least in this universe.] Assigning conventional units to measurement is not a problem, it's just that the units we assign to time measurement are always a measure of the intervals. There's no problem with this either until one starts to believe, as many seem to do without due consideration, that time itself is an absolute quantity. I agree it becomes more of a philosophical argument than is sometimes comfortable, and more often than not perhaps a question of etymology rather than ontology as we debate the meanings and definitions of the words we use to describe things, but I do think it's important to stop and consider sometimes just what we do mean, or what is implied, when we talk about time. This is getting old, but I'll give it one more try. What you allude to in the last paragraph above -- taking care to separate all semantic issues from genuine philosophical issues -- is, as I see it, the heart of this discussion. And it appears to me that you are conflating semantic issues with genuine philosophical issues. I think we all agree that intervals are what we measure. The question is whether this has any bearing on whether time is an absolute quantity, and if so, whether time being or not being an absolute quantity is philosophically interesting. A number of us have been trying, without success, to get you to be more precise about what you mean by time being [or not being] an absolute quantity, and how that might be important. As it stands, you have not done so, so we are left to guess what meaning and import this phrase has in your view. The two possibilities I see are that you mean (i) time has no ontological status -- that is, that it doesn't really exist, but is merely an imaginary construct that we impose on the universe; or (ii) even if time does have ontological status, it is not philosophically interesting unless it is absolute (whatever that means). What a number of us have been saying is that the way we measure time is purely conventional (and therefore, I suppose, imaginary), but that accepting this says nothing about either of these two issues -- i.e., whether time really exists or whether it is philosophically interesting. I take no position on the ontological status of time, but not because we measure it only in intervals or because it is not absolute (whatever that means). Rather, for me, it is an issue whether time -- as one dimension of spacetime -- can be a separate ontological entity. In my view, when Einstein, Dirac, Bohr, Lorentz, Schroedinger, and other founding fathers of modern physics spoke or wrote regarding the existence of time, this is the issue they were addressing. However, if we accept that spacetime exists, nothing is really riding on whether time is a separate ontological entity -- it has ontological status as a constituent of spacetime. So, the remaining question is whether the claim that time is not absolute (whatever that means) -- if true -- somehow renders the issue of time a merely semantic matter, or otherwise philosophically uninteresting. I don't see how this could be, but then I cannot imagine what you mean by time not being absolute, other than it can only be measured by intervals, and you have not explained what you mean in any but the most vague and circular terms. If you are able to articulate what it would be for time to be an absolute quantity, and how this would make a difference with respect to its ontological status or philosophical interest, I'll be happy to listen -- but I won't hold my breath. Best regards, Charles ___ 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] 60Hz mains clocking in computers
In message 3058527a-cc99-4174-be75-21dd92334...@astro.berkeley.edu, Colby Gut ierrez-Kraybill writes: I'm trying to get to the bottom of whether or not any computing equipment made around the advent of UNIX systems (or any time-slicing system) used the mains cycles of 60Hz as phase lock for the internal system clock. They sure did. Digitals PDP computers had a counter register which counted mains-cycles as the only sort of real-time-clock. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe 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.
Re: [time-nuts] 60Hz mains clocking in computers
I'm not so sure about the Nova 1200. I think all the Novas had the RTC was on a standard I/O board, along with the serial interface, PTR, PTP. I remember two crystals, one 16.000 KHz for the clock. The other was for the Baud Rate generator, somewhere about 1 MHz. A minimal system had 3 cards (CPU, Memory, and I/O) -John = Talk about dusting of the old brain cells. I seem to remember that the PDP 11/23s did indeed allow the use of the 60 hz as an interrupt for precision timing if that can actually be said. The data general nova 1200 also. Boy thats exposing ones age. On Sat, Dec 12, 2009 at 8:29 PM, Colby Gutierrez-Kraybill co...@astro.berkeley.edu wrote: I'm trying to get to the bottom of whether or not any computing equipment made around the advent of UNIX systems (or any time-slicing system) used the mains cycles of 60Hz as phase lock for the internal system clock. My guess is that perhaps they did not as the computing logic is DC based, but, I have memories of using an 68000 based UNIX system that I thought had its internal clock based off of the 60Hz mains... Not sure the vendor anymore. Thanks, Colby ___ 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.
