Re: [time-nuts] 60 Hz line quirks, anybody recognize this stuff?
On Mon, 03 Sep 2012 12:00:53 -0500, Graham / KE9H time...@austin.rr.com wrote: On 9/1/2012 1:35 AM, Hal Murray wrote: The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png Hal: Two ideas: 1.) You could have some process in Windows that is causing aperiodic blocking of the OS's ability to process real time data. Can be many, many causes. It is very common for a lot of the background processes that autonomously run when you are not actively using the mouse and keyboard to cause these type of problems. Back up utilities, virus checkers, USB WiFi accessories, are examples. (The worst I have seen was the little CPU inside a (Dell) laptop battery, hanging up the USB bus, every time while it calculated the charge in the battery.) Windows is NOT a real time operating system. A fast computer that is not heavily loaded can come close, but there is a lot of background stuff going on in Windows that can aperiodically hang up a lightly loaded machine. Download a DPC tester (Deferred Procedure Call tester) and watch it for an extended time that includes one of your power glitches. http://www.thesycon.de/deu/latency_check.shtml You can add to this list the SMM (system management mode) routines stored in the BIOS. If those are causing the problem then the OS latency performance becomes academic. I have had to qualify motherboards and BIOS revisions before to avoid problems with them. http://en.wikipedia.org/wiki/System_Management_Mode#Problems ___ 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] 60 Hz line quirks, anybody recognize this stuff?
On 09/03/2012 12:00 PM, Graham / KE9H wrote: On 9/1/2012 1:35 AM, Hal Murray wrote: The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png Hal: Two ideas: 1.) You could have some process in Windows that is causing aperiodic blocking of the OS's ability to process real time data. Can be many, many causes. Hmmm - but wouldn't that result in missing samples and an abrupt phase jump? The waveforms reported appear phase continuous (right number of samples) but the sample values are somehow forced to a constant value. I would guess that the waveform being sampled actually looks like that. attachment: smither.vcf___ 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] 60 Hz line quirks, anybody recognize this stuff?
Hal The power company switches capacitors in and out of the system to help correct bad power factors and this creates glitches. In addition, they also make frequency corrections from time to time. These kinds of corrections occur all the time and at times the power company will change their distribution of power pattern and where you had minimal glitches, you now can have an increase in numbers. Monitoring the power directly from the power line as opposed to the wall wort should or can look the same. But a direct power analysis should point you in proper direction to figure out your problem. Joe k3wry In a message dated 9/3/2012 5:12:46 P.M. Eastern Daylight Time, smit...@c-c-i.com writes: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png ___ 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] 60 Hz line quirks, anybody recognize this stuff?
On 09/03/2012 11:11 PM, Bob Smither wrote: On 09/03/2012 12:00 PM, Graham / KE9H wrote: On 9/1/2012 1:35 AM, Hal Murray wrote: The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png Hal: Two ideas: 1.) You could have some process in Windows that is causing aperiodic blocking of the OS's ability to process real time data. Can be many, many causes. Hmmm - but wouldn't that result in missing samples and an abrupt phase jump? The waveforms reported appear phase continuous (right number of samples) but the sample values are somehow forced to a constant value. I would guess that the waveform being sampled actually looks like that. Indeed. What I was stroked by was the repetitive levels and their tendency (except for one case) to strive towards zero with a small slope. For me the source is in the analogue domain rather than digital domain. Phase continuity and restoration of phase rather implies disturbance of the analogue signal, and the fault behaviour looks like some form of intermittent glitch and discharge mechanism. Try to see if you can find some intermittent part of the design. 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] 60 Hz line quirks, anybody recognize this stuff?
Thanks for all the hints and suggestion. The problem seems to be anRS-232 receiver. I haven't seen any glitches like those since I moved the PPS line to a different PC. Has anybody seen anything like that before? Anybody got any ideas on how a receiver can turn into a driver? The typical level shifters have separate receivers and transmitters rather than a tri-state and enable. Maybe I'll take it apart and see what chip it uses. There is a 1K resistor in series with the output of the wall wart so it makes some sense if a current/slew limited (aka weak) driver got turned on. Looks like I got a lemon in that box. (That's the box that has crazy stuff on the audio input like this: http://www.megapathdsl.net/~hmurray/time-nuts/li ne/2012-Aug-07-a0.png) Anyway, I'm back to looking at things that seem reasonable. Sometimes, glitches happen when the line voltage changes. Here are a few graphs: Here is a sample voltage change: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-b0.png These are the beginning and end of the above: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-b1.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-b2.png A pair of glitches that were close together: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-c1.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-c2.png Isolated glitches: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-03-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-03-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-03-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-03-d0.png -- These are my opinions. 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] 60 Hz line quirks, anybody recognize this stuff?
At a quick look, those look plausible line transients. However, the actual plots look badly undersampled during the transients. The plotted results in the transient areas are pretty meaningless, IMO. YMMV, -John Thanks for all the hints and suggestion. The problem seems to be anRS-232 receiver. I haven't seen any glitches like those since I moved the PPS line to a different PC. Has anybody seen anything like that before? Anybody got any ideas on how a receiver can turn into a driver? The typical level shifters have separate receivers and transmitters rather than a tri-state and enable. Maybe I'll take it apart and see what chip it uses. There is a 1K resistor in series with the output of the wall wart so it makes some sense if a current/slew limited (aka weak) driver got turned on. Looks like I got a lemon in that box. (That's the box that has crazy stuff on the audio input like this: http://www.megapathdsl.net/~hmurray/time-nuts/li ne/2012-Aug-07-a0.png) Anyway, I'm back to looking at things that seem reasonable. Sometimes, glitches happen when the line voltage changes. Here are a few graphs: Here is a sample voltage change: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-b0.png These are the beginning and end of the above: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-b1.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-b2.png A pair of glitches that were close together: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-c1.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-c2.png Isolated glitches: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-02-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-03-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-03-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-03-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-03-d0.png -- These are my opinions. 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. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
j...@quikus.com said: At a quick look, those look plausible line transients. However, the actual plots look badly undersampled during the transients. The plotted results in the transient areas are pretty meaningless, IMO. I agree. I'm sampling at 16 bits, 8K samples per second, mono. I tried 8 bits. It wasn't enough. I picked 8K out of the air. It's a compromise between getting enough data and chewing up disk space. It's good enough for 60 Hz and would probably be good enough to show me the next layer of glitches. 2*8K*86400 is 1.38 gigabytes per day. I've got enough disk space so I can run that for a week or two without having to do serious housecleaning. -- These are my opinions. 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.
[time-nuts] 60 Hz line quirks, anybody recognize this stuff?
The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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] 60 Hz line quirks, anybody recognize this stuff?
On 8/31/12 11:35 PM, Hal Murray wrote: The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png Interesting.. a 2-5 millisecond cutout. And very sharp edged. That's what's weird.. if it were something in the electrical distribution/transmission system, I don't know that it would be that clean (after all, the power line is a moderately effective low pass filter) And it also doesn't look like switching from one source to another. That is, the signal looks phase continuous. Are the gaps 1/6 or 1/12th cycle long? (thinking here of an 3phase inverter with an intermittent switching device) I wonder if the line goes open or to zero? ___ 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] 60 Hz line quirks, anybody recognize this stuff?
IMO, you have an instrumentation issue. I don't think the power grid can do anything like that. YMMV, -John === The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
I agree: I don't think this is possible on a power line. Better to use a second sampling unit to check. On Sat, Sep 1, 2012 at 3:30 PM, J. Forster j...@quikus.com wrote: IMO, you have an instrumentation issue. I don't think the power grid can do anything like that. YMMV, -John === The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
I'd try to beg or borrow a line dsturbance monitor. To me, it looks like a SW issue, BTW. Perhaps something like an interrupt service routine crock. FWIW, -John == I agree: I don't think this is possible on a power line. Better to use a second sampling unit to check. On Sat, Sep 1, 2012 at 3:30 PM, J. Forster j...@quikus.com wrote: IMO, you have an instrumentation issue. I don't think the power grid can do anything like that. YMMV, -John === The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
More... You might try logging the output of an audio oscillator, Even an HP 20 would work. -John = I agree: I don't think this is possible on a power line. Better to use a second sampling unit to check. On Sat, Sep 1, 2012 at 3:30 PM, J. Forster j...@quikus.com wrote: IMO, you have an instrumentation issue. I don't think the power grid can do anything like that. YMMV, -John === The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
More... OOPS You might try logging the output of an audio oscillator, Even an HP 200 would work. -John = I agree: I don't think this is possible on a power line. Better to use a second sampling unit to check. On Sat, Sep 1, 2012 at 3:30 PM, J. Forster j...@quikus.com wrote: IMO, you have an instrumentation issue. I don't think the power grid can do anything like that. YMMV, -John === The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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. ___ 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. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
I concur with John, the grid doesn't do that. To me it looks like line noise and/or a software issue is causing your setup to give false results.I have seen a lot of instrumentation get fooled by line noise, especially around zero crossings. Measuring the power line accurately in the presence of all the variations and possible kinds of noise and phase shifts turns out to be more difficult than it seems at first. Peter On 9/1/2012 9:30 AM, J. Forster wrote: IMO, you have an instrumentation issue. I don't think the power grid can do anything like that. YMMV, -John === The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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. ___ 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 message. Checked by AVG - www.avg.com Version: 10.0.1424 / Virus Database: 2437/5240 - Release Date: 09/01/12 ___ 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] 60 Hz line quirks, anybody recognize this stuff?
IMO, you have an instrumentation issue. I don't think the power grid can do anything like that. YMMV, -John I agree. If this was happening on the grid by the time this blip had traveled down the line to you it would have been so filtered through transformers and other devices and you wouldn't see sharp edges on the waveform but see a slightly rounded distorted waveform, not the sharp transitions you are seeing. If it isn't your test equipment then it is still something local to you like a loose electrical connection in your house momentarily causing your voltage to drop and then it arcs to reconnect the power. If you use an AM radio (not use a radio in the A.M. ;-) ), you could hear this as static or clicks as you observe this waveform on the screen. -Arthur ___ 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] 60 Hz line quirks, anybody recognize this stuff?
I think monitoring a signal generator was the best idea presented. You always need a baseline (sanity) test in any experiment. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
On 9/1/12 6:56 AM, Arthur Dent wrote: IMO, you have an instrumentation issue. I don't think the power grid can do anything like that. YMMV, -John I agree. If this was happening on the grid by the time this blip had traveled down the line to you it would have been so filtered through transformers and other devices and you wouldn't see sharp edges on the waveform but see a slightly rounded distorted waveform, not the sharp transitions you are seeing. If it isn't your test equipment then it is still something local to you like a loose electrical connection in your house momentarily causing your voltage to drop and then it arcs to reconnect the power. If you use an AM radio (not use a radio in the A.M. ;-) ), you could hear this as static or clicks as you observe this waveform on the screen. Do you have a triac/scr switch somewhere upstream? Like an X-10 module or something? Or a remote power controller with a solid state relay? That sharp edged, it's probably not coming from the utility. I don't know.. do the new fancy electric meters have a remote control disconnect feature in them? I could see that being some sort of SSR. Or an automatic transfer switch or grid-tied inverter that periodically interrupts the line, to detect backfeeding from the load? Or a solar power installation with a grid-tie that's doing something weird.On your neighbor's house? With a bug that shorts the line to neutral for a millisecond, and it pulls your voltage down 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] 60 Hz line quirks, anybody recognize this stuff?
Hal, where are you taking off the signal to the audio line? At the low voltage wall wart or at the modem pin? - assuming there's an isolation or dropping resistor. I agree with others that the power company isn't doing this. There would be inductive ringing. Can you confirm with another wall wart going right to another audio channel? Or maybe a real filament transformer instead of a wart. Who knew you could find so much interesting stuff on the power line . . . Bill Hawkins P.S. I think the mild flattening of the sinusoid peaks is caused by saturation of the barely-enough-iron in the wart. -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Hal Murray Sent: Saturday, September 01, 2012 1:35 AM To: time-nuts@febo.com Subject: [time-nuts] 60 Hz line quirks, anybody recognize this stuff? The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
Perhaps a dumb question, but the wall wart is plugged into the wall, connected directly to the grid? You aren't powering the wall wart through a UPS or some type of inverter? Tom Sent from my HTC Inspire™ 4G on ATT - Reply message - From: Bill Hawkins b...@iaxs.net To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Subject: [time-nuts] 60 Hz line quirks, anybody recognize this stuff? Date: Sat, Sep 1, 2012 11:42 am Hal, where are you taking off the signal to the audio line? At the low voltage wall wart or at the modem pin? - assuming there's an isolation or dropping resistor. I agree with others that the power company isn't doing this. There would be inductive ringing. Can you confirm with another wall wart going right to another audio channel? Or maybe a real filament transformer instead of a wart. Who knew you could find so much interesting stuff on the power line . . . Bill Hawkins P.S. I think the mild flattening of the sinusoid peaks is caused by saturation of the barely-enough-iron in the wart. -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Hal Murray Sent: Saturday, September 01, 2012 1:35 AM To: time-nuts@febo.com Subject: [time-nuts] 60 Hz line quirks, anybody recognize this stuff? The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png -- These are my opinions. 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. ___ 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] 60 Hz line quirks, anybody recognize this stuff?
In the second set it looks like the wrong input is being sampled at times. Notice the offset is always the same. I have seen this happen a lot with simple sampling programs. Even if this were real I doubt it would cause false triggering of the clock. The pulse shown in the first set would. When digital clocks are run off the power line they need very good 60 Hz filtering as even a refrigerator coming on will cause trouble. David On 9/1/12 3:31 PM, tcur...@sbcglobal.net wrote: Perhaps a dumb question, but the wall wart is plugged into the wall, connected directly to the grid? You aren't powering the wall wart through a UPS or some type of inverter? Tom Sent from my HTC Inspire™ 4G on ATT - Reply message - From: Bill Hawkins b...@iaxs.net To: 'Discussion of precise time and frequency measurement' time-nuts@febo.com Subject: [time-nuts] 60 Hz line quirks, anybody recognize this stuff? Date: Sat, Sep 1, 2012 11:42 am Hal, where are you taking off the signal to the audio line? At the low voltage wall wart or at the modem pin? - assuming there's an isolation or dropping resistor. I agree with others that the power company isn't doing this. There would be inductive ringing. Can you confirm with another wall wart going right to another audio channel? Or maybe a real filament transformer instead of a wart. Who knew you could find so much interesting stuff on the power line . . . Bill Hawkins P.S. I think the mild flattening of the sinusoid peaks is caused by saturation of the barely-enough-iron in the wart. -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Hal Murray Sent: Saturday, September 01, 2012 1:35 AM To: time-nuts@febo.com Subject: [time-nuts] 60 Hz line quirks, anybody recognize this stuff? The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png ___ 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] 60 Hz line quirks, anybody recognize this stuff?
In message A25619B9FE5144D59D8C1FA34FC4D628@cyrus, Bill Hawkins writes: I agree with others that the power company isn't doing this. Not only are they not, but it also very obvious that the source is nearby, since high-frequency components suffer very high damping in the grid. My guess is an electronically switched motor, likely induction design, and most likely in your fridge or freezer, but possibly a washer or dryer. -- 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] 60 Hz line quirks, anybody recognize this stuff?
Nope. The rise/falls are far too fast for anything connected to the grid even if in the same house. If the thing is on the output of a UPS with a rapidly switched load, maybe. Any big loads, even ohmic heaters, have some inductance. I don't see any such influence. Try an oscillator. I suggested an HP 200 series because they have big output, comparable to the line. Furthermore, it's impossible for such a unit to produce an output step, if it's working right. And they are very cheap. A simple phase shift oscillator with one transistor would work also. I's not use anything digital, like a DDS. YMMV, -John == In message A25619B9FE5144D59D8C1FA34FC4D628@cyrus, Bill Hawkins writes: I agree with others that the power company isn't doing this. Not only are they not, but it also very obvious that the source is nearby, since high-frequency components suffer very high damping in the grid. My guess is an electronically switched motor, likely induction design, and most likely in your fridge or freezer, but possibly a washer or dryer. -- 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] 60 Hz line quirks, anybody recognize this stuff?
On 09/01/2012 10:57 PM, J. Forster wrote: Nope. The rise/falls are far too fast for anything connected to the grid even if in the same house. If the thing is on the output of a UPS with a rapidly switched load, maybe. Any big loads, even ohmic heaters, have some inductance. I don't see any such influence. Try an oscillator. I suggested an HP 200 series because they have big output, comparable to the line. Furthermore, it's impossible for such a unit to produce an output step, if it's working right. And they are very cheap. A simple phase shift oscillator with one transistor would work also. I's not use anything digital, like a DDS. I agree that you really need to check your measurement setup. The grid doesn't do these things, possibly something in the house, but your measurement rig is under suspicion. Professional gear for measuring power lines has filtering, so anything similar to this would be considerably smoothed out and not look like this. While professional gear has it challenges, they are beyond these issues. So, do look careful at your setup. Loose connections, intermitent connections in IC holders, stuff like that. Bad timing for the ADC. Interrupt processing, ANYTHING. 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] 60 Hz line quirks, anybody recognize this stuff?
On 09/01/2012 08:35 AM, Hal Murray wrote: The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png It's interesting to notice that you have about the same distance from the middle in all 5 examples. It's like you trigger a diode drop for a while. Notice that there is a small slope towards zero. 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] 60 Hz line quirks, anybody recognize this stuff?
On 09/01/2012 02:17 PM, Magnus Danielson wrote: On 09/01/2012 08:35 AM, Hal Murray wrote: The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png It's interesting to notice that you have about the same distance from the middle in all 5 examples. It's like you trigger a diode drop for a while. Notice that there is a small slope towards zero. 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. I have noticed many stalls in Windows lately, possibly the result of Flash and Firefox not getting along. The first plot suggests a multitasking related problem. -- Chuck Forsberg WA7KGX N2469R c...@omen.com www.omen.com Developer of Industrial ZMODEM(Tm) for Embedded Applications Omen Technology Inc The High Reliability Software 10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430 ___ 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] 60 Hz line quirks, anybody recognize this stuff?
Firefox is notorious for screwing up audio in windows. I have had OS of problems with this. I actually think its something o o with networking. Sent from my iPad On Sep 1, 2012, at 5:16 PM, Chuck Forsberg WA7KGX N2469R c...@omen.com wrote: On 09/01/2012 02:17 PM, Magnus Danielson wrote: On 09/01/2012 08:35 AM, Hal Murray wrote: The context is using the 60 Hz line for timing. I'm feeding 60 Hz from a wall wart transformer into a modem control signal that the kernel PPS stuff watches. Mostly, it works as expected, but occasionally, it picks or drops a cycle. In order to understand what was going on, I fed the same signal into the audio input and setup a job to capture the audio. Here is an example of a pick: http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a-pick.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Aug-09-a1.png OK, that somewhat makes sense. Something happened several days ago. I used to get picks/drops rarely, say ballpark of 1 a month. Now I'm getting 10 or 20 per day. So I started looking closer. I'm now seeing stuff like this. I've got lots and lots of examples. I added a second PC with different hardware. It sees the same stuff. Does anybody recognize this? http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-a0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-b0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-c0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-d0.png http://www.megapathdsl.net/~hmurray/time-nuts/line/2012-Sep-01-e0.png It's interesting to notice that you have about the same distance from the middle in all 5 examples. It's like you trigger a diode drop for a while. Notice that there is a small slope towards zero. 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. I have noticed many stalls in Windows lately, possibly the result of Flash and Firefox not getting along. The first plot suggests a multitasking related problem. -- Chuck Forsberg WA7KGX N2469R c...@omen.com www.omen.com Developer of Industrial ZMODEM(Tm) for Embedded Applications Omen Technology Inc The High Reliability Software 10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430 ___ 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.
