Re: [time-nuts] Roughtime

2016-10-04 Thread Ruslan Nabioullin
On 10/05/2016 01:17 AM, Chris Albertson wrote: All that said, there is money to be made by spoofing time. If I can fool a stock broker into accepting trades minutes late I could be rich. Minutes? I thought the proper unit for that is nanoseconds :). -Ruslan

Re: [time-nuts] Roughtime

2016-10-04 Thread Chris Albertson
The current system is very secure. The paper is correct in the most users don't bother with authentication or encryption. I don't.But let's say some one tried to spoof me into thinking it is three seconds later then it really is by some how setting up an NTP server that gives me incorrect

Re: [time-nuts] Need Time Help

2016-10-04 Thread Chris Albertson
On Tue, Oct 4, 2016 at 6:52 PM, Bob Camp wrote: > Hi > > If: > > 1) You are a typical Ham in a home environment > 2) All the servers are “out there” on the internet > 3) You have any of the normal modems feeding your home > > You have a very basic issue in terms of path delay. All

[time-nuts] Roughtime

2016-10-04 Thread Christopher Hoover
I just learned about this from a public post: https://roughtime.googlesource.com/roughtime/ Not precise enough for us nuts, but intended to be secure. (I wonder how it handles leap seconds? Too soon? :-) Actually, it smears.) -christopher. de AI6KG

Re: [time-nuts] Need Time Help

2016-10-04 Thread Paul
On Tue, Oct 4, 2016 at 9:05 PM, Chris Albertson wrote: > The problem, I think with your Internet sync's NTP servers is you are only > using one server S. The most common practice is to use 3 to 5 with 5 being > about the right number. If you get Ntp enough Internet

Re: [time-nuts] Need Time Help

2016-10-04 Thread Bob Camp
Hi If: 1) You are a typical Ham in a home environment 2) All the servers are “out there” on the internet 3) You have any of the normal modems feeding your home You have a very basic issue in terms of path delay. All the servers you can access have the *same* asymmetric delay. In that case, no

Re: [time-nuts] Need Time Help

2016-10-04 Thread Chris Albertson
The problem, I think with your Internet sync's NTP servers is you are only using one server S. The most common practice is to use 3 to 5 with 5 being about the right number. If you get Ntp enough Internet servers to work with it can detect problem like asymmetric path lengths which I'm sure is

Re: [time-nuts] Need Time Help

2016-10-04 Thread Attila Kinali
On Tue, 4 Oct 2016 15:41:58 +1100 Larry Hower wrote: > Ultimately we want sub-millisecond accuracy. If you want to go that way, you will have to leave windows as this operating system does not offer the facilities to get down to such a low levelUnless you calibrate the

Re: [time-nuts] AC line distortion [Was: HP 105B Battery, the saga continues]

2016-10-04 Thread Jeremy Nichols
Thank you all for the inputs. In the present case, the location is my home about an hour north of San Francisco, California. We are in a rural location with other homes and some small businesses (legal or otherwise). There could be many things hung on the 60 Hz power lines adding noise to the

[time-nuts] Need Time Help

2016-10-04 Thread Mark Sims
Lady Heather has support for setting the system clock from the GPS receiver. The next release has support for analyzing and compensating for the GPS / system / com port message delay. It does not use the 1PPS signal. It can get the Windoze clock to under 40 msecs (two times the typical

Re: [time-nuts] Need Time Help

2016-10-04 Thread Chris Albertson
I think to sum up what has been written 1) USB connection will not work well for timing 2) Notebook computers dont work well for timing 3) A good NTP server on your LAN can get you "close" to what you need even on PC notebooks 4) With effort and a real serial port and after downloading a copy of

Re: [time-nuts] Need Time Help

2016-10-04 Thread Pete Stephenson
On 10/4/2016 6:41 AM, Larry Hower wrote: > Hello to the List: Hi and welcome! > After a long and bitter struggle with XP and WIN 10, I am writing to ask > for some help in solving some problems we have been having in our attempt > to establish a very accurate time reference for use in EME

Re: [time-nuts] Need Time Help

2016-10-04 Thread Rob Kimberley
Suggest you try the following which I use on Win10 with great success https://www.meinbergglobal.com/english/sw/ntp.htm#ntp_stable and https://www.meinbergglobal.com/english/sw/ntp-server-monitor.htm Rob K -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On

Re: [time-nuts] Need Time Help

2016-10-04 Thread Tom Van Baak
Hi Larry, You are using a bunch of h/w and s/w together and you want each piece to maintain precise time. Would it be possible for you to inject a very short GPS 1PPS pulse or GHz tone into your antenna feed? That will cause a slight blip in your raw data which your processing s/w can then

Re: [time-nuts] Need Time Help

2016-10-04 Thread jimlux
On 10/4/16 6:26 AM, Graham / KE9H wrote: Larry: You have multiple problems, with the way you are trying to define "time-error." I think you are defining it as the time error of the signal coming out of your receivers/decoders. You are blending all the error/delay sources together, and you

Re: [time-nuts] Need Time Help

2016-10-04 Thread dl3hc
Hello Larry, for Windows i know only one piece of software that is able to set the system clock within a few milliseconds. Dimension4. http://www.thinkman.com/dimension4/features.htm Since I have not yet even measured it i can not tell if it meets your specifications. Maybe you give it a

Re: [time-nuts] Need Time Help

2016-10-04 Thread David J Taylor
From: Graham / KE9H Larry: [] First, the reflector has already jumped in and helped you with the definition of absolute time. You can get single digit millisecond accuracy (with some caviats and bewares) from NTP, for stations at different locations. You should be able to get single digit

Re: [time-nuts] AC line distortion [Was: HP 105B Battery, the saga continues]

2016-10-04 Thread Scott Stobbe
Considering some signal generators will have 1% (-40dBc) distortion with a 5k - 10k price tag, your 1% is not to bad. On Mon, Oct 3, 2016 at 8:52 PM, Jeremy Nichols wrote: > As an experiment, I bought an AIMS sine-wave inverter for the 105B Quartz > Oscillator. The inverter

Re: [time-nuts] Need Time Help

2016-10-04 Thread Graham / KE9H
Larry: You have multiple problems, with the way you are trying to define "time-error." I think you are defining it as the time error of the signal coming out of your receivers/decoders. You are blending all the error/delay sources together, and you need to break them apart, since each one will

Re: [time-nuts] Need Time Help

2016-10-04 Thread Bob Camp
Hi As others have mentioned, you have two strikes against you: 1) Modern laptops *love* power saving. That makes them poor time keepers at the millisecond level. It takes some well thought out software in the OS to keep track of all the strange things they do. 2) Windows XP is getting a bit

Re: [time-nuts] AC line distortion [Was: HP 105B Battery, the saga continues]

2016-10-04 Thread Bob Camp
Hi A lot of the distortion on the AC line is locally produced. Consider a very normal bridge rectifier running into a capacitor. It draws “all” the current in narrow spikes near the peaks of the sine wave. A half wave rectifier would be even worse (only one spike per cycle). That highly

Re: [time-nuts] AC line distortion

2016-10-04 Thread Adrian Rus
Maybe living on other "countries" ? :) When you live at the end of the power line, at many km from the last low voltage transformator and when the lines are over-loaded, their distributed inductance + their distributed capacitance [?] make the voltage hump to "sleep". It's rising front is

Re: [time-nuts] AC line distortion

2016-10-04 Thread Thomas D. Erb
Maybe a capacitive load in your facility ? Whenever I've looked at it - it's always been pretty clean. For years we used the AC mains for time keeping - but have found in some locations - especially ones with lots of dimmers - zero crossing counting was ineffective. My feeling was that dimmers

Re: [time-nuts] Need Time Help

2016-10-04 Thread Clint Jay
What's being transmitted? If it's a repetitive message would it be possible to inhibit transmission using an external time source, perhaps a PIC or even a Pi inhibiting the "PTT", leaving the windows box in control of what's transmitted or do the Windows boxes have to communicate with each other

Re: [time-nuts] AC line distortion

2016-10-04 Thread Charles Steinmetz
Jeremy wrote: The result was about 5% distortion for the inverter and 1.5% for the AC line. This got me to wondering, we've discussed the AC power line frequency at length but not other "qualities" of that "signal.' I was surprised that the AC line had so much distortion but it's a subject I've

Re: [time-nuts] Need Time Help

2016-10-04 Thread David J Taylor
From: Hal Murray david-tay...@blueyonder.co.uk said: You can use a GPS puck or equivalent with PPS output to get the sort of accuracy you need. ..: PPS output is only half the battle. You also have to get it into the system that needs it. A modem control signal on an old fashioned serial

Re: [time-nuts] Need Time Help

2016-10-04 Thread Martin Burnicki
You can find some information here : https://www.meinberg.de/download/burnicki/time_synchronization_accuracy_with_ntp.pdf Please note the resolution of the system time in Win XP is only about 16 ms. The NTP service tries to extrapolate the system time to yield better resolution, but applications

Re: [time-nuts] Need Time Help

2016-10-04 Thread Hal Murray
david-tay...@blueyonder.co.uk said: > You can use a GPS puck or equivalent with PPS output to get the sort of > accuracy you need. ..: PPS output is only half the battle. You also have to get it into the system that needs it. A modem control signal on an old fashioned serial port (not USB)

Re: [time-nuts] Need Time Help

2016-10-04 Thread Chris Albertson
On Mon, Oct 3, 2016 at 9:41 PM, Larry Hower wrote: > > > 1. We are using desktops and laptops in separate locations running XP or > Win 10. > Assuming you have decent GPS receivers with an un-obstructed view of the sky with 1 pulse per second output and you have let the GPS run

Re: [time-nuts] Need Time Help

2016-10-04 Thread David J Taylor
Hello to the List: After a long and bitter struggle with XP and WIN 10, I am writing to ask for some help in solving some problems we have been having in our attempt to establish a very accurate time reference for use in EME activities. We are hoping to achieve less than 5ms deviation, although

Re: [time-nuts] AC line distortion [Was: HP 105B Battery, the saga continues]

2016-10-04 Thread Adrian Rus
Yes, I did intensive measurements of power line quality. If the voltage THD of your AC line is only 1.5%, then your area is supplied by vry good quality energy. Mine exceeds 10% :(. Not only the THD as number is important, for certain applications the shape is important, too [how you got

[time-nuts] AC line distortion [Was: HP 105B Battery, the saga continues]

2016-10-04 Thread Jeremy Nichols
As an experiment, I bought an AIMS sine-wave inverter for the 105B Quartz Oscillator. The inverter has a built-in transfer switch that is supposed to allow the load to operate from the AC line and automatically switch to battery/inverter should the AC power line fail. In fact the thing seems