Re: [time-nuts] High rate, high precision/accuracy time interval counter methods

On Tuesday, May 03, 2016 02:31:17 PM Attila Kinali wrote: > Hi, > > We had here a discussion about measuring events (ie time stamping > them precisely) with high rates. As some of you know, Javier and > his group, Bruce and me are working on a system that should give > us something better than

Re: [time-nuts] High rate, high precision/accuracy time interval counter methods

I sine sampling works, but a continuous sampling allows for N samples to reduce the noise by sqrt(N) rather than 2 samples. The white-noise will be the limiting factor for the higher rates. Least-square estimation provides a 2.5 dB improvement over straight sample average. Cheers, Magnus

Re: [time-nuts] High rate, high precision/accuracy time interval counter methods

Wouldn't this be a natural application of a centroid or transition midpoint timing TDC implemented with a pulse shaper, fast ADC, and FPGA? What about sampling inphase and quadrature sine waves? This should be more amendable to a microcontroller only solution and if I had to start working on

Re: [time-nuts] High rate, high precision/accuracy time interval counter methods

Rick, Unless you uses the high-speed SERDES blocks, the jitter and systematic noises inside FGPAs can be pretty prohibitive. Enrico Rubiola and his team have made some of the best characterizations of FPGAs I've seen, but I know from several other experinces that timing can uhm shift

Re: [time-nuts] High rate, high precision/accuracy time interval counter methods

Hi Attila, On 05/03/2016 02:31 PM, Attila Kinali wrote: Hi, We had here a discussion about measuring events (ie time stamping them precisely) with high rates. As some of you know, Javier and his group, Bruce and me are working on a system that should give us something better than 10ps (my

[time-nuts] DHS S Demonstrates Precision Timing Technology at the New York Stock Exchange

Hi: A couple of weeks ago the DHS was looking into eLORAN-C for reliable timing: https://www.dhs.gov/science-and-technology/news/2016/04/20/st-demonstrates-precision-timing-technology-ny-stock-exchange -- Have Fun, Brooke Clarke http://www.PRC68.com

Re: [time-nuts] MSF 60KHz Problems?

In message <66e02a.1a25af43.445a4...@aol.com>, GandalfG8--- via time-nuts write s: >With this bypassed and a stronger signal I've also identified some varying >levels of close in interference around 60KHz, so it looks to be time for a >more detailed look at the antenna system

Re: [time-nuts] help

Since you have an impulse clock system, you could use that to fire the bell - you could modify a slave clock or use one of these : http://www.ebay.co.uk/itm/111982558390 or possibly this one : http://www.ebay.co.uk/itm/291730808914 The first seems rather expensive to me, I've more commonly

Re: [time-nuts] MSF 60KHz Problems?

Thanks to all who've commented on this. All the reports I've received have suggested that MSF is behaving normally and I've taken a closer look at my antenna system, where I've found more loss at 60KHz than expected in the multicoupler I've been using. With this bypassed and a stronger

Re: [time-nuts] help

It turns out OP (Bill Baker) is using a very nice GMR1000 GPS time standard: http://www.masterclock.com/products/master-clocks/gmr1000/ So that's why he was asking about an off-the-shelf device to turn SMPTE into an hourly switch for his fog bell. Since the GMR1000 also has a network

Re: [time-nuts] help

You don't care about the lag in cron. You care about the variation of the lag. Then again. The main cause of lag in a fog horn is the speed of sound You set cron to fire at T minus the average lag time. > On May 2, 2016, at 2:36 PM, Nick Sayer via time-nuts > wrote:

Re: [time-nuts] MSF 60KHz Problems?

Hi Nigel its been running about 17msecs fast for that last couple of months but it seemed to be corrected last week, maybe the exciter failed completely :-)) Gotta be all this snow you have been getting !! Best Wishes Alan G3NYK - Original Message - From: "GandalfG8--- via

Re: [time-nuts] help

Am 3. Mai 2016 18:06:49 MESZ, schrieb Hendrik Dietrich : > >Picking up the time from a DAYTIME Server is easier to implement than >NTP, these respond just with a string containing date and time. If you don't want to run NTP then eventually you sould use the "time" protocol

[time-nuts] help

Hi, about getting time from the Internet to a clockwork: Have a look at the ESP8266, which you can get from china for as low as 4€ in the embodiment of a AMICA board: Its a controller with some GPIOs and WLAN enabled, freely programmable (Either with the ARDUINO IDE, or with a LUA or BASIC

Re: [time-nuts] MSF 60KHz Problems?

Is anyone else seeing anthing unusual with the MSF 60KHz signal from Anthorn? For the past 24 hours or so, at least, all I've been monitoring here, approx 100 miles from Anthorn, is what seems to be a much weaker than usual carrier that's pulsing at significantly faster than once per second.

Re: [time-nuts] High rate, high precision/accuracy time interval counter methods

HP/Agilent/Keysight laser interferometers measure at the kind of rates you are talking about and (last time I heard) could divide an interference fringe down to 1/512 of a wavelength. As you say, they definitely use an ASIC with a ring oscillator. Perhaps there is some way you could repurpose

Re: [time-nuts] MSF 60KHz Problems?

Hi Nigel On 03/05/16 15:15, GandalfG8--- via time-nuts wrote: Is anyone else seeing anthing unusual with the MSF 60KHz signal from Anthorn? Can't check from here at the moment, but sounds normal from the WebSDR at UTwente... Iain ___ time-nuts

[time-nuts] High rate, high precision/accuracy time interval counter methods

Hi, We had here a discussion about measuring events (ie time stamping them precisely) with high rates. As some of you know, Javier and his group, Bruce and me are working on a system that should give us something better than 10ps (my guess is that we should get close to 1ps) at a rate of

[time-nuts] MSF 60KHz Problems?

Is anyone else seeing anthing unusual with the MSF 60KHz signal from Anthorn? For the past 24 hours or so, at least, all I've been monitoring here, approx 100 miles from Anthorn, is what seems to be a much weaker than usual carrier that's pulsing at significantly faster than once per

Re: [time-nuts] synchronization for telescopes

Hoi Michael, On Mon, 2 May 2016 07:52:09 +1000 Michael Wouters wrote: > I don't think a cheap receiver like a LEAxxx will quite get you there. I have some numbers of an project of the ETH that did use standard LEA-6T recording the phase data and got in the post

[time-nuts] help

If you want to get fancy you could modify Lady Heather to do the deed. Heather has a "singing clock" mode and a cuckoo/chime clock mode for playing sound files at various times. It also has routines for controlling the serial port DTR and RTS lines (currently used for PWMing a fan if