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Discussion of precise time and frequency measurement

Re: [time-nuts] Time interval measurement vs dual mixer

slawek dabrowski

Thu, Jan 18, 2018 8:46 PM

Hi,

Thanks for all answers. I'm trying to estimate the uncertainty of GPS Common View data (which is based on TIE measurement) and compare it to data from dual mixer method.

Message: 6
Date: Wed, 17 Jan 2018 11:08:45 -0500
From: Bob kb8tq kb8tq@n1k.org
To: Luciano Paramithiotti timeok@timeok.it, Discussion of precise
time and frequency measurement time-nuts@febo.com
Subject: Re: [time-nuts] Time interval measurement vs dual mixer
method
Message-ID: FD4D64B6-C0F7-45D2-9EE4-E8D597814366@n1k.org
Content-Type: text/plain; charset=utf-8

If the time offset gets to the point that it bothers the measurement, you likely are
running to low a difference frequency. It is quite possible (though not easy) to get
low parts in 10^-13 running an offset of 8 or 9 Hz at 10 MHz.

If you are running very precise signals, then line stretchers can be used to get
everything so it hits at the same point. There are NBS papers where they talk
about doing exactly this sort of thing. Results were âświthin a couple of microseconds”
as I recall.

Bob

On Jan 17, 2018, at 1:44 AM, timeok@timeok.it wrote:

Hi Slawek,
I have tried two versions of DMTD and I think the biggest problem with this method is the fact that two measures made on the same DUT never coincide.
The DMTD suffers from time wrap and the measurement results are linked to the time difference presetted by t1 and t2.
At the moment I am using the TICC with good results, attached to the noise floor.
I think that in order to have a better resolution we need to focus on a recent production
error multiplier such as the A7 of Quartzlock or a similar one to be self-constructing.
http://quartzlock.com/userfiles/downloads/manuals/A7-A_&_A7-MX_Manual.pdf
Luciano
www.timeok.it

Da "time-nuts" time-nuts-bounces@febo.com
A "time-nuts" time-nuts@febo.com
Cc
Data Tue, 16 Jan 2018 17:58:18 +0100
Oggetto [time-nuts] Time interval measurement vs dual mixer method

Hello to the group!

Have you ever measured frequency standard (or other precision oscillator) simultanously by time interval method (difference between 1 pps ref and 1 pps DUT) and dual mixer method (e.q. with phase/frequency comparator)? I'm very interested in results.

Slawek

Hi, Thanks for all answers. I'm trying to estimate the uncertainty of GPS Common View data (which is based on TIE measurement) and compare it to data from dual mixer method. Message: 6 Date: Wed, 17 Jan 2018 11:08:45 -0500 From: Bob kb8tq <kb8tq@n1k.org> To: Luciano Paramithiotti <timeok@timeok.it>, Discussion of precise time and frequency measurement <time-nuts@febo.com> Subject: Re: [time-nuts] Time interval measurement vs dual mixer method Message-ID: <FD4D64B6-C0F7-45D2-9EE4-E8D597814366@n1k.org> Content-Type: text/plain; charset=utf-8 Hi If the time offset gets to the point that it bothers the measurement, you likely are running to low a difference frequency. It is quite possible (though not easy) to get low parts in 10^-13 running an offset of 8 or 9 Hz at 10 MHz. If you are running very precise signals, then line stretchers can be used to get everything so it hits at the same point. There are NBS papers where they talk about doing exactly this sort of thing. Results were âświthin a couple of microseconds” as I recall. Bob > On Jan 17, 2018, at 1:44 AM, timeok@timeok.it wrote: > > > Hi Slawek, > I have tried two versions of DMTD and I think the biggest problem with this method is the fact that two measures made on the same DUT never coincide. > The DMTD suffers from time wrap and the measurement results are linked to the time difference presetted by t1 and t2. > At the moment I am using the TICC with good results, attached to the noise floor. > I think that in order to have a better resolution we need to focus on a recent production > error multiplier such as the A7 of Quartzlock or a similar one to be self-constructing. > http://quartzlock.com/userfiles/downloads/manuals/A7-A_&_A7-MX_Manual.pdf > Luciano > www.timeok.it > > > Da "time-nuts" time-nuts-bounces@febo.com > A "time-nuts" time-nuts@febo.com > Cc > Data Tue, 16 Jan 2018 17:58:18 +0100 > Oggetto [time-nuts] Time interval measurement vs dual mixer method > > Hello to the group! > > Have you ever measured frequency standard (or other precision oscillator) simultanously by time interval method (difference between 1 pps ref and 1 pps DUT) and dual mixer method (e.q. with phase/frequency comparator)? I'm very interested in results. > > Slawek >