[time-nuts] Time interval measurement vs dual mixer

[slawek dabrowski]

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 at n1k.org>
To: Luciano Paramithiotti <timeok at timeok.it>, Discussion of precise
time and frequency measurement <time-nuts at febo.com>
Subject: Re: [time-nuts] Time interval measurement vs dual mixer
method
Message-ID: <FD4D64B6-C0F7-45D2-9EE4-E8D597814366 at 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 “within a couple of microseconds&#x201D;
as I recall.

Bob

> On Jan 17, 2018, at 1:44 AM, timeok at 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 at febo.com
>   A "time-nuts" time-nuts at 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
>