[time-nuts] Of rubidium life and piggy-bank anemia....

[Ulrich Bangert]

Paul,

you may be surprised to hear that I had read your article before and
yes, everything evolving from The Weinheim Tagung has usually a high s/n
level as has your article! After I had read about the XILINX dcms about
a year or so I had made me the same plan as you but never realized it. 

However, at that time I was in search for a TIC that would reach ns
resolution or a bit below for use in a GPSDO to measure time differences
with enough resolution so that the sawtooth error correction value of a
modern GPS receiver makes really sense to apply.

In this case I am interested in how far one can go with a modern fpga. I
have alrady made me an delay line interpolator with a ALTERA chip using
the very fast logic interconnections that the chip features for carry
transport of adders. This one reached a resolution of 110 ps but the
chip itself had many limitations. 

BTW: The way that I plan to use the dcms the jitter will be my friend
and not my enemy because I hope that I can make use of it as kind of
"dither". 

Your explanation of how the 5370 works is perfect and I wish I had read
it some years before I managed to understnd the working principle by
means of an old HP journal article written by Chu.

73 and my best regards
Ulrich, DF6JB     

> -----Ursprüngliche Nachricht-----
> Von: time-nuts-bounces at febo.com 
> [mailto:time-nuts-bounces at febo.com] Im Auftrag von Paul Boven
> Gesendet: Samstag, 1. Dezember 2007 22:55
> An: Discussion of precise time and frequency measurement
> Betreff: Re: [time-nuts] Of rubidium life and piggy-bank anemia....
> 
> 
> Hi Ulrich,
> 
> You might find the approach I used a few years a go 
> interesting, please 
> see attached paper. I hope you find the last pages 
> interesting. By the way, don't forget that DCM's cause jitter 
> themselves.
> 
> Yours sincerely, Paul Boven.
> 
> 
>