[time-nuts] Clock Powers of Ten

Alan Melia alan.melia at btinternet.com
Thu Jan 31 19:51:32 EST 2008

Hi, I dont know about other counties but the oad shedding is certainly still
dont this way in the UK, BUT the incremental frequency adjectments are
corrected for the mean daily frequency to be correvt at 06:00 in the
morning.... so that all the clocks read correctly and we get to work on
time!! Despite quartzz clocks I think this is still the case....it is
probably enshrined in law in the UK. Also Our nominal voltage is 240v not
the 230v decreed by the EU fortunately we can still be fed 240v within the
tolarance allows otherwise my toaster would take forever. There is actually
a considerable difference in the light output of a tungsten bulb over that
range maybe that is why we are being forced into using "polluting"
CFBs...nutting to do with time ...sorry pardon
Great site Tom !!
Alan G3NYK

----- Original Message -----
From: "Sylvain RICHARD" <sr75pro at free.fr>
To: "Discussion of precise time and frequency measurement"
<time-nuts at febo.com>
Sent: Friday, February 01, 2008 12:25 AM
Subject: Re: [time-nuts] Clock Powers of Ten

   michael taylor a écrit :

On Jan 31, 2008 5:27 PM, Sylvain RICHARD [1]<sr75pro at free.fr> wrote:

Re the mains frequency, I believe it changes with the load on the grid.
Do you have a record of this?

I forget the reasoning for frequency variation, but it is load or
source related I believe. Part of the reason it

   It is a balance between production and grid load. In the European case,
   the grids are phase synchronous over several countries. The (oldish)
   data I have is
   - Nordel : Finland, Norway, Sweden, Denmark
   - Uktsoa :  UK.
   - Atsoi : Irland
   - Ucte : everybody else in Western Europe : Portugal, Spain, France,
   Netherlands, Belgium, Luxembourg, Germany, Switzerland, Austria, Italy,
   Czech Republic, Slovakia, Poland, Hungary, Romania, ex-Yougoslavia
   During the 2006 blackout, the frequency went down by several hertz
   before some customers were disconnected ("load shedding"). The so
   familiar 50Hz line on VLF spectrograms took a dip.

A project for a easy to build AC frequency measuring device:

I could log the frequency deviations from my local AC mains if you
want some sample data.

   This gadget looks nice, but I think I'll pass.
   Good night


   1. mailto:sr75pro at free.fr
   2. http://www.sparetimegizmos.com/Hardware/AC_Monitor.htm
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to
and follow the instructions there.

More information about the time-nuts mailing list