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Hi Markus
Ah I though I remembered seeing something ........I
think the thread was earlier this year .....Try 60Hz in the search field. They
get misty-eyed about Loran too :-))
Alan
G3NYK
----- Original Message -----
Sent: Saturday, October 04, 2014 9:17
PM
Subject: Re: LF: Re: ZEVS RX ant
question, now success - 60 Hz in Europe
Thanks Alan.
Actually the time nuts do keep an online
archive
... will look if I can find some hints
there.
73, Markus
PS Wish we could have such a nice archive
for blacksheep as well ;-)
Sent: Saturday, October 04, 2014 10:07 PM
Subject: LF: Re: ZEVS RX ant question, now success - 60 Hz in
Europe
Hi Markus there has been a lot of discussion on
the time-nuts group [email protected]
on 60Hz
frequeny accuracy across the US.. There are web sites which publish plots of
the variation. I am afraid I dont think there is an archive attachedto the
Group, though I believe it is possible to find old messages. I do have a lot
of these I will have a search though it may take some time.
Alan
G3NYK
----- Original Message -----
Sent: Saturday, October 04, 2014 8:58
PM
Subject: LF: ZEVS RX ant question, now
success - 60 Hz in Europe
Attempting to resend...
Sent: Saturday, October 04, 2014 1:18 AM
Subject: Re: LF: ZEVS RX ant question, now success - 60 Hz in
Europe
Hi Wolf, Stefan,
yes I also noticed a weak 60 Hz line during my
ELF experiment, and it is there in the accelerated wav files. Here are two
spectrograms with 15.3 mHz bin width:
Unlike Zevs, 60 Hz seems to be more
pronounced during 1855-2055 UT recording, ie our evening when the Atlantic
was still in daylight. It was hardly visible in the morning, 0541-0741
UT.
During the two evening hours, the 60 hz line
drifted up and down by about two pixels, 30 mHz. That frequency
instability may actually be a unique signature which can be used to exclude
local origin, simply by comparing simultaneous traces from two
different receive sites. I think there may even be an
online log of American line frequency history, but couldn't find
it on the web - any hints from the group?
Best 73,
Markus (DF6NM)
Sent: Saturday, October 04, 2014 12:41 AM
Subject: Re: LF: ZEVS RX ant question, now
success
Hi Stefan and all,
you wrote:
Yes, a good idea. I will try to catch it :-) But how do i know that it is
the US mains instead of a 60 Hz monitor? Is the 60 Hz from the mains more
stable?
I guess the opposite: Similar to our Eu mains frequency,
the US 60 Hz signal "wanders around" very slowly, as the load changes, but
in the long run they also keep the frequency stable, nation-wide. Not sure
about the maximum excursion from the nominal frequency (I lost the notes and
screenshots years ago when a harddisk died) and how many mHz per minute the
frequency may drift. But you can see the weak 60 Hz trace in Renato Romero's
ZEVS spectrogram at
http://www.vlf.it/zevs/zevs.htm
73,
Wolf .
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