[time-nuts] 1937 Time Standard

Dave Brown tractorb at ihug.co.nz
Tue May 24 02:10:21 EDT 2016


In the context of public time dissémination, the Shepherd master and gate 
clocks are worth noting as well-
http://collections.rmg.co.uk/collections/objects/79636.html
 But somewhat earlier than 1937......
 DaveB, NZ

----- Original Message ----- 
From: "Tom Van Baak" <tvb at LeapSecond.com>
To: "Discussion of precise time and frequency measurement" 
<time-nuts at febo.com>
Sent: Tuesday, May 24, 2016 12:57 PM
Subject: Re: [time-nuts] 1937 Time Standard


> Thanks Paul.
>
> I accumulate a pile of PDF's over time and when the right question shows 
> up in the list I dig them out. It turns out Thomas, the OP, is doing a 
> report on public clocks, including synchronous motor clocks. He added 
> another source:
> https://clockhistory.com/telechron/company/documents/warren_1937/index.html
>
> The idea of time standards and time transfer methods has not changed over 
> the centuries. What these guys did way back with telegraph (Western Union) 
> or with 60 Hz (Telechron) we now do with WWVB, NTP, GPS, etc. The decimal 
> point moves.
>
> The history of 60 Hz mains frequency, in particular, is extremely 
> fascinating.
> There's some basic intro here: 
> https://en.wikipedia.org/wiki/Utility_frequency#History
> Have a look at that table of frequencies used in 1897!
>
> There's a great article (free, IEEE) on the use of 25 Hz at Niagara Falls:
> http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=4412948
>
> And some wonderful information here:
> http://ethw.org/Early_Electrification_of_Buffalo
>
> Finally, this 3 part masterpiece:
> http://ethw.org/Archives:Transformers_at_Pittsfield,_part_1
> http://ethw.org/Archives:Transformers_at_Pittsfield,_part_2
> http://ethw.org/Archives:Transformers_at_Pittsfield,_part_3
>
> If nothing else, everyone should take a quick look at the photos in the 
> above 3 URL's. Mini-Circuit transformers these are not.
>
> /tvb
>  ----- Original Message ----- 
>  From: paul swed
>  To: Tom Van Baak ; Discussion of precise time and frequency measurement
>  Sent: Monday, May 23, 2016 4:23 PM
>  Subject: Re: [time-nuts] 1937 Time Standard
>
>
>  Some good articles I have read several that you sent Tom. Its funny such 
> great information if you just search on the right terms.
>  But then I appreciate the fact that you sent great links. No guessing.
>  More to go and read.
>  Regards
>  Paul
>  WB8TSL
>
>
>  On Sat, May 21, 2016 at 4:50 PM, Tom Van Baak <tvb at leapsecond.com> wrote:
>
>    Hi Thomas,
>
>    > I was wondering if anyone knew what the "state of the art" time 
> standard was in the 1937 ?
>
>    The 1930's were an exciting time in this regard.
>
>    The best time standards (in vacuum pendulum clocks) were those used by 
> astronomers. Google: Shortt-Synchronome.
>
>    Laboratory quartz clocks had just been developed. During this decade 
> the best pendulum clocks were compared to the best quartz clocks. Google: 
> Marrison Loomis Shortt
>
>    And in the race between these two technologies, it was shown in 1936 by 
> Scheibe and Adelsberger that irregularities seen by astronomers were due 
> to the earth itself and not the pendulum or quartz clocks. This eventually 
> led to the leap second. It was common to use a set of 3 clocks to do the 
> comparison (sound familiar)
>
>    To get a sense of the world of precise time in the 1930's I would 
> recommend reading the following, each of which mentions something about 
> the past century of timekeeping.
>
>    The Evolution of the Quartz Crystal Clock
>    http://www.ieee-uffc.org/main/history-marrison.asp
>    https://ia902701.us.archive.org/25/items/bstj27-3-510/bstj27-3-510.pdf
>
>    Time – the SI Base Unit “Second”, by Andreas Bauch
> 
> https://www.ptb.de/cms/fileadmin/internet/fachabteilungen/abteilung_4/4.4_zeit_und_frequenz/pdf/2012_Bauch_PTBM_125a_en.pdf
>
>    The Evolution of Time Measurement, Part 2: Quartz Clocks
>    http://tf.boulder.nist.gov/general/pdf/2533.pdf
>
>    Atomichron: The Atomic Clock from Concept to Commercial Product
>    http://www.ieee-uffc.org/main/history-atomichron.asp
>
>    Precision time and the rotation of the Earth, by Dennis McCarthy
> 
> http://journals.cambridge.org/download.php?file=%2FIAU%2FIAU2004_IAUC196%2FS1743921305001377a.pdf
>
>    Some Aspects of Precision Time Measurement -- 1930's German quartz, 
> Lothar Rohde, etc.
>    http://pubs-newcomen.com/tfiles/75ap119.pdf
>    http://www.cdvandt.org/PTR%20quartz-clock.pdf
>    http://www.cdvandt.org/CFQ.pdf
>    http://www.cdvandt.org/BIOS-1316.pdf
>
>    I have more links and PDF's to share. But let's first find out how deep 
> an answer you actually want.
>
>    Thanks,
>    /tvb
>
>
>    ----- Original Message -----
>    From: "Thomas D. Erb" <tde at electrictime.com>
>    To: <time-nuts at febo.com>
>    Sent: Saturday, May 21, 2016 11:40 AM
>    Subject: [time-nuts] 1937 Time Standard
>
>
>    >I was wondering if anyone knew what the "state of the art" time 
> standard was in the 1937 ?
>    >
>    >
>    >
>    >
>    >
>    >
>    > _______________________________________________
>    > time-nuts mailing list -- time-nuts at febo.com
>    > To unsubscribe, go to 
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>    > and follow the instructions there.
>    _______________________________________________
>    time-nuts mailing list -- time-nuts at febo.com
>    To unsubscribe, go to 
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>    and follow the instructions there.
>
>
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to 
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there. 



More information about the time-nuts mailing list