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 <[email protected]> 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" <[email protected]> To: <[email protected]> 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 -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
