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    Re: A One-Hour Presentation on Celestial Navigation
    From: Francis Upchurch
    Date: 2016 Mar 19, 06:17 -0000

    Re. Radio time signals.(Sorry, is this a new topic?)

    Bob and Frank,

    I was interested in the question of how early were radio time signals available to make an ordinary watch useful as a chronometer?

    The Royal Navy had time signals by 1910 , I think. The BBC time “pips” started in 1924 as did the BBC world service, so I assume this would have given potentially world-wide coverage? (https://en.wikipedia.org/wiki/Greenwich_Time_Signal) Ironically, they are no longer accurate due to time lags of “modern” digital radio!

    Harry Pigeon, a not particularly well healed sailor, apparently had 2 second hand watches in 1922 for his single handed circumnavigation. He did not use time signals then and even risked his life rowing out through dangerous surf one night in the Pacific Islands to wind up his watches and as he says” save his longitude”. This of course was not necessary, since he knew the exact longitude of his anchorage and should have known how to find GMT by working backwards from that.

    Cheap homemade crystal radios were common by the mid 1920s (https://en.wikipedia.org/wiki/Crystal_radio).

    PS. I am glad you have finally put the Slocum lunar and tin clock myth to bed! I get the impression he surprised himself with the apparent success of his one and only lunar. He set off happily on his circumnavigation, confident of managing with just latitude sailing and very accurate (actually, amazing) DR. He must have known this, since the cost of repairing his “good” chronometer was $15, compared to the thousand spent on his rebuild of “Spray”. Also,  I find it hard to believe a retired sea captain would not have had a good pocket watch?  His famous, (or infamous!) single lunar gave him a longitude within 5  miles of his DR after months sailing across the Pacific. That DR skill was his greatest navigation achievement for me, not his lunar. I’ve seen similar DR skills in old fisherman here in Cornwall, who in pre-GPS days just knew where they were.

    Best wishes




    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Bob Goethe
    Sent: 19 March 2016 00:29
    To: francisupchurch@gmail.com
    Subject: [NavList] Re: A One-Hour Presentation on Celestial Navigation


    >>I would note that time-keeping at sea in the latter half of the twentieth century did not necessarily depend on a quality chronometer. It depended on good shortwave reception!<<

    Right you are! 

    Now, I left that out of my presentation, since I don't have any idea about when SW radios became practical for small boat sailors.  I presume that tube-radios never really made it big in small boats.  I think Sony brought out the first transistor radio in 1954.  I don't know when usable, affordable marine radios came onto the market.

    The other thing to note is when shortwave radio time signals became ubiquitous.  According to Wikipedia...

    WWV had been broadcasting second pulses since 1937, but these pulses were not tied to actual time. In June 1944, the United States Naval Observatory allowed WWV to use the USNO's clock as a source for its time signals. Over a year later, in October 1945, WWV broadcast Morse code time announcements every five minutes. Voice announcements started on January 1, 1950, and were broadcast every five minutes....

    WWV moved to its present location near Fort Collins on December 1, 1966, enabling better reception of its signal throughout the continental United States.

    So I expect there was a transition to "good times" on small boats, which related to the availability of time signals, affordable (and ruggedized) marine equipment that could pick up those signals, and cheap but accurate wristwatches.  This probably was not there for the small boat sailor in 1930, likely was not there either in 1940.  By 1950, in their newly minted fiberglass sloops, some sailors were getting good time, maybe.  By 1960, probably.  And by 1970, certainly.

    I realize now that the shortwave radio I got in 1968, while I was in high school, was picking up signals here in Alberta that were probably not there at all just a couple of years before, prior to WWV moving to Colorado.  I used to delight in setting my cheap Timex watch to the CORRECT time.  Now I have a radio controlled Casio.  So in some respects, I have not changed much over the past 45 or 50 years.

    I noticed a little while ago how much our assumptions about time have shifted over the decades.  In 1970, you could be 10 minutes late (or early) and that was just normal.  Nobody thought anything of it, since most watches gained or lost several minutes a day.  Recently, I was going to pick somebody up for a church board meeting, and I was 2 minutes late.  The person assumed I had completely forgotten her, and started to walk.  Wow!  Nobody would ever have done that in 1970.  It simply would not have occurred to anybody to expect that degree of punctuality.


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