Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    or...
       
    Reply
    Re: Chronometer Suggestions
    From: Paul Hirose
    Date: 2009 Jan 11, 09:18 -0800

    It may be interesting to look at the seasonal variations in daily rate
    of an ordinary battery powered wall clock. I check this clock monthly,
    so the values are the average daily rate for the month. All values are
    positive, i.e., the clock always runs fast.
    
          2006  2007  2008
    Jan   .40   .38*  .37
    Feb   .40   .45   .39
    Mar   .38   .46   .44
    Apr   .43   .46   .45
    May   .47   .50   .50
    Jun   .48   .52   .52*
    Jul   .40   .48   .50
    Aug   .48   .48   .49
    Sep   .47   .50   .52
    Oct   .44   .47   .49
    Nov   .41   .41   .46
    Dec   .35   .38   .41
    
    * new battery installed at beginning of this month
    
    
    And here are values for a $25 Timex digital watch I bought in 2000. It
    still has the original battery. I don't wear this watch a lot; probably
    less than 5 hours per week.
    
          2006  2007  2008
    Jan   .43   .41   .42
    Feb   .40   .42   .42
    Mar   .41   .43   .45
    Apr   .41   .41   .43
    May   .39   .41   .42
    Jun   .34   .40   .38
    Jul   .26   .35   .34
    Aug   .35   .34   .34
    Sep   .40   .40   .40
    Oct   .43   .45   .43
    Nov   .43   .44   .46
    Dec   .41   .43   .44
    
    
    The time checks are by eye and ear using WWV on a cell phone. By
    comparing the phone audio to the audio from a shortwave receiver I've
    found that the phone is consistently 1/4 second late, as well as I can
    estimate, so this constant is disregarded.
    
    My monthly error checks are accurate to perhaps 1/4 second, so the
    corresponding daily rate is probably accurate to plus or minus .01 second.
    
    --
    I block messages that contain attachments or HTML.
    
    
    --~--~---------~--~----~------------~-------~--~----~
    Navigation List archive: www.fer3.com/arc
    To post, email NavList@fer3.com
    To unsubscribe, email NavList-unsubscribe@fer3.com
    -~----------~----~----~----~------~----~------~--~---
    
    

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.
    Email:

    Email Settings

    Posting Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site