Welcome to the NavList Message Boards.


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

Compose Your Message

Add Images & Files
    Re: GPS as a time authority
    From: C Sellars
    Date: 2009 Sep 15, 13:06 -0700

    Hi John,
    I wear a Casio model 3089 that recieves a time calibration signal from
    Fort Collins ( for the US )and updates its time setting accordingly. I
    have owned this watch for 6 months and am constantly checking it
    against my Garmin 12xl gps time. I have never seen even a second
    differance. I am assuming my GPS must be doing the calculations
    necessary to give me UTC. We also use the GPS time for racing
    sailboats. This watch is amasing, I have not had to manualy set it
    since it was purchased.
    Chris Sellars
    On Sep 14, 9:05�am,  wrote:
    > I think this has been dicussed before, but I'd like to be refreshed on the list's opinion:
    > While assisting the Race Committee at a regatta this weekend, I heard the 
    timekeepers say that they were using "GPS time." �I noted that my $79 
    wristwatch, which I check monthly against the US Bureau of Standards atomic 
    clock (ph: 303-499-7111) and which doesn't lose a second per month, was 8 
    seconds ahead of the Committee's time.
    > I later checked the time shown on my hand-held Gartmin GPS receiver, and it 
    agreed with my watch. �The watch was also still in sync with the Bureau's 
    atomic clock.
    > Question: �Is the time displayed by GPS receivers considered a reliable and 
    spot-on source, up to the requirements of accurate celnav? �I would think 
    that it would be, since the GPS network depends on accurate tracking of the 
    satellites' position at a given time, yet there was that 8-second 
    discrepancy. �Perhaps the Race Committee were simply careless about setting 
    theior clockby GPS.
    > Any thoughts, List Members?
    > -John Parsons
    NavList message boards: www.fer3.com/arc
    Or post by email to: NavList@fer3.com
    To unsubscribe, email NavList-unsubscribe@fer3.com

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    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 Settings

    Posting Code:

    Custom Index

    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