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: Differences between GPS and WWV time
    From: UNK
    Date: 2001 Jun 22, 1:26 PM

    Robert Owens [mailto:tugly{at}NEOSOFT.COM] asked:
    > Has anyone noticed a difference between GPS and WWV time. I hear some
    units
    > display a different time  depending on software.
    
    The GPS system broadcasts time as a week number (where Week 0 began
    at 00:00:00 6 Jan 1980 UTC) and seconds-of-week. Somewhere else in the
    broadcast message is the current difference between this strict
    sequential count and UTC, since UTC has had a dozen or so leap seconds
    inserted since the beginning of the GPS epoch. All but the most
    primitive receivers correctly apply the leap second correction.
    However, as Dan Allen noted, receivers' internal clocks often drift,
    and shouldn't be trusted until the unit is tracking.
    
    An interesting variation on the "Y2K Bug" of recent memory was GPS week
    roll-over. The week field is 10 bits long, so in August 1999 it rolled
    over from week 1023 to week 0. Some early GPS receivers needed software
    updates or some other intervention in order to cope.
    
     -- Peter
    

       
    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