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: Susceptibility of GPS to CME, Rationale for CN?
    From: Francis Upchurch
    Date: 2018 Oct 1, 04:15 +0100

    Thanks Brad. 
    The thermos is just for temperature  stability. The watches (plastic casios) 
    are wrapped in plastic insulator, the whole flask is enclosed in  a metal 
    ammo box. So should be ok I think?
    My question remains though. Does CME actually affect an unprotected quartz watch?
    Best wishes.
    -----Original Message-----
    From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Brad Morris
    Sent: 01 October 2018 02:46
    To: francis{at}pharmout.co.uk
    Subject: [NavList] Re: Susceptibility of GPS to CME, Rationale for CN?
    Hi Francis
    As Bob indicated, the watches should be in an insulator, and then enclosed
    in the metal faraday cage.
    Is the top of the thermos plastic?  Then the faraday cage isn't complete.
    Are the watches touching any metal of the thermos?  Then the insulator just
    On Sun, Sep 30, 2018, 9:29 PM Francis Upchurch 
    > Does CME affect quartz watches? I keep my 4 cheap backups in a thermos flask 
    stowed in a metal box ("Faraday cage").Should be safe?
    > I knew I might  find a practical use for my mechanical Invicta watch (cheap 
    Rolex Submariner copy)  which keeps regular time + 4-8 secs per day over the 
    last 2 years.
    > On the philosophy of time. Enjoy life and do it now. It is later than you think!
    > Francis
    > -----Original Message-----
    > From: NavList@fer3.com [mailto:NavList@fer3.com] On Behalf Of Richard B. Langley
    > Sent: 29 September 2018 13:46
    > To: francisupchurch---.com
    > Subject: [NavList] Re: Susceptibility of GPS to CME, Rationale for CN?
    > " The paucity of precise data from prior solar cycles may limit your ability 
    to predict future levels of activity."
    > It's impossible to predict when a strong solar flare or CME large enough to 
    disrupt GNSS might occur. They can even strike near the minimum of the 
    roughly 11-year solar cycle. Most outbursts are not severe enough to prevent 
    GNSS being used but simply reduce positioning accuracy with the vertical 
    coordinate (as is always the case) being a few times worse than the 
    horizontal coordinates. Potentially more impactful are strong solar radio 
    storms, which drown out the GPS signals. NOAA reported on such a storm in 
    December 2006 here: 
    (from the "Wayback Machine" as the original item is missing or got moved on 
    the NOAA site).
    > Much more impactful would be a repeat of the 1859 Carrington Event: 
    > -- Richard Langley
    > [plain text auto-generated]
    > ----------------------------------------------------------------
    > NavList message boards and member settings: http://fer3.com/NavList
    > Members may optionally receive posts by email.
    > To cancel email delivery, send a message to NoMail[at]fer3.com
    > ----------------------------------------------------------------
    > ----------------------------------------------------------------
    > View and reply to this message: 
    >  View and reply to this message
    View and reply to this message: 

    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