[time-nuts] Can eloran Backup GPS?

[Bob Martin]

Courtesy a quick internet search:

http://insidegnss.com/south-korea-developing-an-eloran-network-to-protect-ships-from-cyber-attacks/

https://rntfnd.org/wp-content/uploads/Korea-Jamming-Chart.jpg

There was lots of stuff like the above.  It apparently just won't 
stay dead.

  It seems one doesn't need a cataclysm - just a bad actor like 
North Korea.

Bob Martin

On 9/9/2018 9:34 AM, paul swed wrote:
> The correction stream is transmitted in the eLORAN signal and does require
> some form of reference site to transmitter connection. Just like GPS and
> lightspeed use RF to send corrections to the satellites.
> Loran C also did the same adjustments from a control site.
> But I am hearing nothing about eLORAN these days. It does not show up very
> often anymore in some of the navigation publications.
> Regards
> Paul
> WB8TSL
> 
> On Sun, Sep 9, 2018 at 11:20 AM, Poul-Henning Kamp <phk at phk.freebsd.dk>
> wrote:
> 
>> --------
>> In message <3d2ae1be-927a-574a-e7f0-c7d2d289dc39 at earthlink.net>, jimlux
>> writes:
>>> On 9/8/18 4:52 PM, paul swed wrote:
>>
>>> I suppose you could have a low rate network (i.e. not "the internet")
>>> and for the most part, the propagation corrections (whether using 60kHz,
>>> Loran, Omega, or GPS) can be done with "climatology" - time of day and
>>> time of year.
>>
>> Transmitting real-time corrections is not the problem, coming up
>> with them in the first place is.
>>
>> One of the reasons eLoran failed to go anywhere in europe is that
>> tests showed that modern container freighters are big enough to
>> 'relevantly disturb Loran-C'.
>>
>> Nobody has a clue how you could possibly measure the necessary
>> real-time corrections for narrow and heavily trafficked straits
>> like as The English Channel, The Great Belt etc.
>>
>> For big/expensive boats, INS/IMU is the goto-solution, at around
>> $20-50k a piece, depending on specs.
>>
>> In difference from anything relying on radio signals from people
>> you can maybe trust some of the time, INS/IMU is entirely on-board,
>> which can lower your insurance premiums if you sail certain parts
>> of the world.
>>
>> --
>> Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
>> phk at FreeBSD.ORG         | TCP/IP since RFC 956
>> FreeBSD committer       | BSD since 4.3-tahoe
>> Never attribute to malice what can adequately be explained by incompetence.
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts at lists.febo.com
>> To unsubscribe, go to http://lists.febo.com/mailman/
>> listinfo/time-nuts_lists.febo.com
>> and follow the instructions there.
>>
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>