My ECDIS and radar are side by side. I can plot on the ECDIS before you can even walk to the chart.
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Oh yeah? 
Yeah.
I’m on my way with a ship right now -
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He was onboard when it happened
Press said it was the second blackout the vessel had
Suspect that the vessel will surge with faulty tension input to dp
L2 L5 got nothing to do with spoofing
L2 is a signal on different frequency so via doppler shift you can work out how the signal was bent in the atmosphere.
For whatever reason it is encoded but all 3rd party vendors decode and use it
L5 signal not coded so civilian receivers can use it as you say so it bit more accuracy to your phone.
Its not public info how the military know when they are spoofed but it was obvious from the get go it could happen so they must of had a method to get around it.
The GNSS industry suspect they get a almanac from a secure source and keep comparing that to what the sats are sending them.
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So is L5.
I would need way more than you saying “dude trust me” as a source for this. I highly doubt the military allows civilian sources to decode their L2 signal, though as I said, there’s now an uncoded L2C (civilian) broadcast available that’s separate from the encoded military L2 channel. (That means that just because your DP correction paid provider may use an L2 channel doesn’t mean they’re using the encoded military channel.)
I’m pretty sure that’s the primary reason the military first developed their L2 channel so I’m not sure why you think it’s “got nothing to do with spoofing”.
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every vendors receivers have had that feature for decades..
Anyone with a DP ticket should know that
Trimble, C-nav Fugro etc
a cut and paste from Fugro features of various receivers:
Trust but verify….
Seastar® XP3
Accuracy phase based service, using orbit/ clock data valid worldwide, based on GPS, GLONASS and Galileo L1 and L2 frequencies. Independent of G2/G4.
Seastar® XP2
Accuracy phase based service, using orbit/ clock data valid worldwide, based on GPS and GLONASS L1 and L2 frequencies. Independent of G2/G4.
Seastar® XP
Accuracy phase based service, using orbit/ clock data valid worldwide, based on GPS L1 and L2 frequencies. Independent of G2/G4.
Seastar® SGG
Integrated DGPS/DGLONASS, sub metre level, code based service using orbit/clock data based on GPS, GLONASS, Galileo and BeiDou L1 and L2 frequencies.
L2C has been broadcast by every Navstar satellite launched since 2005…
Do you have any evidence that these vendors are decrypting the encoded military L2 channel like you claimed instead of using the civilian L2C?
The decryption is not complex as explained to me by a receiver vendor and then later discovered its the same signal as L2C
There are no secret signals coming out of navstar sats certainly nothing for accuracy.
The big issues to deal with is the atmosphere interference and non symmetrical orbits which change the time and distance
It’s true that many ship’s officer of my age cohort don’t want to learn new skills so it’s become a stereotype.
The problem isn’t that the technology has shortcomings That’s covered in the classes. it’s that the human brain is vastly better at building situational awareness from direct visual reality than from abstract screen symbols.
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Being of an age when ARPA and ECDIS among other things were thrown on ships before the legislation caught up the manuals were all we had. The Filipino electrician and I installed the AIS at sea.
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Does the IMO know there are computers on board yet?
ECDIS mess and the rule that allows you to turn it off ( assuming paper bridge is possible) says it all.
One faulty wire blacks out a ship and brings a bridge down says same issue in engine room.
Is the industry just lucky or should it go back to coal and sextant where it sounds like it belongs.
Class is there to make rules after enough deaths or expensive destruction brings it to the public’s attention.
Aircraft are getting better but trainees getting worse hence the crashes.
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I hate plotting LOPs on the ECDIS because our JRC will automatically close any window after about five seconds without any mouse input. If you’ve plotted a line or two and it auto-closes before you finish your last one, it saves nothing. Dialing in your range or bearing line for more than five seconds? Look up to see what that new alarm is? Write something on scratch paper? Answer the phone? Poof! Start over from scratch, scrub. “It’s for safety.” Fuckin’ chowderheads.
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I just finished a book set in about 1960 where a freighter crosses the Atlantic from the New England area back to England. The weather is crap the whole way, so their navigation is by DR and what RDF bearings the radio operator, who was also the author of the book, could produce.
He was getting bearings at a far greater range than usual and the skipper distrusted his fixes. They finally got in radar range of some coastal features near England and the RDF fixes were proven to be correct.
My questions would be: Would anyone today try and DR their way across the ocean until in RDF range and then radar range? I was an ace RDF bearing taker when I was a wee lad, but the RDF is long gone and I think the beacons are long gone too. If forced into this I would have to find AM or LW broadcast stations to take bearings on. I am not even sure such stations are still charted, I need to go look.
Good book BTW 
The DF sets from my memory didn’t receive frequencies above 500Khz . I don’t know if this was a cunning plan to prevent young officers from listening to the radio.
Mine would work up to 3 MHz. Aircraft sets usually work up to 1.8 MHz. YMMV obviously, but removing the ability to home in on broadcast stations and other vessels on 2182 reduced its utility for sure.