Digital sextant

dLj

.
Mar 23, 2017
3,373
Belliure 41 Sailing back to the Chesapeake
I didn't see any prices on their web page. I wonder who would want one of these? Kind of the worst of both worlds? You need modern electronics to run a system that doesn't give the accuracy of modern electronics... Maybe I'm just a cynic...

dj

p.s. looks like I type more slowly than others here.. ;)
 

capta

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Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
Ugh. Why ?!
If you want electronics then just use GPS.

- electronics hate water
- taking a sight is less accurate.

Lets combine both and lose the advantages of either !
:poop:
Ugh. Why ?!
Have you ever tried to snap a sight between clouds or at night? Have you ever had to get a sight in really rough water? You might have noticed it was a tad bit difficult to keep both the object AND the horizon properly aligned up while the boat is trying to chuck you overboard?
An electronically stabilized horizon would be a blessing to small boat sailors, don't you think? And if that gizmo could reduce the site too, that would be a godsend. However, since I no longer have to tote my sextant and nav gear all around the world, I'm happy enough with a couple of GPS units. Sextants were for when we had to, not for instead of, or even as a back up system for GPS.
 
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Likes: jon hansen
Jun 14, 2010
2,081
Robertson & Caine 2017 Leopard 40 CT
Ugh. Why ?!
GPS satellites are controlled by the US DOD and/or the Russian military (GLONASS). Either one of those can be modified or turned off selectively at the whim of their respective commanders. Also potential exists for those systems to be sabotaged or to come under military/terror attack.
 
Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
Sextants were for when we had to, not for instead of, or even as a back up system for GPS.
That is my point.

I didnt see mention on that site, that says it does t anything other than doing the calculations for you. Nothing about an electronically stabilized horizon.

I dont see any advantage other than speed. (Which admittedly helps)

You still end up with a sextant that inherently gives an inaccurate fix (compared to gps) combined with moisture volatile electronics. The latter of which, is not great for a device for backup.
 
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Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
GPS satellites are controlled by the US DOD and/or the Russian military (GLONASS). Either one of those can be modified or turned off selectively at the whim of their respective commanders. Also potential exists for those systems to be sabotaged or to come under military/terror attack.
That is a case for having sextant as backup. Not having an electonic one.
 
Aug 12, 2018
163
Hunter 26 Carter Lake, Colorado
Looks like it does quite a bit for you, actually, if you go look their web site.

It does seems like if you have a serious reason for using a sextant more than just casually or infrequently it might be interesting.
 

capta

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Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
That is a case for having sextant as backup. Not having an electonic one.
If you are not using a sextant continuously, it will take most people at least 3 to 5 days to get decent sights. It certainly is not like riding a bike.
I think if the all the GPS systems are turned off at once, you'll have a lot more to worry about than your current position.
 
Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
If you are not using a sextant continuously, it will take most people at least 3 to 5 days to get decent sights. It certainly is not like riding a bike.
I think if the all the GPS systems are turned off at once, you'll have a lot more to worry about than your current position.
Not sure what your point is.

Worldwide GPS shutdown is unlikely, but if it happens we have bigger issues ?
A sextant, even one that does the math for you after taking a sight, is difficult to use accurately ?

Agreed.

My point is that taking a device that is inherently difficult to use and inaccurate..
..Then making it partially easier to use while still being inaccurate, and adding additional complexity and a possible failure vector.. Is a strange idea.
 
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dLj

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Mar 23, 2017
3,373
Belliure 41 Sailing back to the Chesapeake
Back in the early days of the GPS constellation deployment I was doing some work as a surveyor using GPS. This was the 1990's don't recall the exact year. At that time I would have to schedule field surveying trips weeks in advance as you had to look for a time period when you had enough satellites visible above a certain angle on the horizon. So I had scoped out a particular day when I could go survey this particular location. The equipment had a program in it that would tell where all the satellites would be for a given day/time months in advance. So I scheduled the meeting and a couple days before the day, I decided to just double check to make sure all the satellites were still projected to be where they'd been projected to be. Low and behold, that was not a single satellite visible anywhere from the East Coast of the US. That was a first, and especially that there were 0 satellites to be found. So I plugged in several lat/long starting points and low and behold the full constellation of satellites were located over, I think it was Iran, but that neck of the woods anyway. Sure enough a couple days later news was there was a military operation happening there. If someone had been using the GPS system in the Atlantic ocean at that time, they sure wouldn't have had much signal!

dj
 
Sep 8, 2020
48
Merit 22 Honker Bay
I've used my sextant to lay out foundations and measure trees. Never for navigation. Never bought the almanacs.
 
Mar 20, 2015
3,094
C&C 30 Mk1 Winnipeg
If someone had been using the GPS system in the Atlantic ocean at that time, they sure wouldn't have had much signal!
And localized jamming is also possible.

But, in the ensuing 30 years, airlines and other non miltary organizations and individuals have become dépendent on GPS.
Self driving cars will also be an issue.

More accuracy and public reliablity is needed for that reason.

Hence we have GPS II and GPS III and importantly Elon Musk's Starlink (which is meant for Internet access but can handle very precise geolocation, and is evidently much harder to jam).

Personally i would be more worried that my electronic hardware fails normally, or due to something like a lightning strike, power surge etc. It happens all the time.
My cell phone died yesterday... No nefarious or military intervention needed.
 
Sep 25, 2008
1,096
CS 30 Toronto
Bring more than 1 GPS. Should cost less than this gizmo. What the Hell, just wait for black Friday and get a bunch for cheap.

If the government(s) jam the GPS, the world is at war. No point trying to figure out where you are. Rum is more important than GPS.
 
Jun 14, 2010
2,081
Robertson & Caine 2017 Leopard 40 CT
If the government(s) jam the GPS, the world is at war.
It's already at war. IMHO - the Solarwinds cyberattack is more damaging to the US (from a strategic perspective) than the Japanese attack on Pearl Harbor.
 
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