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That is a very good brand, can't tell from the photo what model it is though (plastic or metal?) Looks like it has a card giving errors which is good, make sure there is a tool for adjusting the mirrors. Be nice if the mirrors were in good nick. Point it at the horizon with the arm at 0 degrees 0 minutes and see if the horizon is a straight line, then point it at a star (or a pin point far away) and rock the sextant through an arc and see if the two images split.

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It's a very good German made sextant. Fairly pricey new.
Taking a sighting is fairly simple, although exacting. The more accurate you can get the sighting and the time, the more accurate the position you get. You need the book with the tables as well of course.
BP, I might be wrong, but I think they only made the one yacht sextant and in Aluminium

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that's a full size frieberger drum sextant made in the ddr through the 80's with zeiss optics

 

the friebergers?usually seen  on tm are the alloy 3/4 size yacht sextant - straight bars vs. the curved cut outs

 

i have the highly recommended mary blewett celestial nav book for you :thumbup:

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A good no nonsense sextant, as said they were / are made in the DDR. Zeis Optics are/were one of the best available.

There will be a quite few Merlin nav calculators taking up room in some boaties cupboard, they can be extended into the 2020's as i understand it, worth getting if you can track one down. Of course there maybe be better systems available now.

It is interesting to note that the American Navy is re-instituting teaching Celestial navigation, because all of a sudden someone realised that if the satellites die all their ships are quite literally lost.

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True. Hence the tables above. But BK's post above he was saying for the event of no gps sats. :-)

 

Sats & GPS might die

PC might die

Handheld calc might die

charts and tables might get wet and unusable, or navigator might fall and break sextant.

DR then I guess....

 

Oh yeah, Crew (and or Skipper) might die too!!

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True. Hence the tables above. But BK's post above he was saying for the event of no gps sats. :-)

 

Sats & GPS might die

PC might die

Handheld calc might die

charts and tables might get wet and unusable, or navigator might fall and break sextant.

DR then I guess....

 

Oh yeah, Crew (and or Skipper) might die too!!

Don't worry IT, you're in Open CPN lessons just got longer & more involved!

We'll be talking, ;-) 

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that's a full size frieberger drum sextant made in the ddr through the 80's with zeiss optics

 

the friebergers?usually seen  on tm are the alloy 3/4 size yacht sextant - straight bars vs. the curved cut outs

Actually erice is correct. It's the full size drum sextant and worth about 2x the cost of the yacht sextant.

I don't own a sextant and when ever I see one on trademe, I keep thinking that would be really cool to have. But it is never near the top of my lost. However, I read survive the Savage Sea over Christmas and I was so highly impressed by the guy navigating his family toward land and safety with unbelievable accuracy (although he didn't have a sextant on the life raft) that I though wow have many of us lost an important skill with the relying on of electronics.

By the way, I don't recommend reading a book on being Ships wrecked and fighting for you life in survival while cruising. And even worse, don't read two books on that subject. ;-)

However, I do highly recommend reading the story of the sinking of the USS Indianapolis "In Harms Way" and the story of the Robertson Family and their epic story of their survival after their Yacht was sunk by Orca off Galapagos Islands and they "sailed" their Liferaft and then dingy for 39 days and over 700Miles toward South America.

Found this site for you with a pic and info of both.  https://mdnautical.com/freiberger-sextants/19728-freiberger-drum-sextant.html

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There will be a quite few Merlin nav calculators taking up room in some boaties cupboard, they can be extended into the 2020's as i understand it, worth getting if you can track one down. Of course there maybe be better systems available now.

 

The Merlins must have saved a few arses over the years.

 

https://play.google.com/store/apps/details?id=com.Sightreduction

One of many I'd be thinking. A suss shows some interesting app things.... not that I even know how to get one.

 

If I was new to Sextant Nav I would use paper to work it out, it doesn't need batteries. But a lectronic something to cross check results could be handy.

 

I have a 1 page site workings cheat sheet the ye olde shops captain who taught me gave me way back in the day. I'll dig a copy out.

 

Those Sextants are nice bits of kit BK, go for it.

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I had a Merlin but it died and was junked. Problem with them was if you did not keep the battery current they lost the programming and data. It was designed by a surveyor in Perth, Mike Pepperday. He updated my Merlin after it had lost its programming, later it would not switch on at all.

If you can find an operational one I believe Boat Books in Sydney can reprogramme it

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Celestial navigation is still a major component of the Ocean Yachtmaster curriculum. And they don't allow the use of sight reduction tables. You have to work out the full PXZ triangle equation from sextant readings (at least they do allow a scientific calculator!). I well remember us all spending a Sunday afternoon off Paekakariki beach getting sunset sights. Using a sextant is still a good skill.

And of course an aspect of attaining Cat 1 is some proof the crew know what they're doing.

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