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  1. #1
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    Question Which is your sextant of choice for small boat navigation?

    I have been saving my pennies for a sextant and wondered which is best for small boat navigation. A used Freiberger Drum, C.Plath, Tamaya, or perhaps a new Astra or Davis?
    I have read reports about the lighter and cheaper Davis Mk25 as being suitable for navigation by some and others who say the opposite!
    Also with chronometers now mostly antiques and those available costing an arm and a leg, do most navigators use a wrist watch these days and is analogue or digital preferred?
    Thanks

  2. #2
    tarik is offline Registered User
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    Default ? Sextant

    Although I have a sextant, and if I really concentrated could use it to get a position, I'm not taking it with me - I have three independent systems of GPS which will give a far more accurate position than anything I could work out with a sextant.

    Good luck


    David

  3. #3
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    How about a Freiberger 'Yacht'? Which is a lightweight version of the Freiberger 'Drum'.
    'The lyf so short
    the arte so long to lerne.'

  4. #4
    Reverend Ludd's Avatar
    Reverend Ludd is offline Registered User
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    Quote Originally Posted by parsifal View Post
    How about a Freiberger 'Yacht'? Which is a lightweight version of the Freiberger 'Drum'.
    Agreed

  5. #5
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    Yes the Freiberger Yacht sextant looks good. I use GPS all the time but would not want to rely on it on a long ocean passage, as the American Military, who own the system reserve the right to turn it off in time of war or to jam it. In order to keep up to speed the military in the US and UK turn it off now and then and practice with it off and no doubt so too do other allied navies. You will see this from time to time in notice to mariners. I was sailing around the north of scotland last year and saw that a naval exercise was being held and from this date to that the GPS would be down and would only be reinstated in the event of an emergency or SAR situation. Last year I think it was MCA conducted trials jamming the GPS signal. A similar exercise in San Diego, saw AIS cease to work and all the ATM's local to the port stopped working as did the traffic lights! Then there is the possibility of losing the electrical system for whatever reason, though in all my years of sailing this has never happened to me. So whilst I would agree that GPS is pretty remarkable when its up, I will be carrying a sextant and sight reduction tables as well. I think it will be interesting to computate my own sun and star sights and compare these with the GPS fix.

  6. #6
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    I have a Freiberger Drum. Had it for 30 years and it has navigated me safely for many tens of thousands of miles around and across the North Atlantic. It is a little heavy, but in rough weather I think that helps to hold it steady. If I bought another today, I'd probably go for the lighter Freiberger Yacht version, but whether that would make sights easier or not is a moot point. Now that the GPS system is so accurate and reliable I hardly ever use it - complete laziness! However, I would NOT go offshore without it. Anything electronic or electrical is vulnerable and likely to give up the ghost at the most inopportune moment - Sod's Law will prevail. I know, I know, we've all got several backups etc etc, and the chances of all of them failing is unlikely. However, a lightning strike on a friend's boat blew every piece of electronic and electrical kit aboard and remagnetised the compass 90 degrees out, so if he hadn't been within sight of land, navigation would've been more than a little tricky. You only ever have to buy one sextant, which you will be able to sell at the end of your sailing career at a good profit (I paid 150 for my Freiberger!), so why not make it part of the essential offshore inventory. And it's the coolest feeling in the world to safely navigate to a speck in the middle of the ocean using just the heavens above you!!
    Happy landfalls to you all.

  7. #7
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    Thank you Jesterchallenger....well said.

  8. #8
    G12 is offline Registered User
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    You could also take a GLONASS set with you if you're worried about the military messing about with GPS.
    http://www.garminnuvi200.com/garmin-...-010-00970-10/

    I work with GLONASS nearly every day, we can either use it standalone or in conjunction with GPS. Using both systems together can produce a much more stable fix as the system can always see more satellites. This is not the sort of thing you'd really notice on a yacht though, we're talking about positions accurate to within 10cm post correction which is pretty damn good for a non RTK receiver.
    The prudent see danger and seek refuge.

  9. #9
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    Hi G12
    I had not heard of GLONASS so thanks for the heads up.
    My point about the military and gps, is that gps is an asset of the american military developed for putting warheads onto targets and is also used by everyone else for peacetime uses such as navigation, banking etc. If the american military or its allies feel that it needs to deploy its assets into theatre, then the gps system will be scrambled and or turned off. When that happens it does not matter what sort of gps system you have it just won't work!
    Presumably GLONASS system was developed by the Russians with similar reasons in mind and could also be scrambled or turned off at a moments notice.
    The military run exercises all the time and when they do they both jam and turn off the gps system in the sectors that they are playing in at the time.
    In peacetime, they kindly let everyone know in advance that they are doing this, through notice to mariners, but in a real situation they will simply re task their birds which will render the commercial systems inoperative.
    A further threat to gps is the use of jammers by criminals, or those simply wanting to avoid being tracked by gps enabled systems. In the US they are trying to crack down on the sale of jammers, which for some odd reason are legal to be sold, but not used. Doh!
    There are documented cases of gps jammers being deployed and causing the commercial gps system to fail in a specific locality, the worry is that this practice could become more common and wide spread.
    I myself carry two hand held gps sets and regularly use gps for coastal navigation, but am aware of its potential limitations. I am in the process of installing gps, linked to AIS linked to VHF DSC, by 0183 NMEA protocol which I feel will be very useful for crossing shipping lanes at night and in poor viz.
    For ocean sailing where I will be out of sight of land for several weeks, I want to navigate with a sextant, watch and tables, manually entering my positions on the chart and comparing these to a fix obtained using gps.
    If for any reason the gps system fails, then I will have a fully working manual system which will allow me to know where I am and how to get where I am going.
    Belt and braces.
    From the comments I have received on this forum it would appear that a used Freiberger Frommel Sextant would be a good bet, or if there is enough dosh, then a new Freiberger Yacht Sextant might the one to go for.
    Thanks for all your suggestions and input.

  10. #10
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    davidjackson is offline Registered User
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    Quote Originally Posted by jollysailor17 View Post
    I have been saving my pennies for a sextant and wondered which is best for small boat navigation. A used Freiberger Drum, C.Plath, Tamaya, or perhaps a new Astra or Davis?
    I have read reports about the lighter and cheaper Davis Mk25 as being suitable for navigation by some and others who say the opposite!
    Also with chronometers now mostly antiques and those available costing an arm and a leg, do most navigators use a wrist watch these days and is analogue or digital preferred?
    Thanks
    I have a CP Sailing Sextant and think it's the dogs' doodahs.

    For time, I use 2 cheap electronic watches, one is digital, the other has hands. Only because that's what I have, if I needed to buy again I'd buy digital, they're easier to read.

    I set them against the time pips several days/weeks before the voyage and monitor regularly to give a good idea about their accuracy. They are generally incredibly accurate. My normal wrist watch is a bit bling, it's made by the Swiss company known to sponsor tennis and yacht racing it's rubbish as a time piece, though.

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