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Alex,

There might not be any demand for this, but the factory made some for
the Chinese Navy.  They asked if I could sell some, and I was not
very hopeful. However, we had a space in the catalog at the last
minute, so just stuck it in. We actually had an order two weeks ago
from a Prof at a maritime school who wanted to demo it to students.
It reminds me of the Russian star globe we carried during the cold
war. It was far greater quality than the East German (Freiberger)
one.  In eight years of showing it, we sold only one unit (which is
all we had in stock anyway). Nevertheless, it helped our catalog
stand out from the others who only carried items that generated x$
per square inch of space.

Ken
On Apr 4, 2012, at 4:32 PM, Alexandre E Eremenko wrote:

>
> Ken,
> Yes, it looks exactly as the Soviet model, as far as I can judge from
> those tiny pictures:-)
> I am still surprized: is there really any substantial demand for this
> heavy and expensive toy, I mean demand that is not covered by e-Bay?
> Why else would they make it?
>
> You can certainly solve the same problem will all precision needed
> for practical navigation with a simple plastic station pointer
> you always had, or with a simple computer program.
>
> Besides, there is no place to store this thing in a small boat:-)
>
> Alex.
>
> On Wed, 4 Apr 2012, Ken Gebhart wrote:
>
>>
>> Alex,
>>
>> Yes it is made by the same factory, and possibly is a copy of the
>> Russian model. Your comment is certainly correct, and we are
>> replacing "determine the direction" with "identifies".  As for the
>> two solutions, we didn't want to confuse the reader, or start a new
>> dialog about the math.  Thanks for your comments.
>>
>> Ken
>> On Apr 4, 2012, at 12:56 PM, Alexandre E Eremenko wrote:
>>
>>>
>>> Indeed!
>>>
>>> I am surprized. They do not say who makes them,
>>> Ken, is it by the Astra factory?
>>> The construction seems exactly the same as of the Soviet one
>>> that I have, except that the Soviet one is made entirely of bronze,
>>> and this one of an aluminium alloy.
>>> The box is of slightly different construction.
>>> (Soviet ones on e-bay usually cost a bit less).
>>>
>>> There are several imprecise points in the Celestaire description.
>>>
>>> a) You do not need to measure the DIRECTIONS (bearings) of 3 objects
>>> but only TWO HORIZONTAL ANGLES between them. This is done with
>>> a sextant. (A direction is measured with a compass, and it is
>>> hard, if not at all impossibe to measure with 1' accuracy).
>>>
>>> b) "There is only one solution". There are generally 2 solutions.
>>> The are usually far apart, if one takes the right objects to
>>> measure angles between them, and one of the solutions is usually on
>>> land.
>>> Geometrically, these solutions are the points of intersection
>>> of two circles (position lines). Two circles usually intersect at 2
>>> points.
>>>
>>> Alex.
>>>
>>>
>>>
>>
>>
>>
>>
>>
>> : http://fer3.com/arc/m2.aspx?i=118702
>>
>>
>>
>
>

   

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