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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Trouble with Kollsman Periscopic sextant - no bubble
From: Ken Gebhart
Date: 2005 Dec 20, 20:11 -0600
From: Ken Gebhart
Date: 2005 Dec 20, 20:11 -0600
On 12/20/05 3:20 PM, "Guillaume BARTHELEMY"wrote: > Thanks for these information; As far as I can see from the drawings which are > at > http://www.geocities.com/petanoz/aviation/celestnav.htm, the bubble chamber is > lacking on my sextant... > But that is surprising, because on mine I wonder how the bubble chamber could > be > fixed,and seen from the eyepiece at that place; indeed, at that place there is > only a very little hole where a very little light is screwed in. > > Best regards > > Guillaume BARTHELEMY > > > > Selon Noell Wilson : > >> I don't know of a manual online but there is a photo at >> http://www.geocities.com/petanoz/aviation/celestnav.htm >> that shows the location of the bubble chamber. >> You may wish to search the Nav-L archives for Kollsman and for the word >> pellicle for some more information on the bubble. >> Regards, Noell >> >>>>> jeanphilippeplanas@YAHOO.COM 12/20/2005 2:26:24 PM >>> >> Hi >> Are you able to power the instrument with 28V? >> JPP >> >> Me Guillaume BARTHELEMY wrote: >> Hi, >> Being new borned in astronomic navigation, I bought on e-bay a Kollsman >> Periscopic sextant. >> Unfortunately, I can't manage to see the bubble throw the eyepiece. Is >> anyone could tell me where is the bubble chamber or could help me. >> Thanks a lot. >> Guillaume BARTHELEMY. >> >> >> >> >> JPP >> __________________________________________________ >> Do You Yahoo!? >> Tired of spam? Yahoo! Mail has the best spam protection around >> http://mail.yahoo.com >> > G, OK, you certainly do have a pendulum with a mirror attached with crosshair. I mistakenly said 12 volts was required, but as another post mentioned... It is 28 volts DC (aircraft power). You can either bunch a lot of batteries together to make that potential, or maybe change the bulb to a lower voltage. The power goes in through a sophisticated fitting, but lacking this, there are 2 pins visible that take the power. Although much rarer, this pendulous mirror is actually much nicer in that the cross hairs can be put accurately on a star without the vagaries associated with using the center of the bubble. Please let the list (or at least me) know how you make out with this. Ken Gebhart