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    Re: A-12 bubble sextant
    From: Geoffrey Kolbe
    Date: 2005 Nov 25, 07:13 +0000

    At 22:50 24/11/2005, you wrote:
    >Dear list members,
    >Here are two questions for the A-12 Link bubble sextants specialists or owers.
    >The positionning pin on the spider that is linked to index mirror arm
    >shaft is not abeam of the recording drum groove. Therefore in this
    >position it is impossible to remove the recording drum to install a new
    >one or proceed to some maintenance action like changing the bulb that
    >provide light to the vernier scale or changing the lead that marks the
    >recording drum. Is this issue common with A-12s and can someone explain
    >how to position this recording pin/spider so that it can moved abeam the
    >drum groove to enable removal of this latter? Do I have to pull on the
    >spider? with a specific tool ?
    All you need is your fingers. The "spider" with the three pins is on a
    light spring loaded rachet with respect to the positioning pin on the
    central shaft. Just lift the spider outward, away from the sextant, and
    rotate to the correct position.
    >The shades holding bracket seems to be stuck on the i! ndex mirror arm
    >shaft rotating with the mirror whenever the mirror is rotated with the
    >drum. I think it should be able to be set to any position relative to the
    >index mirror. Is this problem a common issue with A-12 and how do you
    >recommend to deal with it and free the bracket from the index mirror shaft?
    Not a problem I have had with either of my two A-12 sextants (or rather,
    octants). Do you have a manual? Sounds like you may have to dis-assemble
    the index arm assembly and free off the shades.
    Geoffrey Kolbe
    >Music Unlimited - Access over 1 million songs. Try it free.
    Border Barrels Ltd, Newcastleton, TD9 0SN, UK
    Tel: +44 (0)13873 76253   Fax: +44 (0)13873 76214

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