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    Re: Do you know this instrument ?
    From: Gary LaPook
    Date: 2024 Oct 30, 11:15 -0700

    I suspect that these were important during WW2 for ships in convoys to maintain their station. I suspect this is now done with radar or AIS.  These pages are from Dutton, 1969

     I recently acquired this Davis rangefinder which works well. 

    When I commanded an M60A1 tank i had a coincidence rangefinder mounted across the turret with the lenses protruding out of each side to give it a long baselength. Accurate out to 3,000 meters. When I  got the newer M60A3 it had been replaced with a laser, more accurate especially at longer ranges.

    The difference is that with a coincidence rangefinder you do not need to know the size of the object sicnce it works on the baselength of the rangefinder. 

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