NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: SNO-T tests
From: Bill B
Date: 2005 Nov 21, 19:00 -0500
From: Bill B
Date: 2005 Nov 21, 19:00 -0500
> Here is a sample of backlash measurements done with my 76 SNO-T at 0? altitude > sighting a not so distant power line.The instrument, although clean, could > have been regularly used when in service with the Soviet Navy and therefore I > would not be surprised if some wear had developped in the gears > I guess part of the results spread is due to the operator ageing eyes. JPP With my Astra (3.5X scope) and a power line, both clockwise and anti-clockwise averages are identical. Which on the surfaces sounds good. BUT... If I continue turning in the same direction for 0.2', it still appears in alignment. It clearly leaves alignment between 0.3'and 0.5' of the first perceived alignment. Using some fuzzy math, it would appear the the mean alignment approx 0.1' past the first perceived alignment. Therefore, my spread is 0.2', not 0.0'. Clockwise Touch Leave 57.8 58.0 57.6 58.0 57.6 58.0 57.8 58.0 57.7 58.0 57.6 58.0 Mean Mean 57.7 58.00 Standard Deviation of touch 0.1 Standard Deviation of leave 0.0 Anti Clockwise Touch Leave 57.6 57.2 57.8 57.4 57.6 57.0 57.7 58.2 Mean Mean 57.7 57.2 Standard Deviation of touch 0.1 Standard Deviation of leave 0.2 Bill