Vintage Soviet Circular Slide Rule Logarithmic Ruler KL-1 USSR 1960's Calculator. Circular logarithmic slide rule "KL-1" is intended for solving the most occurred mathematical operations. Calculations of circle square and finding of trigonometric functions of a sine.
Finding of trigonometric functions of a tangent. Finding inverse trigonometric functions (of sines and tangents). Calculation of the area of a circle.
The logarithmic rule consists of the body with two knobs, two clock faces, one of which is going round by means of a knob with black point, and two arrows going round by means of a knob with red point. All the details in the photo. Full set of papers box. The item "NEW Logarithmic Ruler KL-1 Soviet Circular Slide Rule Calculator USSR documents" is in sale since Tuesday, July 27, 2021.This item is in the category "Collectibles\Science & Medicine (1930-Now)\Engineering\Slide Rules". The seller is "anna_antik" and is located in slavyansk. This item can be shipped worldwide.