Aristo Hyperbolog Nr. 0971

The Hyperbolog 0971 was produced in Germany from the mid 1950's until the early 1970's. Fabricated with high grade PVC (Astralon/Aristopal), plastic braces, and all plastic cursor with four gauge lines for quick HP-KW conversion, is a great slide rule for electrical engineering applications, incorporating to the standard logarithmic and trigonometric scales, hyperbolic sine and tangent scales.

This rule has 25 scales: Th, K, A [ B, T Cot, ST, S Cos, C ] D, DI, Sh2, Sh1 on the front face, and LL01, LL02, LL03, DF [ CF, CIF, L, CI, C ] D, LL3, LL2, LL1 on the back face. Something noticeable is the lack in this scales set of the Pythagorean Scale P, so characteristic in the Aristo slide rules.

According with the engraved serial numbers on the specimen shown below, this was fabricated in 1969 in Hamburg:

Click on the next links to see professional panoramic pictures of the 0971 model.

https://www.sliderulemuseum.com/Aristo/Aristo_0971_Hyperbolog_dc2FX4.jpg

References:

• Mosand John: A Brief History of the Aristo Studio Slide Rule. http://www.oughtred.org/jos/Mosand_BriefHistoryOfTheAristoStudioSlideRule.pdf

• Aristo: Product Catalog 1969: https://drive.google.com/file/d/1il3ty5j3n2rC4mHHBqag1jX788X1EmNd/view?usp=sharing

• Aristo-Werke, Denert & Pappe KG: 100 Years of Aristo Slide Rules 1872-1972, Hamburg. 1972. https://drive.google.com/file/d/1AYMhF20TCHU_nUQLkx0RaJ9pNK1vTyic/view?usp=sharing

• Robinson, William K: LISTING OF ALL KNOWN SLIDE RULES WITH HYPERBOLIC SCALES, www.oughtred.org/jos/robinson-hyperbolics-dec06.html