Albert Nestler, Lahr in Baden / Germany (1945)
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VERSION (C)
S C A L E S of the NESTLER » E L E K T R O « Model 37
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Front Side [ inverse / RED ] Back Side
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( 0 .. 25 cm Ruler )
V X * 1.75
(A) PS X2
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(B) KW X2 S sin(0.1X)
[CI] [1/X] S&T arc(0.01X)
(C) X T tan(0.1X)
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(D) X
U X * 5.24
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(LL2) exp(0.1X) = keyed to SCALE A and LEFT CURSOR-MARK
(K) X3
The Slide Rule is LONGER and has a 30 .. 56 cm RULER IN BASE
R E M A R K S : ( 1° = 60' ; 1' = 60" )
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The TRIGONOMETRIC SCALES are divided in MINUTES & SECONDS
The no-named scales are marked here with their common symbols
in brackets: (A),(B),(CI),(C),(D),(LL2),(K).
The U-Scale is folded by ( for calculating "Revol./Minute" )
π / 60 = 0.05236
The V-Scale is folded by the "Specific Resistance of Copper"
sRcu = 0.0175 Ω * mm2 / m
The CU-Marks for "Specific Conductivity of Copper"
sCcu = 57.2 m / Ω * mm2 = 1 / sRcu
The 736-Mark for
1 PS = 0.7355 kW with "Effectiveness"-Marks for
MOT (=Motor) & DYN (= Dynamo)
The Mark sqrt(2g) = 4.429 for "Pressure Hight" calculations
There are 3 different Versions "Model 37" in this collection
In this VERSION (C) the Inverse Scale [1/X] is added ...
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The CURSOR HAIRLINES are symmetrical and in the common
distance (on A-Scale) AREA/DIAMETER (on X-Scale).
The LL2-Scale is placed OVER the CUBIC-Scale and SHIFTED,
that CUBIC "52" is under LL2 "e" = 2 CURSOR SIDE-Hairlines.
Have a look at VERSION (A) & VERSION (B) ...
Historical Remarks ...
The slide rule came in a black cardboard case. It is made of
mahogany with scales on celluloid veneer. The back side's
table with constants was in good shape.
impressum:
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© C.HAMANN http://public.BHT-Berlin.de/hamann 10/10/10
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