PICKETT & ECKEL, Alhambra, California / USA (1947)
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SCALES of the » ALL METAL DECI MULTIPHASE LOG LOG « Model 3
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Front Side [ white on black ] Back Side
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1/N1 1/10^0.001X
3rdRoot(X< 1;4;7 Digits,.. >) 1/N2 1/10^0.01X
3rdRoot(X< 2;5;8 Digits,.. >) 1/N3 1/10^0.1X
3rdRoot(X< 3;6;9 Digits,.. >) 1/N4 1/10^X
DF πX DF/M X/log(e) = X/M
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CF πX CF/M X/log(e) = X/M
T tan(0.1X); cot(0.1X) Explanations
ST arc(0.01X) how to find the location
S sin(0.1X); cos(0.1X) of the decimal point
[CI] [1/X] [CI] [1/X]
C X C X
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D X D X; [ Co = 10s-Complement ]
[DI] [1/X] N1 10^0.001X
sqrt( X < ODD-No-Digits > ) N2 10^0.01X
sqrt( X < EVEN-No-Digits > ) N3 10^0.1X
N4 10^X
REMARKS:
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The CURSOR shows a Serial(?)Number = F122178 on its top side.
The DF/M-Scale is folded at 1/M where e = 2.71828 = EulerConst.
M = lg(e) = 0.43429 and 1/M = ln(10) = 2.30259 IT FOLLOWS:
Using the D-Scale X, the N-Scales result in Power-of-10( X )
Using the DF/M-Scale X, the N-Scales result in Power-of-e( X )
Using the N-Scales X, the D-Scale result in lgX
Using the N-Scales X, the DF/M-Scale result in lnX
Later this idea is repeated in the famous Slide Rule N4-ES
EXAMPLE of using [ Co = 10s-Complement ]-SCALE with the X-Scale:
lg(0.01) = -2 = [8] - 10 ====>>> lg( 1/N ) = [Co] - 10
Historical Remarks ...
This old model is made of magnesium alloy. For restoration it
had to be disassembled, the oxidized layers scratched away and
VASELINE was applied to all sliding parts. The SR came in a worn
gray soft-plastic case to hook on the user's belt - typical for
the USA: As seen in the "Western Movies" ready for a "quick draw"
impressum:
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© C.HAMANN http://public.BHT-Berlin.de/hamann 07/09/13
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