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PICKETT   MODEL 3   ( 10" / 25 cm Scales )
Old Model :   Made of Gray Magnesium Alloy



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.beuth-hochschule.de/~hamann   07/09/13