previous <<==>> next

PICKETT  803-T/-ES  ( 10" / 25 cm Scales )

PICKETT & ECKEL, Chicago, Illinois / USA                     (1948)

SCALES  of  the  » ALL METAL LOG LOG DUAL BASE «   Models 803-T/-ES
Front Side                                                Back Side

                                    LL0     exp(+0.001X .. +0.01X);
sqrt(X<  ODD-No-Digits >)                    exp(-0.001X .. -0.01X)
sqrt(X< EVEN-No-Digits >)           LL1       exp(+0.01X .. +0.1X);
K                          X3                  exp(-0.01X .. -0.1X)
A                          X2       DF                           πX
B                          X2       CF                           πX
S        sin(0.1X); cos(0.1X)       CIF                        1/πX
ST                 arc(0.01X)
T                   tan(0.1X)       L                           lgX
CI                        1/X       CI                          1/X
C                           X       C                             X
D                           X       D                             X
DI                        1/X       LL2           exp(+0.1X .. +X);
CFM                       X*M                      exp(-0.1X .. -X)
                                    LL3            exp(+X .. +10X);
                                                    exp(-X .. -10X)
Models 803 have the same scales as the later Models N803 - but here
all are black.  They came with a leather case, which can be clipped
on the user's belt - typical for the USA:  As seen in the  "Western
Movies" ready for a "quick draw".

The models are made of aluminum.  The typical "Pickett-Yellow" has
an  "-ES"-Extension  in  the  model-number,  means  "Eye-Saver".
The white one has a  "-T"-Extension,  stands for  "Traditional".

The term "SYNCRO SCALE" stands for the combined LogLog scales:
They are designed as a uniquely, split long scale, and, because
LL+/- are reciprocal, 2. & .5 (eg.) share the same tick.

The term "DUAL BASE" means:
Using the D scale X, the LL scales result in Power-of-E( X ).
Using the CFM scale X, the LL scales result in Power-of-10( X ). 
< where E=2.71828 ;  M=lg(E)=0.43429 ;  1/M = ln(10)=2.30259 >

                    Historical Remarks ...
© C.HAMANN    11/08/12