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) REMARKS: =================================================================== 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 ... impressum: ******************************************************************* © C.HAMANN http://public.BHT-Berlin.de/hamann 11/08/12 |