Hyperbolic Match Output
Model:Neperlog Hyperbolic No. 691
Scales Front: || L, P, Ch, A || B, T<45° & T<45°, ST & ST, S & S, C || D, Th, Sh2, Sh1 ||
Scales Back: || LL01, LL02, LL03, DF || CF, CIF, CI, C || D, LL3, LL2, LL1 ||
Gauge Marks: π is on A, B, C, D, CF, DF, CI, CIF, ρ', ρ", ρ', and ρ" are on scales C and D, both Front and Back.
Cursor Front: π /4 line is on left over the A & B; 4/π on right over C & D.
Cursor Back: : a mark on right over C and D scales for multiplication by 36 on CF and DF.
Construction: 26.45 cm.; Plastic; Cursor is not framed. Has fixed plastic end brackets and rubber feet.
Source: Gonzalo Martin Collection
Information: There are two lines over all scales on far right and left for the conversion to HP(**) by using C and D scales.