Hyperbolic Match Output

Number:80a

Maker: PICKETT & ECKEL (USA)

Model: N4-ES Vector - Type LOG LOG Dual - Base Speed Rule

PHOTO

Scales Front:||Three cube root scales ₃√ , DF || CF, CIF, T&T, ST, S&S, CI, C || D, DI, Two sqrt scales √ ||

Scales Back: || LL₁&LL₁, LL₂&LL₂, DF/M || CF/M, Th, Sh&Sh, Ln, L, CI, C || D, LL₃&LL₃, LL₄&LL₄ ||

Gauge Marks: Gauge Marks on scales: π , π/4 , and R are on C, D, CF, DF, CF/M, DF/M, CI, DI, and CIF; e is on C, D and LL3; and marks 1° ' and " are on ST.

Cursor Front:

Cursor Back:

Construction:

Date:

Source: ISRM

Information: A variation of 80. This comes in a special large case to hold the built-in magnifying cursors. The box says, "Pickett rules have been on 3 Apollo missions". Has magnifying cursors on both sides of the rule.