F.416 Data Sheet MJS-p-0435

back to Collection Data Sheets

T&T Electric, The Fast Calculator, 1938

Serial Number or Date Stamp:

Country: USA

Primary construction material: Al

Case included?: yes

General Description: Specialty circular electro slide rule

Length of 1 decade = 3 in, and overall scale length = 9 in. The largest physical dimension is 7 in.

Front Scales: Gauge [ Current PctDrop ] [ WireSize ] Length

Back Scales: HP [ Current ]

Notes: Wire Voltage Drop calculator; Copyright 1938, Frank A. Short, Los Angeles, Patents Pending; HP calcs on back

References: https://followingtherules.substack.com/i/172224670/electricians-slide-calculators-after-1910

Date Acquired: 07/07/2026