"RANGES: 0-70,000 RPM DIGITAL, 0-130.0% RPM DIGITAL AND 0-125% RPM ANALOG; ACCURACY DIGITAL +/- 0.4% OF READING AND ANALOG +/- 1.0% FULL SCALE; READOUT LIGHT DISPLAY, DIGITAL; INPUT SIGNAL TACH GENERATOR MIL-G-9398 ROTATES AT 4200 RPM = 70 CPS WHEN ENGINE IS AT 100% ROTOR SPEED; SAMPLING RATE 0.2 -3 SECONDS"