Laurel digital panel meters are available to display frequency in Hz or rate in scaled engineering units such as ft/sec, GPM, L/sec or RPM. A universal dual-channel signal conditioner accepts pulse from proximity switches with PNP or NPN output, TTL or CMOS logic, magnetic pickups, contact closures, low-level outputs from turbine flow meters down to 12 mV, and high-level AC line inputs up to 250 Vac. Rate can also be displayed from process signals such as0-1 mA, 4-20 mA, 0-10 V, from quadrature signals, and from changing resistances in potentiometer follower applications.