The Type 1633-A Incremental Inductance Bridge (Figure 1-1) is designed to measure inductors and resistors, both linear and nonlinear, over a wide range of ac and dc signal levels. Direct-reading measurements can be made over a broad frequency range. 1.2 DESCRIPTION. 1.2.1 GENERAL. The Type 1633-A Incremental Inductance Bridge includes a unique bridge circuit and a highly selective detector. It is direct reading in series inductance (Ls) and either series resistance (Rs) or storage factor (Q) at nine commonly used frequencies between 50 cps and 15.75 kc. It features single-knob controls for the measurement of L, R, or Q, and combines simplicity of operation with very high voltage- and current-handling capabilities. The signal losses in the bridge are small; thus the voltage and current through the unknown are nearly identical in both amplitude and waveform to the respective voltage and current applied at the GENERATOR terminals. In many instances measurements can be made while the inductor is actually operating in its circuit.