ESI's Model 2100/2110 Auto LRC Meters are two extremely versatile impedance measuring instruments. They feature variable test frequencies (~3000), programmable test-signal levels, component sorting, and CRT displays. They measure inductors (L), resistors (R), capacitors (C) , and display up to 10 impedance characteristics in 26 different combinations. Basic accuracy of 0.05% added to the widest ranges available for passive component measurements make the 2100/2110 the most informative impedance measuring instruments available today. Mass storage for test parameter setups and measurement results is the feature that set the Model 2110 apart from the Model 2100. The 2110 has a cassette tape loader that uses mini-cassette tapes for storing and reloading test parameter programs. The 2100/2110 measurement system is basically composed of a frequency selectable, digital sinewave generator, a test-level regulator, precision range resistors, a phase-sensitive voltmeter, and a charge balancing analog-to-digital converter. All measurements, calculations, and displays take place under the watchful eye of the 2100/ 2110's Z80 microcomputer.