The EG&G 5206 Lock-In Amplifier 200 Hz - 200 kHz is one of the first commercial lock-in amplifiers that can be fully controlled by a computer. An optional Digital Interface allows total programmability of the model and talk/listen operation with other devices on the bus. Computer-controllable functions include sensitivity, averging time constant, phase, operating frequency, offset, dynamic reserve, display mode, and others. Standard features include auto-phasing, auto-ranging, and "sine-wave" response. Also displayable are operating paramters such as the internal-oscillator frequency, the amount of dc output suppression, and the phase shift.