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SR865A Lock-In Amplifier


The SR865A Lock-In Amplifier offers superb performance and outstanding value. It's what you’ve come to expect from a Stanford Research Systems lock-in amplifier. With 4 MHz frequency range, time constants from 1 µs to 30 ks, very low noise front-end amplifiers, and a modern, intuitive user interface, the SR865A is the ideal choice for any synchronous detection application.

With over 30 years of lock-in design experience SRS has made every effort to optimize each detail of the SR865A. From a hefty toroidal transformer that eliminates switch-mode noise to iOS connectivity that brings the lock-in to your cell phone to advanced DSP filters that eliminate more noise while speeding up your experiment, the SR865A is truly the ultimate lock-in amplifier.

Please see manual.


·  1 mHz to 4 MHz

·  Low noise voltage & current inputs

·  1 µs to 30 ks time constants

·  High bandwidth outputs

·  Touchscreen data display

·  10 MHz timebase input and output

·  GPIB, RS-232, Ethernet and USB

·  HDMI video output

Created February 26, 2020, Updated April 5, 2022