7265 Lock In Amplifier

[RoGeorge]

The Signal Path channel has at a few videos about lock-in amplifiers, including some experiments:

TSP #107 - Tutorial, Teardown & Experiments with Stanford Research SR530 Lock-in Amplifier
https://youtu.be/rzzliN_vTKs

TSP #147 - Teardown, Repair & Experiments with an EG&G Instruments 7265 DSP-Based Lock-In Amplifier
https://youtu.be/kNnc-lDHtrM

TNP #20 - Teardown, Repair & Experiments with Stanford Research Systems SR830 DSP Lock-in Amplifier
https://youtu.be/figDqnsQD88

I don't have a LIA, but for less sensitive measurements, an oscilloscope in averaging mode can be used as a LIA (when a clean sync signal is available): 
https://www.eevblog.com/forum/projects/oscilloscope-with-trace-averaging-as-a-lock-in-amplifier-(rigol-ds1054z)/