!Under construction!
Lock-in measurement using virtual instruments
The widely spread lock-in technique allows very high sensitive measurements even the signal can be extracted from the magnitudes greater noise. The commercially available lock-in amplifiers are relatively expensive, so we have developed cost-effective, virtual instruments. In our work we have assemble some easy to build, open-source measurement system based on the lock-in technique and what we also use successfully in our academic education, research and development work.We have also built a practice in the context of an Engineering Information Technology MSc course to measure the volume resistivity of different types of wires. The lock-in measurement implemented on NI hardware with supports of 4-wire measurement technique allows high precision measurement with 100 μΩ resistivity resolution.
The work had sent to the NIDays 2014 conference.
Hardware descriptions
The block diagram of the lock-in system.
Photo of the lock-in system implemented on NI_USB_6211.
Software download
- LabVIEW software of the lock-in system implemented on NI_USB_6211
- LabVIEW software of the lock-in system implemented on NI_cDAQ
- LabVIEW simulation of the base of the lock-in