We have described a simple and inexpensive digital phase-sensitive detector using a low-cost AVR microcontroller. To store a large number of data, we have added external memory (RAM) to the microcontroller. A message passing interface daemon-based software has been implemented to control the whole operation. Performance of the system has been tested using precise signals generated through a D/A converter controlled by an 8085 microprocessor. The phase resolution of the system has been reported to be better than . This phase-sensitive detector would be very useful for low-budget laboratories that deal with low-frequency AC signal applications.
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2020
American Association of Physics Teachers
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