Measurement

This is a one-term course about basics of measurements which I tought from 2014 to 2016. It comprised of a short course of lectures followed by laboratories. Below are some materials I used for this course, which I hope could be usefull.  

 

Lecture Handouts

  1. Propagation of errors

  2. DC electrical circuits

  3. Noise in electrical ciruits

  4. Chi-squared test

  5. AC electrical ciruits

  6. Principles of lock-in detection

  7. Modulation techniques

  8. Priniciples of heterodyne detection

  9. Amplifier noise

 

Laboratories

Week 1: Measurements of free fall acceleration (Experiment I)

We used the simplest measurement devices such as a meter stick and stop-watch to measure the acceleration of a free-fallen body.

 

Week 2: Measurements of free fall acceleration (Experiment II)

We used a more sophisticated setup employing photo-diodes and oscilloscope to repeat measurements of acceleration of a free-fallen body.

 

Week 3: Measurements and analysis of rate of random events

We used home-made cloud chambers to observe tracks of high-energy particles in cosmic rays, counted their rate and checked if it obeys the Poisson statistics using the Chi-squared test. 

Here is about 10 min long movie made by a student and her analysis of the counted rates.

movie1 movie2 movie3 movie4 Analysis

 

Week 4: Small resistance measurements

We studied techniques to accurately measure very small resistance (<1 Ohm). Then we used these techniques to measure the resistivity of copper and compare with known values.

 

Week 5: Large resistance measurements

We studied techniques to accurately measure very large resistance (>109 Ohm). 

 

Week 6: Pirani pressure gauge project

We built and calibrated a Pirani pressure gauge based of resistance measurements of a tungsten wire.

 

Week 7: Low level measurements: Introduction to Lock-in Amplifier

We studied basics of lock-in amplifier and tried to improve on our resistance measurements.  We also studied different sources of noise.

 

Week 8: Tutorial on remote control of instruments and LabView programming

An intense four-hour tutorial on GPIB interface and LabView programming.

 

Week 9: Analysis of AC circuits

We used the lock-in amplifier and remote control to measure characteristics of common AC circuits.

 

Week 10: Using modulation techniques

We  studied different modulation techniques to improve signal-to-noise quality of our measurements.

 

 Week 11: Noise analysis of RF amplifiers

We measured and compared noise characteristics of RF amplifiers.

 

Week 12: Quartz Microbalance

We used different RF techniques, such as modulation and heterodyne detection, to measure resonance characteristics of a quartz microbalance (QM). Then we used QM to measure a tiny mass (< 10-6 kg) of material.