electronics

Using Phase Relationships to Find an Unknown Capacitance in an RC Circuit

Student Manual

This task deals with the determination of an unknown capacitance inside an RC series circuit. You are provided with a Labview file (rcphase.vi) that communicates with a circuit already laid out for you on a breadboard. You can control the input frequency (preferably between 1 and 50 Hz) and will observe the sinusoidal voltages developed across the resistor R and the input voltage. These waveforms will be shifted in time through ∆t. Hence there will be a phase difference ϕ = ω∆t where ω = 2πf, and f is the input frequency in Hz.

Software CodeDownload
Experiment Code1.6C
Version6 January 2016, 2016-v1

Further Readings and References

No references found

Pictorial Procedure

DETAIL

Finding an Unknown Resistance in Series with a Capacitor

Student Manual

An experiment has been set up for you. The arrangement is similar to what is provided in
Experiment 1.6A. We have a resistor R in series with a capacitor C. The capacitor has a
known capacitance. Measure it using the provided meters. A sinusoidal input of amplitude
Vo, and frequency f , is applied and the voltage amplitudes across the resistor VR are measured at various frequencies. The inputs and outputs are through a computer equipped with a data acquisition board. A Labview le is also provided and can be downloaded from the website.

Software CodeDownload
Experiment Code1.6B
Version10 December 2015-2015-v1

Further Readings and References

No references found

Pictorial Procedure

DETAIL

Data analysis with capacitor

Student Manual

The main objective of this experiment is to investigate the time needed to discharge a capacitor and determine the RC time constant of an RC series circuit. Students will also practice how to generate and acquire a signal using the data acquisition system. The voltage across resistor and capacitor will determine the value of the unknown resistor/capacitor.

Software CodeDownload
Sample ResultsCharging of the capacitor
Discharging of capacitor
Curve fitting discharging capacitor
Experiment Code1.6A
Version14 September 2014, 2015-v2

Further Readings and References

No references found

Pictorial Procedure

DETAIL

Data Acquisition and Filter Design

Student Manual

This is a veiled introduction to data acquisition. Furthermore, students will be exposed to the ideas of filtering, noise, sampling and autocorrelation.Students will be required to analyze the autocorrelation of the noise signal, generated from a pseudorandom binary signal. This will be followed by low-pass filtering using a simple RC circuit and calculating the autocorrelation of the filtered signal.

Software CodeDownload
Sample ResultsGain of a low pass filter as a function of frequency
Circuit for pseudo-random noise generation based on shift registers
Experiment Code1.6
Version1st October 2008

Further Readings and References


Pictorial Procedure

1. Provided apparatus

1. Provided apparatus

Daq_2nn

2. Generating a sine wave of 10 Hz with signal generator

3. Connecting a signal generator to the labeled leads of DAQ for acquiring data

3. Connecting a signal generator to the labeled leads of DAQ for acquiring data

4. Setup for Nyquist Sampling Theorem

4. Setup for Nyquist Sampling Theorem

5. All function files must be in the current directory of Matlab

5. All function files must be in the current directory of Matlab

6. Front panel view of nyquist.vi file

6. Front panel view of nyquist.vi file

7. Accessing block diagram window

7. Accessing block diagram window

8. Changing sample rate in the Block diagram window

8. Changing sample rate in the Block diagram window

9. Saving data in nyq.lvm file. You can change the folder path as well

9. Saving data in nyq.lvm file. You can change the folder path as well

10. Circuitry for low pass filter

10. Circuitry for low pass filter

11. In order to change the input peak voltage to 5V, you need to use this configuration

11. In order to change the input peak voltage to 5V, you need to use this configuration

12. High pass filter with 1.3KHz cut-off frequency

12. High pass filter with 1.3KHz cut-off frequency

13. Circuitry for composite signal

13. Circuitry for composite signal

14. Setup for filtering a composite signal

14. Setup for filtering a composite signal

DETAIL

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