## ECT246 Week 6 ilab

Lab 6 – Filters and Oscillators

By

Student’s Name

ECT246 Electronic Systems III with Lab

Professor’s Name

DeVry University Online

Date

Part A-Active Filters

Week six addresses the concept of active filters and oscillators.  The low, high, bandpass and notch active filters, their circuits, and operating parameters are covered.  The Wein-bridge RC oscillator, its configuration, operation and circuit is discussed.

TCO #6:

Given an application requiring active filters calculate, simulate and measure filter characteristic of a low-pass, high-pass, band-pass, and notch filter.

A.   Identify the gain-versus-frequency response of basic filters.

a.    Draw the frequency response of a low-pass, high-pass, bandpass, and a notch filter.  Label each axis, the critical frequency, bandwidth and the 3-dB point.

Low                                                   High

Band                                                 Notch

b.    What is the “order” of a filter?  How is an order created?

B.   Simulate the frequency response of an active low-pass filter such as a Butterworth filter.

a.    Given the following circuit, calculate the critical frequency and the closed-loop gain.

= _________   = _________

b.    Download “ECT246_Week_6_Low1.ms” from Doc Sharing, week 6.  Run the simulation.  Use the Bode Plotter to find the -3-dB point and determine the critical frequency.

= _________ @ -3 dB

c.    Compare the calculated value to the simulated results.

C.   Prototype the active single-pole low-pass filter and measure and sketch its frequency response, compare and contrast the simulated and measured results.

a.    Prototype the active single-pole low-pass filter in the diagram above using a LM741 op-amp.

b.    Connect a frequency generator to the input of the filter.  Set the frequency generator’s output to a sine wave at 100 mV peak and as close to 0 Hz as possible.

c.    Connect channel 1 of an oscilloscope to the input and channel 2 to the output of the filter.

d.   Vary the input frequency according to the chart below and record the input and output voltage in the table.  Calculate the other values.

Frequency (Hz)

Input Voltage (peak)

Output Voltage (peak) Gain

Gain dB

1

10

100

1k

10k

100k

500k

e.    Using the Graph Paper.doc file located in Doc Sharing, week 6, plot the frequency response of the circuit.

f.     Locate   for the filter.  Compare its value to the calculated and simulate results.

D.   Simulate the frequency response of an active single-pole high-pass filter such as a Butterworth filter.

a.    Given the following circuit, calculate the critical frequency and the closed-loop gain.

= _________   = _________

b.    Download “ECT246_Week_6_High1.ms” from Doc Sharing, week 6.  Run the simulation.  Use the Bode Plotter to find the -3-dB point and determine the critical frequency.

= _________ @ -3 dB

c.    Compare the calculated value to the simulated results.

E.   Prototype the active single-pole high-pass filter.  Measures and sketch its frequency response.  Compare and contrast the simulated and measured results.

a.    Prototype the active single-pole high-pass filter in the diagram above using a LM741 op-amp.

b.    Connect a frequency generator to the input of the filter.  Set the frequency generator’s output to a sine wave at 100 mV peak and as close to 0 Hz as possible.

c.    Connect channel 1 of an oscilloscope to the input and channel 2 to the output of the filter.

d.   Vary the input frequency according to the chart below and record the input and output voltage in the table.  Calculate the other values.

Frequency (Hz)

Input Voltage (peak)

Output Voltage (peak) Gain

Gain dB

1

10

100

1k

10k

100k

500k

e.    Using the Graph Paper.doc file located in Doc Sharing, week 6, plot the frequency response of the circuit.

f.     Locate   for the filter.  Compare its value to the calculated and simulate results.

F.    The active two-pole band-pass filter below consists of a low-pass and a high-pass filter.  Predict the critical frequencies.

a.    Given the following circuit, calculate the critical frequencies and the closed-loop gain.

= _________   = _________  = _________

b.    Download ECT246_Week_6_Band1.ms, and run the simulation.  Use the Bode Plotter to find the -3-dB point and determine the critical frequencies.

= _________ @ -3 dB;       = _________ @-3dB

c.    Compare the calculated value to the simulated results.

G.   Prototype the active two-pole band-pass filter consisting of a low-pass and a high-pass filter and predict the critical frequencies.  Compare the results with the simulated values.

a.    Prototype the active single-pole band-pass filter in the diagram above using a LM741 op-amp.

b.    Connect a frequency generator to the input of the filter.  Set the frequency generator’s output to a sine wave at 100 mV peak and as close to 0 Hz as possible.

c.    Connect channel 1 of an oscilloscope to the input and channel 2 to the output of the filter.

d.   Vary the input frequency according to the chart below and record the input and output voltage in the table.  Calculate the other values.

Frequency (Hz)

Input Voltage (peak)

Output Voltage (peak) Gain

Gain dB

1

10

100

1k

10k

100k

500k

e.    Using the Graph Paper.doc file located in Doc Sharing, week 6, plot the frequency response of the circuit.

f.     Determine , , and the bandwidth for the filter.  Compare its value to the calculated and simulate results.

H.   Explain the operation of a notch filter.

a.    Explain the operation of a notch filter.

b.    Draw the frequency response curve for a notch filter.

Part B- Oscillators

TCO#7:

Given an oscillator application, such as a tone generator, determine the operating parameters and calculate and measure the oscillator’s voltage, frequency and relative stability.

A.   Relate the principles of an oscillator using a block diagram and explain Barkhausen criteria.

a.    Draw a block diagram of an oscillator.

b.    Explain the relationship between feedback, phase shift and oscillation

c.    What is Barkhausen criterion?

d.   What three conditions must be met for oscillation to occur?

B.   Calculate and analyze the operation of an oscillator using RC feedback, such as a Wien-bridge oscillator.

a.    Given the Wien-bridge oscillator in the diagram below, calculate the resonant frequency.  Assume   = 0.

= ________

b.    Determine the closed-loop gain.

= _________

C.   Simulate an RC feedback oscillator, such as a Wien-bridge.  Record the oscillation frequency and compare the results with the calculated values.

a.    Download “ECT246_Week_6_Wien1.ms” from Doc Sharing, week 6.  Run the simulation.  Use the oscilloscope to determine the resonant frequency.  Adjust   if necessary to obtain oscillation.

= ________

b.    Compare the calculated value to the simulated results.

D.   Prototype the RC feedback oscillator, such as a Wien-bridge.  Measure the frequency of oscillation and compare the results with the calculated and simulated results.

a.    Prototype the Wien-bridge oscillator in the diagram above using a LM741 op-amp.

b.    Connect an oscilloscope to the output.  Apply power and measure the resonant frequency.  Adjust   as necessary to obtain oscillation.

c.    Compare the measured values to the calculated and simulated results.

d.   Connect a speaker to the output and observe the results.

e.    Substitute different values for   and/or   and observer the results.

Part C-Filters and Oscillator Simulations

1.   The circuit below is a two-pole high-pass Butterworth filter.  The upper critical frequency should be 1.12kHz.  Find the required value for R4 and the closed loop gain. Verify the circuit operation in Multisim. Make the necessary changes to the circuit and verify its operations.  The Multisim file (ECT246_Week_6_Two_high_trouble.ms) can be found in Doc Sharing, week 7.

The R4 value should be _______; Acl = ___________

2.   Given the following circuit.  What is the frequency of oscillation?  What is the closed loop gain?  The Multisim circuit (ECT246_Week_6_Wien2.ms) can be found in Doc Sharing, week 6.

= __________

= __________

At what value of    does the output begin to clip? __________

At what value of   does oscillation stop? _________

Example Bandwidth calculations

The bandwidth is defined as the:

Power- ½ power points

Voltage- .707 *Vmax

Current- .707*Imax

db- 3 db down from the max db level

f (Hz)                                  Gain            Gain(Db)

1                 56mV          320mV        5.71            15.1

10               64mV          320mV        5                 14

100             112mV        1.28V          11.42          21.15

1k               112mV        1.28V          11.42          21.15

10k             160mV        1.20V          7.5              17.5

100k                                                  3                 9.54

If the above data were taken the bandwidth  would be at:

Since these are voltage gains .707*Vmax

11.42 *.707 = 8.1

After plotting the graph we need to go below 100 Hz and read the frequency that the gain is 8.1. This is f1

Then go above 1k until the gain is 8.1 and read that frequency. This is f2

Bandwidth = f2-f1

If it is in Db then the bandwidth would be at the 21.15DB-3Db or 18.15Db

This should be the same points:

Semilog Point Plotting Example

This is semi log paper, note the bottom horizontal scale is frequency, and always gets 10 times larger on the next decade. There are no zeros on the graph.  10^0 = 1 so that is the first number, 10^1 = 10 so we jump from counting 1’s to counting 10’s, for example 1,2,3,4,5,6,7,8,9,10, 20,30 etc.

The vertical scale is gain in decibels and uses a linear scale.

The point plotted is a frequency of 10 hertz and a gain of 7 db.

## Quantitative

Quantitative vs. Qualitative Analysis Assignments

For this assignment, you will need to perform a quantitative analysis on the below scenario.  Please write your response in a brief APA formatted report.

Quantitative Analysis

You are the manager of desktop support for NASA.  You are responsible for purchasing and managing all of the laptops NASA distributes to employees.  There are 700 laptops currently in service.  All of the laptops randomly leave the building and serve a mobile workforce.  Read the following articles your CIO brought to you for consideration:

http://www.pcworld.com/article/251318/48_nasa_laptops_stolen_in_two_years_a_case_for_better_encryption_practices.html

http://www.pcworld.com/article/181124/laptops_that_go_ghost.html

Compute the SLE, ARO, ALE and safeguard value based on the information in these articles for a report your CIO plans to submit as a solution.  For the safeguard value, find and price an appropriate physical and software solution(s) to safeguard theft and data loss.  Once you pick a product, include a link to the page for pricing and item description.  Present the realized savings in your report and the benefits of the solution you choose for safeguarding the laptops.  Don’t forget to include your equations for ARO, ALE, safeguard value and realized savings calculations.

## discussion 7

Data Security is todays top priority.  Encryption is an effective tool to keep the information confidential.  For an encryption system to work properly, an organization must have good key management.

Using the 3 paragraph structure please discuss one major challenge with key management and a possible solution to the challenge.

YOU MUST POST YOUR THOUGHTS AND IDEAS, BEFORE YOU CAN SEE YOUR CLASSMATES.

You are also required to post a response to a minimum of two other student in the class.

You must use at least one scholarly resource.

Every discussion posting must be properly APA formatted.

## cultural variables

Identify at least two culturally specific variables that impede the adoption of servant leadership within one specific cultural perspective. If you were transferred to that country to work, fully aware that you would encounter those impediments, how do you think they could best be overcome in order to enable servant leadership to be implemented in a culturally-compatible manner?

## Principles of Management

Power Point Presentation

Evaluate the role of strategic planning within the decisions you will be making for the company.

## Case Study

After reading the IMAA article this week on Effective Management of Change during Mergers and Acquisition, review the case study noted within the article on item 7.  It is about a merger between AOL and Time Warner in 2001.  There is a chart listed with the summary that shows the cultural differences between the two companies.  Review that chart.

Using this as an example, conduct some research and find two companies that similarly merged or that was acquired by another company.   Write a two-page summary of the merger or acquisition to include:

1 – the reasons why it occurred and when it occurred

2 –  the approximate size of each company before the merger

3 –  the organizational challenges faced

4 –  was the merger successful or not and why

5 –  the state of the company now

Then include a simple four column chart similar to the example and show at least five cultural elements of the companies, the cultural differences in the two companies before the merger took place and then in the fourth column include the culture now in the acquiring company.   List at least five cultural elements in the chart.

Cultural Element /  AOL culture   /   Time Warner culture    /    Culture adopted

Your written assignment should be no less than 700 words.   Avoid using direct quotes.  Use your own words.    If you do use any direct quotes, increase the length of your paper accordingly.   Use APA citations and ensure you document where you found your data in a separate reference listing.

## Write a 4-6-page examination of three different kinds of architecture that impact your daily life. This assessment allows you to demonstrate your understanding of architecture's influence on personal experience.

Demonstration of Proficiency

By successfully completing this assessment, you will demonstrate your proficiency in the course competencies through the following assessment scoring guide criteria: Competency 1: Describe the historical development of the humanities from the prehistoric era to the present.  Describe how traditional architecture contributes to the experience of spaces we inhabit. Competency 2: Examine the forms of expression that instantiate the arts and humanities.  Describe the spatial and architectural features of familiar places. Apply theoretical principles to the architecture of everyday spaces. Competency 3: Integrate the humanities with everyday life.  Illustrate the influence of architecture on personal experience. Competency 4: Communicate effectively in forms appropriate to the humanities.  Write coherently to support a central idea in appropriate format with correct grammar, usage, and mechanics. Instructions

Write a 4–6-page examination of three different kinds of architecture that impact your daily life. Do the following: Select three different kinds of spaces with which you are familiar in everyday life—places where you live, work, play, exercise, socialize, meditate, or worship.  Describe these spaces in detail, explaining what you observe, feel, think, and do when you are in each. Let your observation include lots of sensory inputs; you may first notice visual elements, but look for characteristic smells or sounds as well. Examine your thoughts and feelings with the same degree of attention—is this a place that uplifts you or drags you down? Consider the activities you pursue in the space, whether they are unique to this space or associated with it in your memory. Include in your essay at least one photographic or other visual representation of each of your three selections. List the theoretical principles of architecture and apply those principles to the spaces you have described.  How do the architectural features of the space help to shape the variety of experiences you have when inhabiting it? Reflect on the traditional forms of architecture and assess how they contribute to what you observe, feel, think, and do in these spaces. Additional Requirements Written communication: Should be free of errors that detract from the overall message. APA formatting: Your paper should be formatted according to current APA style and formatting. Length: 4–6 double-spaced pages. Font and font size: Times New Roman, 12 point.

## WRITE A TWO PAGE PAPER ADDRESSING THE FOLLOWING QUESTIONS (Times New Roman, 12 pt Font, Double-spaced): "IS OEDIPUS A HERO? WHY OR WHY NOT? TO WHAT EXTENT IS OEDIPUS THE ARCHITECT OF HIS OWN MISFORTUNES?

WRITE A TWO PAGE PAPER ADDRESSING THE FOLLOWING QUESTIONS (Times New Roman, 12 pt Font, Double-spaced): “IS OEDIPUS A HERO?  WHY OR WHY NOT?  TO WHAT EXTENT IS OEDIPUS THE ARCHITECT OF HIS OWN MISFORTUNES?

## keep it simple

Application Exercises – IPF PPS.docx (17.036 KB )The IPF PPS is based on a federal perdiem amount that represents the average daily operational, ancillary, and capital costs expended to care for Medicare beneficiaries.  Use the information found in figures 1 and 2 ( below), Tables 6.5-6.9 and figures 6.7 from the test book to complete table 1 and workbooks A&B in order to determine IPF PPS reimbursement for this encounter.

Figure 1: Facility Information

Bed size: 350 beds

Location: Columbus, Ohio

Classification: Rural

Wage Index: .9806

Full Service ED: Yes

Per-diem unadjusted rate (RY 2015): \$728.31

Figure 2: Claim Information

Discharge Date: January 15, 2015

LOS: 14 days

Patient Age: 62

Principal Diagnosis: 295.34*

Paraphrenic schizophrenia, chronic with acute exacerbation

Secondary Diagnosis: 301.6

Dependent personality disorder

Secondary Diagnosis: 250.02

Type II diabetes mellitus uncontrolled

MS-DRG: 885

Psychoses

ECT treatments: 90870

3 units

\$315.55 per unit (RY 2015)