lab report eet 2010

EET 2010 Lab Exercise #7 Electronics Principles

1

Multistage BJT Amplifier (Multisim Experiment)

Equipment

1. Multisim

2. Brain

Materials

1. Pencil

2. Paper

Procedure

1. In Multisim, construct the multistage amplifier circuit in Figure 7-1 above.

2. Measure IB, ICQ,  and VCEQ of amplifier stage. (You can show all values at one time

using digital meters if you wish.)

3. Using the oscilloscope to show Vin (Channel A) and Vout (Channel B), determine the

measured overall voltage gain, AV(OA).

4. Using the peak input voltage (Channel A), determine Iin(pk) and using peak output

voltage (Channel B), determine Iout(pk). Use these two values to determine the measured

current gain, Ai(OA).

5. Use your measured voltage gain and current gain to determine the measured power gain,

AP(OA).

EET 2010 Lab Exercise #7 Electronics Principles

2

6. Now, change the values of RE1 and RE2 in the last stage from 125Ω and 700Ω

respectively to 109Ω and 716Ω and repeat Steps 3, 4 and 5.

7. Create a table comparing all measured values from step 1 through 6 to calculated

theoretical values. (Use Q1 = 150, Q2 = 2,400 (overall), Q3 = 150)

8. Create a table comparing all measured gain values (voltage, current and power) to their

theoretical counterparts.

Questions:

1. How did the nominal values of  compare to the measured values?

2. What 3 amplifier configurations were used?

3. Explain the change in voltage gain when RE1 and RE2 were adjusted (Step 6).

4. After changing RE1 and RE2, how did the measured gain compare to the theoretical gain?

Submittal: All sections must be completed digitally. (Not hand-written/drawn)

a. Circuit without meters, probes or o-scope.

b. Circuit showing measured values.

c. Oscilloscope reading – place the measured voltage, current and power gains

directly beneath this screenshot.

d. Calculations (all calculations)

e. Tables

f. Answers to the Questions 1 through 3

Do not be vague or non-specific! Include answers to Questions 1 through 4 above.

Extra Credit: (10 points) Correctly, show all gains as numbers as well as decibels.

1. Title Page (Appropriate information is described in the ‘Format of a Technical Report’ found on Blackboard) 2. OBJECTIVE – This section is in paragraph form comprised of complete sentences stating the purposes for doing the experiment and what theory this experiment was supposed to verify?) 3. PROCEDURE – This section may be numbered statements (use your own words). 4. DATA section including (but not necessarily limited to):

5. DISCUSSION – Complete sentences comparing theoretical values to measured values.

6. CONCLUSION – Complete sentences stating whether or not the experiment was successful, any error, attributable causes for error, any meaningful observations. Do not be vague or non-specific!