- Reading:
- In the Ulaby/Maharbiz text,
please continue to study Chapter 9, Sections 9.1 and 9.3,
on frequency response and filters.
Also continue to review Chapters 7 and 8.
- Please review solving simultaneous linear equations and
complex number operations with your calculator.
A document and some links are posted on Blackboard under Course Materials that may be helpful.
- The exam dates are set in the
syllabus
as Tuesday, March 1 and Tuesday, April 5.
-
We will have
Lab 1
on January 31 and February 2.
Please bring your textbook to all lab sessions.
We will have
Lab 2
on Feb. 7 & 9, and no lab on Feb. 14 & 16.
- Pete James will hold a review session on
Tuesday, Feb. 1 from 7-8 PM in Dana 305
to answer your questions on using your calculator to solve circuit analysis
problems.
Please see him if you have questions about solving simultaneous linear equations with complex coefficients and complex number arithmetic.
- Please bring your calculator to class on
Tuesday, Feb. 1
Thursday, Feb. 3.
We will have a short quiz on complex number arithmetic and
solving simultaneous linear equations with complex coefficients.
(The date is moved to Thursday so that you can ask questions on Feb. 1
or in lab.)
- Please complete the survey of ELEC 225 topics on Blackboard under Assignments by
Friday, Jan. 28.
- Please click here and solve the
three review problems that are taken from previous exams in ELEC 225 and 226,
and submit solutions in class on Tuesday, Feb. 8.
In the third problem on complex power, the "maximum value of
instantaneous power" refers to the peak value, which may be positive
or negative (choose the largest peak magnitude of the power).
Note also in the complex power problem, the capacitor impedance is -j(120) ohms.
The pdf file is updated with this clarification.
- Please solve the following problem
and submit solutions in class on Tuesday, Feb. 8.
Chapter 7: Problem 7.28 (use Delta-Y transformation)
- Please answer the following questions
and submit your solution in class on
Tuesday, Feb. 8
Tuesday, Feb. 15.
These questions are very similar to the analysis in
Lab 1.
Draw a circuit with a
sinusoidal voltage source vs(t) = 1 cos( w t) (V),
a resistor (R), and a capacitor (C) in series.
Specify the output voltage vo(t) so that the circuit will
be a high-pass filter in the sinusoidal steady-state as
the radian frequency w of the source is varied.
- Find the expression for the frequency response
(or voltage transfer function) H( w ),
which is defined as the ratio of the output phasor to the input phasor.
- Find the expression for the magnitude of the
frequency response, |H( w )|,
and the phase angle, /_ H( w ).
- Make a rough plot of the amplitude gain |H( w )|
versus w.
Do this as a Bode plot of amplitude gain (in dB) versus frequency using a logarithmic scale on the frequency axis.
- Make a rough plot of the phase angle, /_ H( w )
versus w,
again using a logarithmic scale on the frequency axis.
- Find an expression for the cutoff frequency wc
as a function of R and C.
Indicate the location of wc on your Bode plots
in the previous items.
The cutoff frequency is the value at which the magnitude
of the frequency response equals 1/sqrt(2) times the maximum gain
(or reduction by 3 dB on a Bode plot).
- Specify values for R and C that will produce a cutoff frequency
of 1000 Hz.
(Note that wc is in radians/sec, so you need to convert
to Hz!)
Thank you.