EE
2212
PROBLEM
SET 2
S.
G. Burns
Due:
Friday, 5 February
Note
1: Again, a reminder that
some of the WEB browsers such as Firefox and shareware versions of Internet Explorer and Chrome and its derivatives may not display or print SYMBOL and ADOBE
fonts correctly. There are also some
issues with iOS. Also, shareware
versions of WORD and WORD without the embedded symbol font may also have issues in
this regard. For example, 1 kW should
show as k followed by Greek upper case omega. If it displays or prints as 1 kW you have an
issue with all Greek symbols! This could lead to errors with units since micro ”μ” will read as “m” and so forth which yields an
error of 109!!! Be careful.
Note 2: Unless otherwise stated, assume all
operational amplifiers are ideal. Therefore you must use the
summing point constraints as introduced in class to significantly minimize
algebraic complexity.
1. Cascaded amplifier problems. Figures P12.3, P12.5, P12.6, P12.9, 12.14,
and P12.17 (pages
759 and 760) are cascaded operational amplifier circuits. Compute the voltage gain, = vO/vI
for each circuit. Believe it or not,
when you use summing point constraints and the circuit topologies we discussed
in class, the voltage gain computation for each circuit can be done in ONE line! Also for added practice, compute the voltage
gain in dB for each of these six circuits.
2.
Non-linear feedback elements are quite common as we will observe later
this semester. The non-linear circuit in
the feedback network
shown is called an analog
multiplier. The terminal characteristics of the analog multiplier are defined
as shown in the figure.
Show
that this circuit can be used an analog signal divider. That is derive Vo in terms of
Vs1 and Vs2.
3. Active Analog Filter Topologies
You already know from our class discussions that Circuit 1 is an active analog Low-Pass
Filter (31 January/3 February). For each
of the remaining three circuits, state whether the circuit will function as a
low-pass or high-pass filter. Each of
your answers must be accompanied by a brief explanation and justification
incorporating the frequency dependent characteristics of the reactive circuit elements. That is you should look at the asymptotic
impedance of the L and C
if the input signal the frequency is very low or very high. Sketch the expected Bode plot for 20 log(Vo/Vs) as a function of log (f) labeling the corner frequencies. No equations
are required!
4. This is one of my
favorite practical problem topics which may have relevance to you once COVID is
no longer an issue and you no longer have to social distance. You decide to have a loud noisy party
with great music, instead of studying EE 2212 and working on this
problem set or at least delay your studying until you recover from your
party. Suppose your 300 watt sound system yields
an 80 dB signal level as measured by the police in response to a noise
ordinance complaint by a neighbor who you should have invited to your party. http://www.industrialnoisecontrol.com/comparative-noise-examples.htm
(a) If the noise ordinance limit is supposed to be 65 dB
at the lot line, at what power level should you run your sound system?
(b) Suppose you
suggest to the police, politely of course, so that you can avoid getting a minor
for other possible infractions at your
party, that the noise measurement
be taken further away than the lot line.
As an engineering student doing well in EE 2212, how much further away should the noise measurement be
taken? You may assume that measured
audio power is proportional
to 1/r2 where r is the distance from your speakers to the point of
measurement. Your answer will be a
distance ratio, r2/r1.
Many municipalities prohibit
sustained noise that exceeds a certain decibel level. The decibel limits are set according to the
time of day and the neighborhood zoning. When a neighbor complains, police
place decibel level monitoring equipment on an estimated property line and take
a reading. The following WEB link provides some good technical information and
actual dB noise specifications for Minnesota.
https://www.pca.state.mn.us/sites/default/files/p-gen6-
5. Use a six-input summing amplifier design
approach for this design. Since I have been taking guitar
lessons (I am not very good which means I should practice more).
Design the electronic preamplifier for an electric guitar.
There are
six strings on an electric guitar and their frequency and musical note relationships
are shown in the table. Each of the
“humbucker” magnetic pickups for the six strings will be modeled as six
signal sources v1(t), v2(t), v3(t), v4(t),
v5(t), and v6(t).
DESIGN an operational amplifier system (guitar preamp/audio equalizer ) such that
the resultant output, which you would listen to as the sum,
meets the individual string
amplitude specifications given in the last row
of the table. .
Again, assume an ideal
operational amplifier which allows you to use summing point constraints,
however resistor values must be compatible with a mA 741, that
is all resistors
larger than 2kW. Your design must include a detailed,
well-labeled circuit diagram showing six inputs; one for each string’s
“humbucker” magnetic pickup transducer.
String 1 High E |
String 2 B |
String 3 G |
String 4 D |
String 5 A |
String 6 Low E |
v1(t) |
v2(t) |
v3(t) |
v4(t) |
v5(t) |
v6(t) |
f1 > |
f2 > |
f3 > |
f4 > |
f5 > |
f6 |
10 dB |
20 dB |
-6 dB |
6 dB |
26 dB |
30 dB Nice bass boost |
Useful
information; from Low E to High E “Eddy Ate Dynamite Good Bye Eddy”.
FOR YOUR ENGINEERING HUMOR
ENJOYMENT
Some more “wiring” instructions
for a duplex outlet.
These cartoons obtained
from a friend raiding a secret stash of cartoons at a well
known laboratory instrument and computer company.
UNITS ARE ALWAYS AN ISSUE TO REMIND YOU OF THE BASIC CIRCUIT ELEMENT
DEFINITIONS
This may help with your
understanding of DACs and ADCs
To
BBBBBBBBBBBbbbbbbbbbb
N
N
BASE
BTO
SUPPORT YOUR UNDERSTANDING OF dB
And more from my files of good stuff: