Review Exam (Timed)
In the circuit below what AC voltage might a VOM, using the AC function, measure across the secondary of the T1 transformer if the circuit is connected to a 117 V AC wall socket?
11.7 VAC
What number is the pin designated by the arrow in the figure shown below?
12
In the drawing below you would expect what voltage at the output, A?
12.3V
In the circuit below, approximately what voltage would you measure at A if the plug was connected to a117 volt AC wall outlet?
15.5 V
What frequency will the parallel LC circuit be resonant to?
159 Hz
In regards to AWG standards, which gauge of wire has a bigger cross-sectional area?
16 AWG
Which of these is within tolerance for a resistor color coded red, black, red, gold.
1950 ohms
A lead-acid battery cell, when charged, has a nominal voltage of:
2.1 volts
In the drawing below, what is the power produced in the resistor?
20 watts
Hexadecimal 2E is equivalent to a decimal number of:
46
A 3/8-inch diameter by 3/16-inch ceramic disk capacitor marked "47k" is most likely what value?
47pf +/-10%
The sine wave shown is at what frequency?
500 Hz
The "1" in binary number 1000000 carries a decimal weight of:
64
The peak voltage of the below waveform is:
7 V
Which of the following wires has the greatest cross-sectional area?
9 AWG
Which of the silicon diodes below will conduct, given the voltages applied?
A
The input of the op-amp below is a .5 V sine wave (centered about +2 V). What will the output be?
A 1V sine wave centered at about -4V
Of the below, which most determines the value of a capacitor?
A Size of the plates
Which of the below is MOST likely to be the cause of distortion, mostly at high levels, in an amplifier?
A rubbing speaker voice coil
In the United States there are five common classifications of fires, which are:
A, B, C, D, K.
A test plan should contain which of the following?
All of the above
What is the combined reactance of the two capacitors in series in the drawing below?
Approximately 1198 ohms
The disassembled item shown below is a:
BNC connector.
Which would be the MOST likely cause of hum in an amplifier, but only when it is switched to the CD position?
Bad shielded cable from the CD to the amplifier input
Which one of the following integrated circuit or semiconductor devices normally requires the most careful handling to avoid damage by static electricity
CMOS
What is the effect on a varactor (varicap) when the reverse bias voltage is increased?
Capacitance decreases and the tuned frequency increases
The velocity factor in a transmission line?
Compared to free space velocity
If A is low and B is high, and C is low and D is high, what is the output at E?
High
What is a primary advantage of a FET when compared to the bipolar transistor?
High input impedance
How should a fuse be installed in a circuit to insure proper operation?
In series with the load
Which one of the below is a common description of the filter shown here?
Low-pass T
If the gate voltage level that turns on an active SCR drops below the trigger point, while anode and cathode voltages are maintained, what will occur?
The SCR stays on.
a three input NAND has two high inputs and a low input. the output will be high.
True
The formula best used to calculate the opposition to AC current in the following drawing is ...
Xc = 1/2*3.14*F*C
If a co-worker is found unconscious due to electrical shock, after insuring any hazard is removed and verifying there is no pulse, you should next:
if qualified, properly administer CPR after seeking medical assistance
The term for the combination of resistance and reactance that restricts the flow of alternating current is:
impedance
An inductor in an electrical circuit:
impedes the. flow of AC current.
How is a fuse installed in a circuit to insure proper operations
in series with a load
In the circuit below, to reproduce the square wave input more faithfully at the output ...
increase the value of the resistor.
Decreasing the inductance in a series tuned circuit will cause the resonant frequency to:
increase.
The capacitance of a capacitor___________ if the distance between the plates decreases while all other properties of the capacitor remain the same.
increases
A Logic Pulser can be used as a:
inject a signal
Waveguides are not utilized at VHF or UHF frequencies because:
large waveguide dimensions as required at lower frequencies are not practical
An inductor with the same length of wire but whose coils are spaced further apart will have:
less inductance
The magnetic field that surrounds a magnet can best be described as invisible lines of force, and are commonly referred to as:
lines of flux.
If SW1 were to open, the output of the gate circuit shown below will be:
low
Thermocouple outputs measure in the __ range.
millivolt
A logic 1 for a TTL device is
more than 2 volts
The ripple frequency of the output of a full wave rectifier power supply measures the same as the AC input. the section causing this problem is the
rectifier
The voltage rating of a capacitor ____
relates to the maximum voltage that should be applied to it
Carbon microphones are much like variable:
resistors.
Electrons are arranged in _____ around a nucleus
shells
A power supply that is being serviced is found to have several 250 mfd capacitors connected in parallel.To avoid shock from retained charge after disconnecting the power, these capacitors:
should be discharged to chassis ground, with a suitable resistor.
When replacing a DIP chip, _____
use an ESD static grounded soldering pencil or work station
The Y axis of an oscilloscope is:
vertical
Regarding Germanium diodes, they:
have approximately 0.3V forward voltage drop
In the circuit below, the output will be:
high.
Common analog telephone lines, on hook, may be expected to have what DC voltage level on one of the wires?
-48 V
Which is the equivalent to 100 microwatts?
0.1 milliwatts
What is the binary number for decimal number 6?
0110
This DC circuit will require how many RC times to charge the capacitor to 63% of the applied voltage?
1
Which of the below would be the best test frequency for general audio troubleshooting?
1 KHZ
In the circuit below, how much current is flowing in R1?
1 amp
The +5V level of a TTL digital signal is also most frequently called a logical:
1 or high.
one microfarad is equivalent to ______ picofarads
1,000,000
Adding the binary numbers 110111 and 001101 will give which one of the results below?
1000100
Current amounts between ______ and _____ can be lethal.
100mA, 200mA
164 (decimal) converted to binary would be:
10100100
What are three types of materials used in electronics?
Conductors, semi-conductors and insulators
What will happen to the current through a resistor if the resistor value suddenly increases?
Current decreases
Which gate is an OR ?
D
In the illustration below, what component of the coaxial cable is letter "B"?
Dielectric
To properly bias a PNP transistor, which voltages appear correct?
E=-1; B=-1.7; C= -10
What does the acronym ESD stand for?
Electrostatic Discharge
Cables of different impedances may be combined for short runs?
False
When measuring power to a speaker, a doubling of the power represents a 6 dB increase.
False
The transistor configuration shown below is:
NPN
How many PN junctions does a Unijunction transistor have?
One
Which of the following circuit configurations has the same amount of voltage drop across each of its components?
Parallel
Oscillators use quartz crystals. What effect do these crystals show?
Piezoelectric effect
Prior to connecting an analog voltmeter into a DC circuit, what should be observed?
Polarity
An audio amplifier has severe hum whether CD, AUX, FM or AM RADIO are selected. What is the most likely cause?
Power supply filtering is bad
Regarding PCs, what does "RAM" mean?
Random Access Memory
Total capacitance of capacitors connected in parallel is like:
Resistors connected in series
A voltmeter that converts AC to DC by rectifying the voltage, would be used to measure what types of alternating voltage?
Sinewaves
An AC induction motor requires what to operate?
Slip
A length of coaxial cable, used for computers, radio or television signals, is open at both ends. With An ohmmeter the resistance from the center conductor to the shield is 80 ohms. What does this indicate?
The cable is partially shorted.
Which one of the below will cause a generator to produce DC voltage rather than AC voltage?
The commutator
What is wrong with this circuit?
The diode grounds is wrong
Why should you use a coupling capacitor when troubleshooting with signal injection?
To block the DC signals
Which of the following is an appropriate use for a voltmeter?
To measure difference of potential
The filter configuration shown is commonly called:
a "PI" filter
You would choose an LCD (liquid crystal display) if you needed:
a low-current digital display
Instead of using a direct (x1) probe on an oscilloscope, using an x10 probe has what effect on a circuit test?
all of the above
A dual-trace scope has:
both A&B
Diode semiconductors are marked with a band at the end.
cathode
Each type of coaxial cable is designed with_____________, which is dependent on materials and dimensions used.
characteristic impedance
A negative temperature coefficient thermistor will:
decrease in resistance with heat
which part of a superheterodyne receiver rectifies the RF carrier
detector circuit
An oscilloscope with two vertical inputs, is commonly referred to as a _______ oscilloscope.
dual-trace
