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150 Cards in this Set
- Front
- Back
1] Structurally, what are the two main categories of
semiconductor diodes? a} Junction and point contact. b} Electrolytic and junction. c} Electrolytic and point contact. d} Vacuum and point contact. |
a} Junction and point contact.
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2] What are the two primary classifications of Zener diodes?
a} Hot carrier and tunnel. b} Varactor and rectifying. c} Voltage regulator and voltage reference. d} Forward and reversed biased. |
c} Voltage regulator and voltage reference.
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3] What is the principal characteristic of a Zener diode?
a} A constant current under conditions of varying voltage. b} A constant voltage under conditions of varying current. c} A negative resistance region. d} An internal capacitance that varies with the applied voltage. |
b} A constant voltage under conditions of varying current.
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4] What is the range of voltage ratings available in Zener
diodes? a} 2.4 volts to 200 volts. b} 1.2 volts to 7 volts. c} 3 volts to 2000 volts. d} 1.2 volts to 5.6 volts. |
a} 2.4 volts to 200 volts.
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5] What is the principal characteristic of a tunnel diode?
a} A high forward resistance. b} A very high PIV(peak inverse voltage). c} A negative resistance region. d} A high forward current rating. |
c} A negative resistance region.
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6] What special type of diode is capable of both amplification
and oscillation? a} Point contact diodes. b} Zener diodes. c} Tunnel diodes. d} Junction diodes. |
c} Tunnel diodes.
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7] What type of semiconductor diode varies its internal
capacitance as the voltage applied to its terminals varies? a} A varactor diode. b} A tunnel diode. c} A silicon-controlled rectifier. d} A Zener diode. |
a} A varactor diode.
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8] What is the principal characteristic of a varactor diode?
a} It has a constant voltage under conditions of varying current. b} Its internal capacitance varies with the applied voltage. c} It has a negative resistance region. d} It has a very high PIV(peak inverse voltage). |
b} Its internal capacitance varies with the applied voltage.
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9] What is a common use of a varactor diode?
a} As a constant current source. b} As a constant voltage source. c} As a voltage controlled inductance. d} As a voltage controlled capacitance. |
d} As a voltage controlled capacitance.
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10] What is a common use of a hot-carrier diode?
a} As balanced inputs in SSB generation. b} As a variable capacitance in an automatic frequency control circuit. c} As a constant voltage reference in a power supply. d} As VHF and UHF mixers and detectors. |
d} As VHF and UHF mixers and detectors.
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11] What limits the maximum forward current in a junction
diode? a} The peak inverse voltage(PIV). b} The junction temperature. c} The forward voltage. d} The back EMF. |
b} The junction temperature.
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12] How are junction diodes rated?
a} Maximum forward current and capacitance. b} Maximum reverse current and PIV(peak inverse voltage). c} Maximum reverse current and capacitance. d} Maximum forward current and PIV(peak inverse voltage). |
d} Maximum forward current and PIV(peak inverse voltage).
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13] What is a common use for point contact diodes?
a} As a constant current source. b} As a constant voltage source. c} As an RF detector. d} As a high voltage rectifier. |
c} As an RF detector.
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14] What type of diode is made of a metal whisker touching a
very small semiconductor die? a} Zener diode. b} Varactor diode. c} Junction diode. d} Point contact diode. |
d} Point contact diode.
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15] What is one common use for PIN diodes?
a} As a constant current source. b} As a constant voltage source. c} As an RF switch. d} As a high voltage rectifier. |
c} As an RF switch.
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16] What special type of diode is often used in RF switches,
attenuators, and various types of phase shifting devices? a} Tunnel diodes. b} Varactor diodes. c} PIN diodes. d} Junction diodes. |
c} PIN diodes.
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17] What are the three terminals of a bipolar transistor?
a} Cathode, plate and grid. b} Base, collector and emitter. c} Gate, source and sink. d} Input, output and ground. |
b} Base, collector and emitter.
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18] What is the meaning of the term alpha with regard to
bipolar transistors? a} The change of collector current with respect to base current. b} The change of base current with respect to collector current. c} The change of collector current with respect to emitter current. d} The change of collector current with respect to gate current. |
c} The change of collector current with respect to emitter
current. |
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19] What is the term used to express the ratio of change in DC
collector current to a change in emitter current in a bipolar transistor? a} Gamma. b} Epsilon. c} Alpha. d} Beta. |
c} Alpha.
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20] What is the meaning of the term beta with regard to
bipolar transistors? a} The change of collector current with respect to base current. b} The change of base current with respect to emitter current. c} The change of collector current with respect to emitter current. d} The change in base current with respect to gate current. |
a} The change of collector current with respect to base
current. |
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21] What is the term used to express the ratio of change in
the DC collector current to a change in base current in a bipolar transistor? a} Alpha. b} Beta. c} Gamma. d} Delta. |
b} Beta.
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22] What is the meaning of the term alpha cutoff frequency
with regard to bipolar transistors? a} The practical lower frequency limit of a transistor in common emitter configuration. b} The practical upper frequency limit of a transistor in common base configuration. c} The practical lower frequency limit of a transistor in common base configuration. d} The practical upper frequency limit of a transistor in common emitter configuration. |
b} The practical upper frequency limit of a transistor in common
base configuration. |
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23] What is the term used to express that frequency at which
the grounded base current gain has decreased to 0.707 of the gain obtainable at 1 kHz in a bipolar transistor? a} Corner frequency. b} Alpha cutoff frequency. c} Beta cutoff frequency. d} Alpha rejection frequency. |
b} Alpha cutoff frequency.
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24] What is the meaning of the term beta cutoff frequency
with regard to a bipolar transistor? a} That frequency at which the grounded base current gain has decreased to 0.707 of that obtainable at 1 kHz in a transistor. b} That frequency at which the grounded emitter current gain has decreased to 0.707 of that obtainable at 1 kHz in a transistor. c} That frequency at which the grounded collector current gain has decreased to 0.707 of that obtainable at 1 kHz in a transistor. d} That frequency at which the grounded gate current gain has decreased to 0.707 of that obtainable at 1 kHz in a transistor. |
b} That frequency at which the grounded emitter current gain has
decreased to 0.707 of that obtainable at 1 kHz in a transistor. |
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25] What is the meaning of the term transition region with
regard to a transistor? a} An area of low charge density around the P-N junction. b} The area of maximum P-type charge. c} The area of maximum N-type charge. d} The point where wire leads are connected to the P- or N-type material. |
a} An area of low charge density around the P-N junction.
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26] What does it mean for a transistor to be fully saturated?
a} The collector current is at its maximum value. b} The collector current is at its minimum value. c} The transistor's Alpha is at its maximum value. d} The transistor's Beta is at its maximum value. |
a} The collector current is at its maximum value.
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27] What does it mean for a transistor to be cut off?
a} There is no base current. b} The transistor is at its Class A operating point. c} There is no current between emitter and collector. d} There is maximum current between emitter and collector. |
c} There is no current between emitter and collector.
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28] What are the elements of a unijunction transistor?
a} Base 1, base 2, and emitter. b} Gate, cathode, and anode. c} Gate, base 1, and base 2. d} Gate, source, and sink. |
a} Base 1, base 2, and emitter.
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29] For best efficiency and stability, where on the load-line
should a solid-state power amplifier be operated? a} Just below the saturation point. b} Just above the saturation point. c} At the saturation point. d} At 1.414 times the saturation point. |
a} Just below the saturation point.
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30] What two elements widely used in semiconductor devices
exhibit both metallic and non-metallic characteristics? a} Silicon and gold. b} Silicon and germanium. c} Galena and germanium. d} Galena and bismuth. |
b} Silicon and germanium.
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31] What are the three terminals of an SCR?
a} Anode, cathode, and gate. b} Gate, source, and sink. c} Base, collector, and emitter. d} Gate, base 1, and base 2. |
a} Anode, cathode, and gate.
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32] What are the two stable operating conditions of an SCR?
a} Conducting and nonconducting. b} Oscillating and quiescent. c} Forward conducting and reverse conducting. d} NPN conduction and PNP conduction. |
a} Conducting and nonconducting.
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33] When an SCR is in the triggered or on condition, its
electrical characteristics are similar to what other solid-state device (as measured between its cathode and anode)? a} The junction diode. b} The tunnel diode. c} The hot-carrier diode. d} The varactor diode. |
a} The junction diode.
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34] Under what operating condition does an SCR exhibit
electrical characteristics similar to a forward-biased silicon rectifier? a} During a switching transition. b} When it is used as a detector. c} When it is gated "off". d} When it is gated "on". |
d} When it is gated "on".
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35] What is the transistor called which is fabricated as two
complementary SCRs in parallel with a common gate terminal? a} TRIAC. b} Bilateral SCR. c} Unijunction transistor. d} Field effect transistor. |
a} TRIAC.
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36] What are the three terminals of a TRIAC?
a} Emitter, base 1, and base 2. b} Gate, anode 1, and anode 2. c} Base, emitter, and collector. d} Gate, source, and sink. |
b} Gate, anode 1, and anode 2.
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37] What is the normal operating voltage and current for a
light-emitting diode? a} 60 volts and 20 mA. b} 5 volts and 50 mA. c} 1.7 volts and 20 mA. d} 0.7 volts and 60 mA. |
c} 1.7 volts and 20 mA.
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38] What type of bias is required for an LED to produce
luminescence? a} Reverse bias. b} Forward bias. c} Zero bias. d} Inductive bias. |
b} Forward bias.
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39] What is the name of the semiconductor IC that has a
fixed pattern of digital data stored in its memory matrix? a} RAM--Random-Access Memory. b} ROM--Read-Only Memory. c} Register. d} Latch. |
b} ROM--Read-Only Memory.
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40] What colors are available in LEDs?
a} Yellow, blue, red, and brown. b} Red, violet, yellow, and peach. c} Violet, blue, orange, and red. d} Red, green, orange, and yellow. |
d} Red, green, orange, and yellow.
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41] How can a neon lamp be used to check for the presence of
RF? a} A neon lamp will go out in the presence of RF. b} A neon lamp will change color in the presence of RF. c} A neon lamp will light only in the presence of very low frequency (VLF) signal. d} A neon lamp will light in the presence of RF. |
d} A neon lamp will light in the presence of RF.
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42] What would be the bandwidth of a good crystal lattice
band-pass filter for a single-sideband phone emission? a} 6 kHz at -6 dB. b} 2.1 kHz at -6 dB. c} 500 Hz at -6 dB. d} 15 kHz at -6 dB. |
b} 2.1 kHz at -6 dB.
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43] What would be the bandwidth of a good crystal lattice
band-pass filter for a double-sideband phone emission? a} 1 kHz at -6 dB. b} 500 Hz at -6 dB. c} 6 kHz at -6 dB. d} 15 kHz at -6 dB. |
c} 6 kHz at -6 dB.
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44] What is a crystal lattice filter?
a} A power supply filter made with crisscrossed quartz crystals. b} An audio filter made with 4 quartz crystals at 1-kHz intervals. c} A filter with infinitely wide and shallow skirts made using quartz crystals. d} A filter with narrow bandwidth and steep skirts made using quartz crystals. |
d} A filter with narrow bandwidth and steep skirts made using
quartz crystals. |
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45] What technique can be used to construct low cost, high
performance crystal lattice filters? a} Splitting and tumbling. b} Tumbling and grinding. c} Etching and splitting. d} Etching and grinding. |
d} Etching and grinding.
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46] What determines the bandwidth and response shape in a
crystal lattice filter? a} The relative frequencies of the individual crystals. b} The center frequency chosen for the filter. c} The amplitude of the RF stage preceding the filter. d} The amplitude of the signals passing through the filter. |
a} The relative frequencies of the individual crystals.
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47] What is an enhancement-mode FET?
a} An FET with a channel that blocks voltage through the gate. b} An FET with a channel that allows a current when the gate voltage is zero. c} An FET without a channel to hinder current through the gate. d} An FET without a channel; no current occurs with zero gate voltage. |
d} An FET without a channel; no current occurs with zero gate
voltage. |
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48] What is a depletion-mode FET?
a} An FET that has a channel with no gate voltage applied; a current flows with zero gate voltage. b} An FET that has a channel that blocks current when the gate voltage is zero. c} An FET without a channel; no current flows with zero gate voltage. d} An FET without a channel to hinder current through the gate. |
a} An FET that has a channel with no gate voltage applied; a
current flows with zero gate voltage. |
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49] Why do many MOSFET devices have built-in gate-protective
Zener diodes? a} The gate-protective Zener diode provides a voltage reference to provide the correct amount of reverse-bias gate voltage. b} The gate-protective Zener diode protects the substrate from excessive voltages. c} The gate-protective Zener diode keeps the gate voltage within specifications to prevent the device from overheating. d} The gate-protective Zener diode prevents the gate insulation from being punctured by small static charges or excessive voltages. |
d} The gate-protective Zener diode prevents the gate insulation
from being punctured by small static charges or excessive voltages. |
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50] What do the initials CMOS stand for?
a} Common mode oscillating system. b} Complementary mica-oxide silicon. c} Complementary metal-oxide semiconductor. d} Complementary metal-oxide substrate. |
c} Complementary metal-oxide semiconductor.
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51] Why are special precautions necessary in handling FET and
CMOS devices? a} They are susceptible to damage from static charges. b} They have fragile leads that may break off. c} They have micro-welded semiconductor junctions that are susceptible to breakage. d} They are light sensitive. |
a} They are susceptible to damage from static charges.
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52] How does the input impedance of a field-effect transistor
compare with that of a bipolar transistor? a} One cannot compare input impedance without first knowing the supply voltage. b} An FET has low input impedance; a bipolar transistor has high input impedance. c} The input impedance of FETs and bipolar transistors is the same. d} An FET has high input impedance; a bipolar transistor has low input impedance. |
d} An FET has high input impedance; a bipolar transistor has low
input impedance. |
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53] What are the three terminals of a field-effect transistor?
a} Gate 1, gate 2, drain. b} Emitter, base, collector. c} Emitter, base 1, base 2. d} Gate, drain, source. |
d} Gate, drain, source.
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54] What are the two basic types of junction field-effect
transistors? a} N-channel and P-channel. b} High power and low power. c} MOSFET and GaAsFET. d} Silicon FET and germanium FET. |
a} N-channel and P-channel.
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55] What is an operational amplifier?
a} A high-gain, direct-coupled differential amplifier whose characteristics are determined by components external to the amplifier unit. b} A high-gain, direct-coupled audio amplifier whose characteristics are determined by components external to the amplifier unit. c} An amplifier used to increase the average output of frequency modulated signals. d} A program subroutine that calculates the gain of an RF amplifier. |
a} A high-gain, direct-coupled differential amplifier whose
characteristics are determined by components external to the amplifier unit. |
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56] What would be the characteristics of the ideal op-amp?
a} Zero input impedance, infinite output impedance, infinite gain, flat frequency response. b} Infinite input impedance, zero output impedance, infinite gain, flat frequency response. c} Zero input impedance, zero output impedance, infinite gain, flat frequency response. d} Infinite input impedance, infinite output impedance, infinite gain, flat frequency response. |
b} Infinite input impedance, zero output impedance, infinite
gain, flat frequency response. |
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57] What determines the gain of a closed-loop op-amp circuit?
a} The external feedback network. b} The collector-to-base capacitance of the PNP stage. c} The power supply voltage. d} The PNP collector load. |
a} The external feedback network.
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58] What is meant by the term op-amp offset voltage?
a} The output voltage of the op-amp minus its input voltage. b} The difference between the output voltage of the op-amp and the input voltage required in the following stage. c} The potential between the amplifier-input terminals of the op-amp in a closed-loop condition. d} The potential between the amplifier-input terminals of the op-amp in an open-loop condition. |
c} The potential between the amplifier-input terminals of the
op-amp in a closed-loop condition. |
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59] What is the input impedance of a theoretically ideal
op-amp? a} 100 ohms. b} 1000 ohms. c} Very low. d} Very high. |
d} Very high.
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60] What is the output impedance of a theoretically ideal
op-amp? a} Very low. b} Very high. c} 100 ohms. d} 1000 ohms. |
a} Very low.
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61] What is a phase-locked loop circuit?
a} An electronic servo loop consisting of a ratio detector, reactance modulator, and voltage-controlled oscillator. b} An electronic circuit also known as a monostable multivibrator. c} An electronic circuit consisting of a precision push-pull amplifier with a differential input. d} An electronic servo loop consisting of a phase detector, a low-pass filter and voltage-controlled oscillator. |
d} An electronic servo loop consisting of a phase detector, a
low-pass filter and voltage-controlled oscillator. |
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62] What functions are performed by a phase-locked loop?
a} Wideband AF and RF power amplification. b} Comparison of two digital input signals, digital pulse counter. c} Photovoltaic conversion, optical coupling. d} Frequency synthesis, FM demodulation. |
d} Frequency synthesis, FM demodulation.
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63] A circuit compares the output from a voltage-controlled
oscillator and a frequency standard. The difference between the two frequencies produces an error voltage that changes the voltage-controlled oscillator frequency. What is the name of the circuit? a} A doubly balanced mixer. b} A phase-locked loop. c} A differential voltage amplifier. d} A variable frequency oscillator. |
b} A phase-locked loop.
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64] What do the initials TTL stand for?
a} Resistor-transistor logic. b} Transistor-transistor logic. c} Diode-transistor logic. d} Emitter-coupled logic. |
b} Transistor-transistor logic.
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65] What is the recommended power supply voltage for TTL
series integrated circuits? a} 12.00 volts. b} 50.00 volts. c} 5.00 volts. d} 13.60 volts. |
c} 5.00 volts.
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66] What logic state do the inputs of a TTL device assume if
they are left open? a} A high logic state. b} A low logic state. c} The device becomes randomized and will not provide consistent high or low logic states. d} Open inputs on a TTL device are ignored. |
a} A high logic state.
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67] What is the range of input voltages considered to be a
logic high input in a TTL device operating with a 5-volt power supply? a} 2.0 to 5.5 volts. b} 1.5 to 3.0 volts. c} 1.0 to 1.5 volts. d} -5.0 to -2.0 volts. |
a} 2.0 to 5.5 volts.
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68] What is the range of input voltages considered to be a
logic low in a CMOS device operating with an 18-volt power supply? a} -0.8 to 0.0 volts. b} 0.0 to 5.4 volts. c} 0.0 to 0.8 volts. d} -0.8 to 0.4 volts. |
b} 0.0 to 5.4 volts.
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69] Why do circuits containing TTL devices have several bypass
capacitors per printed circuit board? a} To prevent RFI to receivers. b} To keep the switching noise within the circuit, thus eliminating RFI. c} To filter out switching harmonics. d} To prevent switching transients from appearing on the supply line. |
d} To prevent switching transients from appearing on the supply
line. |
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70] What is a CMOS IC?
a} A chip with only P-channel transistors. b} A chip with P-channel and N-channel transistors. c} A chip with only N-channel transistors. d} A chip with only bipolar transistors. |
b} A chip with P-channel and N-channel transistors.
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71] What is one major advantage of CMOS over other devices?
a} Small size. b} Low current consumption. c} Low cost. d} Ease of circuit design. |
b} Low current consumption.
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72] Why do CMOS digital integrated circuits have high immunity
to noise on the input signal or power supply? a} Larger bypass capacitors are used in CMOS circuit design. b} The input switching threshold is about two times the power supply voltage. c} The input switching threshold is about one-half the power supply voltage. d} Input signals are stronger. |
c} The input switching threshold is about one-half the power
supply voltage. |
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73] Signal energy is coupled into a traveling-wave tube at:
a} Collector end of helix. b} Anode end of the helix. c} Cathode end of the helix. d} Focusing coils. |
c} Cathode end of the helix.
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74] Permanent magnetic field that surrounds a traveling-wave
tube (TWT) is intended to: a} Provide a means of coupling. b} Prevent the electron beam from spreading. c} Prevent oscillations. d} Prevent spurious oscillations. |
b} Prevent the electron beam from spreading.
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75] Electromagnetic coils encase a traveling wave tube to:
a} Provide a means of coupling energy. b} Prevent the electron beam from spreading. c} Prevent oscillation. d} Prevent spurious oscillation. |
b} Prevent the electron beam from spreading.
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76] When a doped semiconductor crystal is formed against a
metal conductor, what type of diode is created? a} Schottky diode. b} Tunnel diode. c} Varactor diode. d} Zener diode. |
a} Schottky diode.
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77] What type of diode contains no minority carriers in the
junction region? a} Tunnel diode. b} Varactor diode. c} Zener diode. d} Hot-carrier diode. |
d} Hot-carrier diode.
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78] Mounting an LED facing a photodiode cell in a tiny
light-tight enclosure produces a: a} Seven segment LED. b} Opto-isolator. c} Opto-interrupter. d} Photonic device. |
b} Opto-isolator.
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79] Most bipolar junction transistors have a ____ doped and
____ emitter region compared to the base and collector regions.. a} Heavily, thin. b} Heavily, small. c} Lightly, thin. d} Lightly, small. |
b} Heavily, small.
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80] Most bipolar junction transistors have a ____ doped and
____ base region compared to the emitter and collector regions.. a} Heavily, thin. b} Heavily, small. c} Lightly, thin. d} Lightly, small. |
c} Lightly, thin.
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81] Most bipolar junction transistors have a ____ doped and
____ collector region compared to the base and emitter regions.. a} Heavily, large. b} Heavily, small. c} Lightly, thin. d} Medium, large. |
d} Medium, large.
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82] A common emitter amplifier has:.
a} More current gain than common base or common collector. b} More voltage gain than common base or common collector. c} More power gain than common base or common collector. d} Highest input impedance of the three amplifier configurations. |
c} More power gain than common base or common collector.
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83] A common base amplifier has:.
a} More current gain than common emitter or common collector. b} More voltage gain than common emitter or common collector. c} More power gain than common emitter or common collector. d} Highest input impedance of the three amplifier configurations. |
b} More voltage gain than common emitter or common collector.
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84] An emitter-follower amplifier has:.
a} More current gain than common emitter or common base. b} More voltage gain than common emitter or common base. c} More power gain than common emitter or common base. d} Lowest input impedance of the three amplifier configurations. |
a} More current gain than common emitter or common base.
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85] The JFET's ____________ is the ratio of drain-source
voltage change to gate-source voltage change with drain current constant. a} Amplification factor. b} Dynamic drain resistance. c} Transconductance. d} Pinch-off voltage. |
a} Amplification factor.
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86] The JFET's ____________ is the ratio of drain-source
voltage change to drain current change with the gate-source voltage constant. a} Amplification factor. b} Dynamic drain resistance. c} Transconductance. d} Pinch-off voltage. |
b} Dynamic drain resistance.
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87] The JFET's ____________ is the ratio of drain current
change to gate-source voltage change with drain-source voltage constant. a} Amplification factor. b} Dynamic drain resistance. c} Transconductance. d} Pinch-off voltage. |
c} Transconductance.
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88] When working with JFET's the following terms are used:
amplification factor, dynamic drain resistance, and transconductance. Which of the following relationships is correct? a} dynamic drain resistance = transconductance / amplification factor. b} transconductance = dynamic drain resistance / amplification factor. c} amplification factor = dynamic drain resistance / transconductance. d} amplification factor = dynamic drain resistance * tranconductance. |
d} amplification factor = dynamic drain resistance *
tranconductance. |
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89] What describes a diode junction that is forward biased?
a} It is a high impedance. b} It conducts very little current. c} It is a low impedance. d} It is an open circuit. |
c} It is a low impedance.
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90] What describes a diode junction that is reverse biased?
a} It is a short circuit. b} It conducts a large current. c} It is a low impedance. d} It is a high impedance. |
d} It is a high impedance.
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91] What conditions exist when an NPN transistor is
operating as a Class A amplifier? a} The base-emitter junction is forward biased and the collector-base junction is reverse biased. b} The base-emitter junction and collector-base junction are both forward biased. c} The base-emitter junction and collector-base junction are both reverse biased. d} The base-emitter junction is reverse biased and the collector-base junction is forward biased. |
a} The base-emitter junction is forward biased and the
collector-base junction is reverse biased. |
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92] What conditions exist when a transistor is operating in
saturation? a} The base-emitter junction and collector-base junction are both forward biased. b} The base-emitter junction and collector-base junction are both reverse biased. c} The base-emitter junction is reverse biased and the collector-base junction is forward biased. d} The base-emitter junction is forward biased and the collector-base junction is reverse biased. |
a} The base-emitter junction and collector-base junction are
both forward biased. |
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93] What voltage is required on a silicon NPN switching
transistor's base-emitter junction to cause current between collector and emitter? a} The base must be at least 0.4 volts positive with respect to the emitter. b} The base must be at a negative voltage with respect to the emitter. c} The base must be at least 0.7 volts positive with respect to the emitter. d} The base must be at least 0.7 volts negative with respect to the emitter. |
c} The base must be at least 0.7 volts positive with respect to
the emitter. |
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94] What voltage is required on a silicon PNP switching
transistor's base-emitter junction to cause current between collector and emitter? a} The base must be at least 0.7 volts negative with respect to the emitter. b} The base must be at least 0.4 volts negative with respect to the emitter. c} The base must be positive with respect to the emitter. d} The base must be at least 0.4 volts positive with respect to the emitter. |
a} The base must be at least 0.7 volts negative with respect to
the emitter. |
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95] What semiconductor device controls current between
source and drain due to a variable width channel controlled by a voltage applied between gate and source? a} A bipolar transistor (BJT). b} A field-effect transistor (FET). c} A gate-controlled diode. d} A PNP transistor. |
b} A field-effect transistor (FET).
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96] What are the operating modes for field-effect
transistors? a} Transition and depletion modes. b} Enhancement and transition modes. c} Transition and non-transition modes. d} Depletion and enhancement modes. |
d} Depletion and enhancement modes.
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97] What is an enhancement-mode FET?
a} An FET with a channel that blocks voltage through the gate. b} An FET with a channel that allows a current between source and drain when the gate voltage is zero. c} An FET without a channel to hinder current through the gate. d} An FET without a channel; no current between source and drain with zero gate voltage. |
d} An FET without a channel; no current between source and drain
with zero gate voltage. |
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98] What is a depletion-mode FET?
a} An FET that has a channel with no gate voltage applied; there is current between source and drain when the gate voltage is zero. b} An FET that has a channel that blocks current when the gate voltage is zero. c} An FET without a channel; there is no current from source to drain with zero gate voltage. d} An FET without a channel to hinder current through the gate. |
a} An FET that has a channel with no gate voltage applied; there
is current between source and drain when the gate voltage is zero. |
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99] What is a silicon integrated circuit (IC)?
a} A complex semiconductor device containing within it all the circuit components interconnected on a single chip of silicon. b} A large number of discrete components wired together on a silicon substrate. c} Individual components integrated together on a printed wiring board. d} A circuit of discrete individual silicon components. |
a} A complex semiconductor device containing within it all the
circuit components interconnected on a single chip of silicon. |
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100] What are the advantages of using an LED?
a} Low power consumption and long life. b} High lumens per cm squared and low power consumption. c} High lumens per cm squared and low voltage requirement. d} A current flows when the device is exposed to a light source. |
a} Low power consumption and long life.
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101] What determines the visible color radiated by an LED?
a} The color of a lens in an eyepiece. b} The amount of voltage across the device. c} The amount of current through the device. d} The materials used to construct the device. |
d} The materials used to construct the device.
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102] What level of input voltage is considered a logic low
in a TTL device operating with a 5 volt power supply? a} -2.0 to -5.5 volts. b} 2.0 to 5.5 volts. c} 0.0 to 0.8 volts. d} -0.8 to 0.4 volts. |
c} 0.0 to 0.8 volts.
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103] Where is the external feedback network connected to
control the gain of a closed-loop op-amp circuit? a} From output to inverting input. b} From output to non-inverting input. c} Across the output. d} Across the input. |
a} From output to inverting input.
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104] What is the name of the semiconductor memory IC whose
digital data can be written or read, and whose memory word address can be accessed randomly? a} ROM--Read-Only Memory. b} PROM--Programmable Read-Only Memory. c} RAM--Random-Access Memory. d} EPROM--Electrically Programmable Read-Only Memory. |
c} RAM--Random-Access Memory.
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105] What is the name of the random-accessed semiconductor
memory IC that must be refreshed periodically to maintain reliable data storage in its memory matrix? a} ROM--Read-Only Memory. b} PROM--Programmable Read-Only Memory. c} PRAM--Programmable Random-Access Memory. d} DRAM--Dynamic Random-Access Memory. |
d} DRAM--Dynamic Random-Access Memory.
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106] What would be the bandwidth of a good crystal lattice
band-pass filter for weather facsimile HF (high frequency) reception? a} 1 kHz at -6 dB. b} 500 Hz at -6 dB. c} 6 kHz at -6 dB. d} 15 kHz at -6 dB. |
b} 500 Hz at -6 dB.
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107] The capacitance of a varactor ____ as the ____ bias is
increased. Assume proper bias to use the diode as a varactor. a} Increases, forward. b} Increases, reverse. c} Decreases, forward. d} Decreases, reverse. |
d} Decreases, reverse.
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108] The screen grid was added to vacuum tubes to reduce
____ and draw space-charge electrons from the cathode through the control grid wires. a} Mu. b} Transconductance. c} Plate-impedance values. d} Grid-plate capacitance. |
d} Grid-plate capacitance.
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109] When working with tetrodes, as long as plate-voltage is
greater than screen-grid voltage, what effect on plate current would be noticed if you doubled plate voltage? a} Plate current would be decreased by a factor of 1/2. b} Plate current would be increased by a factor of 2. c} Plate current would barely increase. d} Plate current would be increased by a factor equal to Mu. |
c} Plate current would barely increase.
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110] Which of the following is not an advantage of using
pentodes. a} Usually requires no neutralization in high frequency circuits. b} Higher Mu than triodes or tetrodes. c} Higher secondary emission resulting in greater plate current. d} Better shielding between plate and control grid. |
c} Higher secondary emission resulting in greater plate
current. |
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111] Which of the following is not an advantage of gaseous
tubes. a} Little heat dissipation. b} Carry relatively low currents. c} High efficiency. d} Relatively constant voltage-drop across them. |
b} Carry relatively low currents.
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112] A pulse width modulator IC would most likely be found
in which of the following: a} Ringing choke power supply. b} Solid-state DC to DC converter. c} Crowbar protection circuit. d} Shunt regulator with error-signal amp. |
a} Ringing choke power supply.
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113] An 800 kHz crystal, calibrated at 40 degrees Celsius
and having a temperature coefficient of -30 parts per million per degree Celsius, will resonate at what frequency when operated at 60 degrees Celsius? a} 799.52 kHz. b} 799.40 kHz. c} 800.60 kHz. d} 800.48 kHz. |
a} 799.52 kHz.
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114] An 800 kHz crystal, calibrated at 40 degrees Celsius
and having a temperature coefficient of +30 parts per million per degree Celsius, will resonate at what frequency when operated at 60 degrees C.? a} 799.52 kHz. b} 799.40 kHz. c} 800.60 kHz. d} 800.48 kHz. |
d} 800.48 kHz.
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115] Which of the following does not have a negative
resistance region? a} Dynatron. b} Tunnel diode. c} Unijunction transistor. d} Schottky diode. |
d} Schottky diode.
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116] A phase-locked loop IC could be used in all of the
following applications except: a} Frequency-shift keying (FSK). b} Horizontal sweep AFC. c} Frequency synthesis. d} Phase-shift oscillator. |
d} Phase-shift oscillator.
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117] Which of the following logic gates will provide an
active high out when both inputs are active high? a} AND. b} NAND. c} NOR. d} XOR. |
a} AND.
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118] Which of the following logic gates will provide an
active low out when both inputs are active high? a} AND. b} NAND. c} OR. d} XNOR. |
b} NAND.
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119] Which of the following logic gates will provide an
active high out when any input is active high? a} AND. b} NAND. c} OR. d} NOR. |
c} OR.
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120] Which of the following logic gates will provide an
active low out when any input is active high? a} AND. b} NAND. c} OR. d} NOR. |
d} NOR.
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121] Which of the following logic gates will provide an
active high out only when all inputs are different? a} OR. b} NOR. c} XOR. d} XNOR. |
c} XOR.
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122] Which of the following logic gates will provide an
active low out only when all inputs are different? a} OR. b} NOR. c} XOR. d} XNOR. |
d} XNOR.
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123] Which of the following inputs to a D flip-flop are
considered to be asynchronous? a} D, CLK. b} PRE, CLR. c} D, PRE. d} CLK, CLR. |
b} PRE, CLR.
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124] Which of the following inputs to a J-K flip-flop are
considered to be synchronous? a} J, K. b} PRE, CLR. c} CLK, PRE. d} Q, CLR. |
a} J, K.
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125] An R-S flip-flop is capable of doing all of the
following except:. a} Accept data input into R-S inputs with CLK initiated. b} Accept data input into PRE and CLR inputs without CLK being initiated. c} Refuse to accept synchronous data if asynchronous data is being input at same time. d} Operate in toggle mode with R-S inputs held constant and CLK initiated. |
d} Operate in toggle mode with R-S inputs held constant and CLK
initiated. |
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126] The toggle mode of operation, achieved by applying a
string of CLK pulses, is a normal operation mode for which of the following? . a} D flip-flop. b} R-S flip-flop. c} J-K flip-flop. d} Bistable Multivibrator. |
c} J-K flip-flop.
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127] How many R-S flip-flops would be required to construct
an 8 bit storage register? a} 2. b} 4. c} 8. d} 16. |
c} 8.
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128] How many J-K flip-flops would be required to construct
a MOD 16 ripple counter? a} 2. b} 4. c} 8. d} 16. |
b} 4.
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129] How many D flip-flops would be required to construct a
MOD 16 ring counter? a} 2. b} 4. c} 8. d} 16. |
d} 16.
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130] If an input CLK frequency of 160 kHz is applied to a
four bit ripple counter capable of achieving full count before roll-over, what frequency can you expect to measure at the MSB output? a} 10 kHz. b} 20 kHz. c} 40 kHz. d} 320 kHz. |
a} 10 kHz.
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131] If a CLK frequency of 160 kHz is applied to the
Count-Up input pin of a BCD counting chip, what will be the frequency available at the Carry-Out pin of that same chip? (assume all other inputs are proper). a} 10 kHz. b} 16 kHz. c} 160 kHz. d} 320 kHz. |
b} 16 kHz.
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132] Which of the following are contained in an LCD display?
a} Semi-conductor P-N junctions. b} Light emitting diodes. c} Photovoltaic material. d} Nematic fluid. |
d} Nematic fluid.
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133] Which of the following is not an analog to digital
converter? a} Digital-ramp ADC. b} Successive approximation ADC. c} Flash ADC. d} R/2R ladder ADC. |
d} R/2R ladder ADC.
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134] A -- NOTed OR, bubbled OR, or negative OR -- gate
performs the same logic function as which of the following gates? a} AND. b} NAND. c} XOR. d} XNOR. |
b} NAND.
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135] A -- NOTed AND, bubbled AND, or negative AND -- gate
performs the same logic function as which of the following gates? a} OR. b} NOR. c} XOR. d} XNOR. |
b} NOR.
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136] Which of the following logic functions can not be
duplicated when using a single IC containing quad 2-input NAND gates? (you can use all available gates contained in the one IC mentioned). a} AND. b} XOR. c} OR. d} NOR. |
b} XOR.
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137] Which of the following logic functions would require
the fewest number of NOR gates to duplicate? a} AND. b} NAND. c} XOR. d} XNOR. |
a} AND.
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138] Which of the following applications usually requires a
parallel-to-serial conversion of data? a} Transfer a byte of data from a microcomputer's RAM to its CPU. b} Transfer a byte of data from a microcomputer's ROM to its CPU. c} Transfer a byte of data from a microcomputer's RAM to its monitor. d} Transfer a byte of data from a microcomputer's RAM to its ALU. |
c} Transfer a byte of data from a microcomputer's RAM to its
monitor. |
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139] Which of the following codes has gained the widest
acceptance in modern times for exchange of data from one computer to another? a} ASCII code. b} Baudot code. c} Morse code. d} Gray code. |
a} ASCII code.
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140] Which of the following op-amp circuits is operated
open-loop? a} Comparator. b} Non-inverting amp. c} Inverting amp. d} Active filter. |
a} Comparator.
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141] Slew rate of an op-amp means:
a} Output voltage change per nanosecond. b} Output voltage change per microsecond. c} Output voltage change per millisecond. d} Output voltage change per second. |
b} Output voltage change per microsecond.
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142] RF chokes are sometimes constructed of universal wound
pies to: a} Lower impedance to a relatively wide band of frequencies for which it was manufactured. b} Increase impedance to a relatively narrow band of frequencies for which it was manufactured. c} Increase the end-to-end distributed capacitance. d} Decrease the end-to-end distributed capacitance. |
d} Decrease the end-to-end distributed capacitance.
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143] Which of the following types of microphones is least
likely to be used in broadcast applications? a} Condenser microphone. b} Crystal microphone. c} Dynamic microphone. d} Magnetic microphone. |
b} Crystal microphone.
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144] How many individual memory cells would be contained in
a memory IC that has 4 data bus input/output pins and 4 address pins for connection to the address bus? a} 8 memory cells. b} 16 memory cells. c} 32 memory cells. d} 64 memory cells. |
d} 64 memory cells.
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145] When referring to digital IC's, which of the following
contains between 100 to 9999 gates? a} MSI (medium-scale integration). b} LSI (large-scale integration). c} VLSI (very large-scale integration). d} ULSI (ultra large-scale integration). |
b} LSI (large-scale integration).
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146] Which of the following devices acts as two SCR's
connected back to back, but facing in opposite directions and sharing a common gate? a} JFET. b} Dual-gate MOSFET. c} DIAC. d} TRIAC. |
d} TRIAC.
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147] Which of the following devices is normally used to
regulate the amount of AC current flowing to a load from approximately 0 degrees to no more than 180 degrees of the input signal? a} DIAC. b} SCR. c} TRIAC. d} Class A BJT amp. |
b} SCR.
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148] Which of the following devices is normally used to
regulate the amount of AC current flowing to a load from approximately 0 degrees to 360 degrees of the input signal? a} DIAC. b} SCR. c} TRIAC. d} Class B BJT amp. |
c} TRIAC.
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149] Which of the following devices produces the least
amount of noise when used as a part of a mixer stage in a superheterodyne receiver? a} Bipolar-junction transistor. b} Dual-gate MOSFET. c} Duo-triode vacuum tube. d} P-N junction diode. |
b} Dual-gate MOSFET.
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150] Which of the following devices is used principally as
VHF and UHF parasitic suppressers? a} Ferrite bead. b} Balun. c} Autotransformer. d} Swinging choke. |
a} Ferrite bead.
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