US_EXTRA
Amateur Extra - Components and circuit devices
Components and circuit devices groups the E6 section questions for focused review and easier weak-point tracking.
68
Questions
9
Sibling Topics
- Pool
- Amateur Extra
- Questions
- 68
- Topic
- Components and circuit devices
- Region
- US
Read the condition in the stem before comparing key terms in the options.
Study rules, calculations, and equipment questions as separate patterns.
After this topic, return to the full pool for mixed practice.
Topic Study Guide
This topic covers components and circuit devices (E6) for the Amateur Extra exam, focusing on semiconductor materials, specialized diodes, digital logic, inductor cores, and optoelectronic devices.
High-Yield Checks
- Gallium arsenide (GaAs) characteristics: Used in microwave and UHF semiconductor devices and MMICs due to high electron mobility.
- Functions of specialized diodes: Zener diodes provide constant voltage, while varactor diodes act as voltage-controlled capacitors.
- Digital logic and ICs: CMOS has the lowest power consumption; comparators change output state when the input crosses the threshold.
- Inductors and core properties: Permeability determines inductance, and toroidal cores confine magnetic fields within the material.
Trap Patterns
- Confusing diode uses and symbols: Easily mixing up Zener (voltage regulation) with Varactor (capacitance), or misidentifying the Schottky diode symbol.
- Misidentifying logic gate symbols: Overlooking the small inversion circle at the output (e.g., NOT or NAND gates) or confusing the shapes of NAND and NOR.
- Mixing up physical concepts: Confusing permeability (inductors) with permittivity (capacitors), or misunderstanding which particles absorb energy in the photovoltaic effect (electrons, not photons).
Review Steps
- Group and memorize the circuit symbols in the E6 figures, especially MOSFETs, specialized diodes, and logic gates.
- Compare and memorize the applicable frequency bands and core advantages of different semiconductor materials (e.g., Silicon vs. GaAs).
- Review basic concepts of digital logic circuits, clarifying the power and speed characteristics of logic families like CMOS and TTL.
- Understand component traits through practical applications, such as why MMICs use 50-ohm impedance and microstrip, and the combined benefits of SMT.
Quick Checks
- What is the typical base-to-emitter voltage of a biased-on silicon NPN transistor?
- Which digital logic family has the lowest power consumption?
- What is the primary advantage of using a toroidal core in an inductor?
- What is the most common input and output impedance of MMICs?
Questions in This Topic
Choose Practice ModeE6A01In what application is gallium arsenide used as a semiconductor material?E6A02Which of the following semiconductor materials contains excess free electrons?E6A03Why does a PN-junction diode not conduct current when reverse biased?E6A04What is the name given to an impurity atom that adds holes to a semiconductor crystal structure?E6A05How does DC input impedance at the gate of a field-effect transistor (FET) compare with that of a bipolar transistor?E6A06What is the beta of a bipolar junction transistor?E6A07Which of the following indicates that a silicon NPN junction transistor is biased on?E6A08What is the term for the frequency at which the grounded-base current gain of a bipolar junction transistor has decreased to 0.7 of the gain obtainable at 1 kHz?E6A09What is a depletion-mode field-effect transistor (FET)?E6A10In Figure E6-1, which is the schematic symbol for an N-channel dual-gate MOSFET?E6A11In Figure E6-1, which is the schematic symbol for a P-channel junction FET?E6A12What is the purpose of connecting Zener diodes between a MOSFET gate and its source or drain?E6B01What is the most useful characteristic of a Zener diode?E6B02Which characteristic of a Schottky diode makes it a better choice than a silicon junction diode for use as a power supply rectifier?E6B03What property of an LED's semiconductor material determines its forward voltage drop?E6B04What type of semiconductor device is designed for use as a voltage-controlled capacitor?E6B05What characteristic of a PIN diode makes it useful as an RF switch?E6B06Which of the following is a common use of a Schottky diode?E6B07What causes a junction diode to fail from excessive current?E6B08Which of the following is a Schottky barrier diode?E6B09What is a common use for point-contact diodes?E6B10In Figure E6-2, which is the schematic symbol for a Schottky diode?E6B11What is used to control the attenuation of RF signals by a PIN diode?E6C01What is the function of hysteresis in a comparator?E6C02What happens when the level of a comparator’s input signal crosses the threshold voltage?E6C03What is tri-state logic?E6C04Which of the following is an advantage of BiCMOS logic?E6C05Which of the following digital logic families has the lowest power consumption?E6C06Why do CMOS digital integrated circuits have high immunity to noise on the input signal or power supply?E6C07What best describes a pull-up or pull-down resistor?E6C08In Figure E6-3, which is the schematic symbol for a NAND gate?E6C09What is used to design the configuration of a field-programmable gate array (FPGA)?E6C10In Figure E6-3, which is the schematic symbol for a NOR gate?E6C11In Figure E6-3, which is the schematic symbol for the NOT operation (inversion)?E6D01What is piezoelectricity?E6D02What is the equivalent circuit of a quartz crystal?E6D03Which of the following is an aspect of the piezoelectric effect?E6D04Why are cores of inductors and transformers sometimes constructed of thin layers?E6D05How do ferrite and powdered iron compare for use in an inductor core?E6D06What core material property determines the inductance of an inductor?E6D08Which of the following materials has the highest temperature stability of its magnetic characteristics?E6D09What devices are commonly used as VHF and UHF parasitic suppressors at the input and output terminals of a transistor HF amplifier?E6D10What is a primary advantage of using a toroidal core instead of a solenoidal core in an inductor?E6D11Which type of core material decreases inductance when inserted into a coil?E6D12What causes inductor saturation?E6E01Why is gallium arsenide (GaAs) useful for semiconductor devices operating at UHF and higher frequencies?E6E02Which of the following device packages is a through-hole type?E6E03Which of the following materials supports the highest frequency of operation when used in MMICs?E6E04Which is the most common input and output impedance of MMICs?E6E05Which of the following noise figure values is typical of a low-noise UHF preamplifier?E6E06What characteristics of MMICs make them a popular choice for VHF through microwave circuits?E6E07What type of transmission line is often used for connections to MMICs?E6E08How is power supplied to the most common type of MMIC?E6E09Which of the following component package types have the least parasitic effects at frequencies above the HF range?E6E10What advantage does surface-mount technology offer at RF compared to using through-hole components?E6E11What is a characteristic of DIP packaging used for integrated circuits?E6E12Why are DIP through-hole package ICs not typically used at UHF and higher frequencies?E6F01What absorbs the energy from light falling on a photovoltaic cell?E6F02What happens to photoconductive material when light shines on it?E6F03What is the most common configuration of an optoisolator or optocoupler?E6F04What is the photovoltaic effect?E6F05Which of the following describes an optical shaft encoder?E6F06Which of these materials is most commonly used to create photoconductive devices?E6F07What is a solid-state relay?E6F08Why are optoisolators often used in conjunction with solid-state circuits that control 120 VAC circuits?E6F09What is the efficiency of a photovoltaic cell?E6F10What is the most common material used in power-generating photovoltaic cells?E6F11What is the approximate open-circuit voltage produced by a fully illuminated silicon photovoltaic cell?