Extra-Study/pages/E7C.md

E7C Filters and matching networks: types of networks; types of filters; filter applications; filter characteristics; impedance matching

• E7C01 (D) How are the capacitors and inductors of a low-pass filter Pi-network arranged between the network’s input and output? #card
  • A. Two inductors are in series between the input and output, and a capacitor is connected between the two inductors and ground
  • B. Two capacitors are in series between the input and output, and an inductor is connected between the two capacitors and ground
  • C. An inductor is connected between the input and ground, another inductor is connected between the output and ground, and a capacitor is connected between the input and output
  • D. A capacitor is connected between the input and ground, another capacitor is connected between the output and ground, and an inductor is connected between the input and output
• E7C02 (B) What is the frequency response of a T-network with series capacitors and a shunt inductor? #card
  • A. Low-pass
  • B. High-pass
  • C. Band-pass
  • D. Notch
• E7C03 (A) What is the purpose of adding an inductor to a Pi-network to create a Pi-L-network? #card
  • A. Greater harmonic suppression
  • B. Higher efficiency
  • C. To eliminate one capacitor
  • D. Greater transformation range
• E7C04 (C) How does an impedance-matching circuit transform a complex impedance to a resistive impedance? #card
  • A. It introduces negative resistance to cancel the resistive part of impedance
  • B. It introduces transconductance to cancel the reactive part of impedance
  • C. It cancels the reactive part of the impedance and changes the resistive part to the desired value
  • D. Reactive currents are dissipated in matched resistances
• E7C05 (D) Which filter type has ripple in the passband and a sharp cutoff? #card
  • A. A Butterworth filter
  • B. An active LC filter
  • C. A passive op-amp filter
  • D. A Chebyshev filter
• E7C06 (C) What are the characteristics of an elliptical filter? #card
  • A. Gradual passband rolloff with minimal stop-band ripple
  • B. Extremely flat response over its pass band with gradually rounded stop-band corners
  • C. Extremely sharp cutoff with one or more notches in the stop band
  • D. Gradual passband rolloff with extreme stop-band ripple
• E7C07 (B) Which describes a Pi-L network? #card
  • A. A Phase Inverter Load network
  • B. A Pi-network with an additional output series inductor
  • C. A network with only three discrete parts
  • D. A matching network in which all components are isolated from ground
• E7C08 (B) Which of the following is most frequently used as a band-pass or notch filter in VHF and UHF transceivers? #card
  • A. A Sallen-Key filter
  • B. A helical filter
  • C. A swinging choke filter
  • D. A finite impulse response filter
• E7C09 (D) What is a crystal lattice filter? #card
  • A. A power supply filter made with interlaced quartz crystals
  • B. An audio filter made with four quartz crystals that resonate at 1 kHz intervals
  • C. A filter using lattice-shaped quartz crystals for high-Q performance
  • D. A filter for low-level signals made using quartz crystals
• E7C10 (B) Which of the following filters is used in a 2-meter band repeater duplexer? #card
  • A. A crystal filter
  • B. A cavity filter
  • C. A DSP filter
  • D. An L-C filter
• E7C11 (C) Which of the following measures a filter’s ability to reject signals in adjacent channels? #card
  • A. Passband ripple
  • B. Phase response
  • C. Shape factor
  • D. Noise factor