Description : What is the result of an impedance mismatch between a receiver or transmitter and its transmission line or antenna?
Last Answer : High vswr, which equates to poor reception or a loss of power output.
Description : The presence of standing waves on a transmission line is the result of A. a high level of attenuation on the line. B. terminating the line by a resistive load equal in value to the surge impedance ... input power to below its critical level. D. an impedance mismatch between the load and the line.
Last Answer : D. an impedance mismatch between the load and the line.
Description : What device is used to produce a gradual change in impedance at the end of a waveguide?
Last Answer : Horn.
Description : What is the result of an abrupt change in the size, shape, or dielectric of a waveguide?
Last Answer : Reflections.
Description : Standing waves occurs due to a) Impedance match b) Impedance mismatch c) Reflection d) Transmission
Last Answer : b) Impedance mismatch
Description : In some cases, it’s also hard to map an object to XML (e.g., an object graph with cyclic references) because there’s actually an impedance mismatch between an object model and an XML model. a) True b) False
Last Answer : True
Description : A waveguide may also be terminated in a resistive load that is matched to the characteristic impedance of the waveguide. The resistive load is most often called a _____
Last Answer : Dummy resistor
Last Answer : Standing-wave ratio (swr).
Description : Which of the following statement(s) is/are true concerning the pathophysiology of gas exchange? a. Hypoventilation in relation to perfusion can result in an oxygen saturation of less than 100% ... does not occur under normal circumstances d. The normal arterial oxygen saturation should be 100%
Last Answer : Answer: a, b Under normal conditions, red blood cells in the pulmonary capillaries become fully saturated and oxygen dissolves in plasma resulting in blood PO2 of 100 and O2 saturation of 100%. This ... the fact that normal arterial PO2 is 90-100 mm Hg and the normal O2 saturation is 98%
Description : What is the most likely cause of losses in waveguide systems?
Last Answer : Improperly connected joints or damaged inner surface.
Description : What is the most common type of waveguide joint?
Last Answer : Choke joint.
Description : A waveguide bend must have what minimum radius?
Last Answer : Greater than 2 wavelengths.
Description : When a waveguide is terminated in a resistive load, the load must be matched to what property of the waveguide?
Last Answer : . Characteristic impedance.
Description : Loose or inefficient coupling of energy into or out of a waveguide can be accomplished by the use of what method?
Last Answer : Slots and apertures.
Description : What determines the frequency, bandwidth, and power handling capability of a waveguide probe?
Last Answer : Size and shape
Description : Which subscript, in circular waveguide classification, indicates the number of full-wave patterns around the circumference?
Last Answer : First.
Description : The electric field is perpendicular to the "a" dimension of a waveguide in what mode?
Last Answer : TE.
Description : How is the cutoff wavelength of a circular waveguide figured?
Last Answer : 1.71 times the diameter.
Description : What field configuration is easiest to produce in a given waveguide?
Last Answer : . Dominant mode
Description : What term is used to identify the forward progress velocity of wavefronts in a waveguide?
Last Answer : Group velocity.
Description : incidence and reflection that are perpendicular to the waveguide walls?
Last Answer : Cutoff frequency.
Description : Assuming the wall of a waveguide is perfectly flat, what is the angular relationship between the angle of incidence and the angle of reflection
Last Answer : The angles are equal.
Description : When a wavefront is radiated into a waveguide, what happens to the portions of the wavefront that do not satisfy the boundary conditions?
Last Answer : Decrease to zero.
Description : What interaction causes energy to travel down a waveguide?
Last Answer : The interaction of the electric and magnetic fields.
Description : When the frequency is decreased so that two quarter wavelengths are longer than the "a" (wide) dimension of the waveguide, what will happen?
Last Answer : Energy will no longer pass through the waveguide.
Description : What happens to the bus bar dimensions of the waveguide when the frequency is increased?
Last Answer : The bus bar becomes wider.
Description : The frequency range of a waveguide is determined by what dimensions?
Last Answer : . The "a" dimension.
Description : The large surface area of a waveguide greatly reduces what type of loss that is common in two-wire and coaxial lines?
Last Answer : Copper loss.
Description : The folded waveguide in a bwo serves the same purpose as what component in a twt?
Last Answer : Helix.
Description : How does a waveguide-type lens focus spherical wavefront microwave energy?
Last Answer : Some wavefronts are accelerated so that all wavefronts exit the lens at the same time
Description : Which dispersion mechanism (material or waveguide) is a function of the size of the fiber's core relative to the wavelength of operation?
Last Answer : Waveguide dispersion.
Description : What components form the input-signal-developing impedance for the amplifier?
Last Answer : C2 and the secondary of T1.
Description : If the output impedance of an amplifier circuit is decreased, what is the effect on the gain?
Last Answer : The gain decreases.
Description : If the input-signal-developing impedance of an amplifier is increased, what is the effect on the gain?
Last Answer : The gain increases.
Description : In a parallel-resonant circuit, what is the relationship between impedance and current?
Last Answer : Maximum impedance, minimum current.
Description : In a series-RLC circuit, what is the condition of the circuit if there is high impedance, low current, and low reactance voltages
Last Answer : Nonresonant (circuit is either above or below resonance)
Description : . In an "ideal" resonant circuit, what is the relationship between impedance and current?
Last Answer : Impedance low Current high.
Description : When compared to the JFET, what is the input impedance of the MOSFET?
Last Answer : The MOSFET has a higher input impedance.
Description : If the impedance of the choke is increased, will the ripple amplitude increase or decrease?
Last Answer : Decrease.
Description : The actions of the tr and atr circuits depend on the impedance characteristics of what length of transmission line?
Last Answer : Quarter-wavelength section
Description : What do impedance-angle meters and vector bridges have in common?
Last Answer : Both measure phase angle and magnitude in determining impedance.
Description : What is the range of the characteristic impedance of lines used in actual practice?
Last Answer : Between 50 and 600 ohms.
Description : What symbol is used to designate the characteristic impedance of a line, and what two variables does it compare?
Last Answer : Z0 and it is the ratio of E to I at every point along the line.
Description : What is the impedance of a crystal at its resonant frequency when it is used in the series mode?
Last Answer : Minimum.
Description : What is the impedance of a crystal at its resonant frequency when it is used in the parallel mode?
Last Answer : Maximum
Description : Which preamplifier design (high-impedance or transimpedance) provides improvements in bandwidth and greater dynamic range with some degradation in sensitivity from an increase in noise?
Last Answer : Transimpedance.
Description : What happens to the impedance of interelectrode capacitance as frequency increases?
Last Answer : Impedance decreases.
Description : In swept-frequency testing the impedance of a transmission line, what electrical characteristic is actually being measured?
Last Answer : Swr on the transmission line.
Description : What is the difference between calculating impedance in a series ac circuit and in a parallel ac circuit?
Last Answer : In a series circuit impedance is calculated from the values of resistance and reactance. In a parallel circuit, the values of resistive current and reactive current must be used to calculate total impedance.
Description : What type of impedance does the tank circuit have above resonance?
Last Answer : Inductive.