155. The level range of harmonic analyzer using crystal filter is from
A. ?90 dB to 32 dB
B. 20 dB to 40 dB
C. 40 dB to 90 dB
D. 90 dB to 180 dB

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156. Compared to an absorption wavemeter, a reaction wavemeter
A. is more accurate
B. absorbs more power from the signal
C. absorbs less power from the signal
D. has additional resonance frequency indication

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157. A wave guide acts as a
A. low pass filter
B. high pass filter
C. band pass filter
D. band stop filter

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158. The instrument used for frequency measurement in waveguides is
A. balometer
B. cavity resonator
C. galiometer
D. klystron

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159. Which of the following meters is suitable for radio frequency measurement?
A. Electrical resonance frequency meter
B. heterodyne frequency meter
C. Weston frequency meter
D. none of these

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160. A dynamometer type wattmeter responds to the
A. average value of active power
B. average value at reactive power
C. peak value at active power
D. peak value at reactive power

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161. A transfer instrument employed in the standardization of a polar type a.c potentiometer is
A. an electrostatic instrument
B. a thermal instrument
C. a dynamometer instrument
D. a moving coil instrument

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