Indicate the false statement. Noise figure is defined as
Athe ratio of the S/N power supplied at the input terminal of a receiver or amplifier to the S/N power supplied to the output or load resistor
Bnoise factor expressed in decibels
Can unwanted form of energy tending to interfere with the proper and easy reception and reproduction of wanted signals
DS/N of an ideal system divided by S/N at the output of the receiver or amplifier under test, both working at the same temperature over the same bandwidth and fed from the same source
#2📘 reviewer_appMedium
In an FM system, if modulation index is doubled by halving the modulating frequency, what will be the effect on the maximum deviation?
ANo effect
BMaximum deviation doubles
CDecreases by 1/2
DIncreases by 1/4
#3📘 reviewer_appMedium
Independent sideband emission type.
AH3E
BR3E
CJ3E
DB8E
#4📘 reviewer_appMedium
In FM, the Carson's Rule states that the bandwidth is equal to twice the sum of the modulating frequency and _______.
Acarrier signal
Bmodulating index
Cfrequency deviation
Dimage frequency
#5📘 reviewer_appMedium
A device, now available in IC form, is useful for direct FM and as one element in the phase-locked loop.
AAFC
BAGC
CVCO
DLPF
#6📘 reviewer_appMedium
________ is a frequency change process, whereby the phase deviation and frequency deviation are multiplied by some fixed constant.
ATranslation
BMultiplication
CDivision
DAddition
#7📘 reviewer_appMedium
The number of voice transmissions that can be packed into a given frequency band for amplitude-compandored single-sideband systems over conventional FM-phone systems.
A2
B8
C16
D4
#8📘 reviewer_appMedium
The transistor with the lowest noise figure in the microwave region is a(n)
AMOSFET
BDual-gate MOSFET
CJFET
DMESFET
#9📘 reviewer_appMedium
In the phasing method of SSB generation, one sideband is cancelled due out to
Aphase shift
Bsharp selectivity
Ccarrier suppression
Dphase inversion
#10📘 reviewer_appMedium
It is a high-performance microwave receiver required at the input stage of the RF section to optimize their noise figure.
Ahigh-power amplifier
Blow-noise amplifier
Cbuffer amplifier
Dlocal oscillator
#11📘 reviewer_appMedium
It is a multipexing method that uses double-sideband suppressed-carrier transmission to combine two information sources into a single composite waveform
AQM
BWDM
CTDM
DFDM
#12📘 reviewer_appMedium
The antenna current is doubled when the modulation index is doubled in ______ AM system
AA5C
BA3J
CA3
DA3H
#13📘 reviewer_appMedium
The low-pass filter in a phase-locked loop is also called
AVCO loop
Bloop filter
Ccontrol voltage filter
Dphase detector
#14📘 reviewer_appMedium
In PM, carrier frequency deviation is not proportional to:
Amodulating signal amplitude
Bcarrier amplitude and frequency
Cmodulating signal frequency
Dmodulator phase shift
#15📘 reviewer_appMedium
To compensate for increases in carrier frequency deviation with an increase in modulating signal frequency, what circuit is used between the modulating signal and the phase modulator?
Alow-pass filter
Bhigh-pass filter
Cphase shifter
Dbandpass filter
#16📘 reviewer_appMedium
It is the worst-case modulation index and is equal to the maximum peak frequency deviation divided by the maximum modulating-signal frequency
Apeak phase deviation
Bfrequency deviation
Cdeviation ratio
Dsignal-to-noise ratio
#17📘 reviewer_appMedium
With stereo transmission, the maximum frequency deviation is
A75 kHz
B15 kHz
C25 kHz
D3 kHz
#18📘 reviewer_appMedium
The maximum frequency deviation for two-way transmitters is typically
A25 kHz
B5 kHz
C75 kHz
D3 kHz
#19📘 reviewer_appMedium
In the phasing method of SSB generation, one sideband is canceled out due to
Aphase shifting
Bsharp selectivity
Ccarrier suppression
Dphase inversion
#20📘 reviewer_appMedium
A double-sideband phone signal can be generated by
Afeeding a phase-modulated signal into a low-pass filter
Bmodulating the plate voltage of a class-C amplifier
