Selftest (Latihan)
Hal 107-108
12.
Linear power amplifiers are used to
raise the power level of Low
Level AM and SSB
13.
A Mosfet power amplifier is used to increase the power level
of an FM signal.
14.
Linear power amplifier operate
class A,B, and AB
15.
A class A transistor power amplifier has
an efficiency of 50 percent. The output power is 27W. The power dissipated in
the transistor is 5W
16.
Class A amplifier conduct for 360 degrees of a sine wave
input.
17.
True or false. With no input, a class B
amplifier does not conduct. FALSE
18.
Class B RF power amplifiers normally
used a(n) Broadband
19.
A class C amplifier conducts for
approximatly 90 degrees
to 150 degrees of
the input signal.
20.
In a class C amplifier, collector
current flows in the form of positive
pulses.
21. In a class C amplifier, a complete sinusoidal output signal is produced by
a(n) Timed Circuit.
22.
The efficiency of a class C amplifier is
in the range of 60 to 85
23.
The tuned circuit in the collector of a
class C amplifier acts as a filter to eliminate Induced Voltage.
24.
A class C amplifier whose output tuned
circuit resonates at some integer multiple of the input frequency is called
a(n) Flywheel effect.
25.
Frequency multipliers with factors of 2,
3, 4, and 5 are cascaded. The input is 1.5MHz. The output is 120
26.
A class C amplifier has DC supply
voltage of 28 V and an average collector current of 1.8A. The power input
is 4W
Hal 150-151
53. RF amplifiers provide initial RF
Amplifier and Mixer in
a receiver but also add Related
Tune Circuits
54. A low-noise transistor preferred at microwave frequencies is the FET made of Metal Semiconductor
55.
Most of the gain and selectivity in a
superhet is obtained in the IF
Amplifier
56.
The selectivity in an IF amplifier is
usually produced by using tuned
circuit between stages
57.
The bandwidth of a double-tuned
transformer depends upon the degree of Coupling between primary and secondary windings
58.
In a double-tuned circuit, minimum
bandwidth is obtained with under
coupling, maximum bandwidth with critical coupling
and peak output with over or optimum coupling
59.
An IF amplifier that clips the positive
and negative peaks of a signal is called a(n) limiter.
60.
Clipping occurs in an amplifier because
the transistor is driven by a high-level signal into Single transistor stage.
61.
The gain of a bipolar class A amplifier
can be varied by changing the positive
peaks and negative peaks.
62.
The overall RF-IF gain of a receiver is
approximately 89
63.
Using the amplitude of the incoming
signal to control the gain of the receiver is known as AGC Voltage gen.
64.
AGC circuits vary the gain of the IF
65.
The DC AGC Voltage is derived from
a(n) AGC circuit
connected to the demodulator or
IF output.
66.
Reverse AGC is where a signal amplitude
increase causes a(n) AGC Voltage
in the IF amplifier collector current.
67.
Forward AGC uses a signal amplitude
increase to positive voltage
the collector current,which decreases the IF amplifier gain.
68.
The AGC of a differential amplifier is
produced by controlling the current produced by the Constant Current
Source
69. In dual-gate MOSFET IF amplifier, the dc AGC Voltage is applied to
the R1 to gate 2.
70.
Another name for AGC in an AM receiver
is Dual Gate MOSFET.
71.
In an AM receiver, the AGC voltage is
derived from the IF Signal.
72.
Large input signals cause the gain of a
receiver to be reduced by
the AGC.
73.
An AFC circuit corrects for frequency
drift in the feedback control
74.
The AFC DC control voltage is derived
from the output of the
demodulator circuit in a receiver.
75.
A(n) Demodulator is used in an AFC circuit to vary the LO
frequency.
76.
A circuit that blocks the audio until a
signal is received is called a(n) squelch
77.
Two types of signals used to operate the
squelch circuit are audiotone
and audiosignal.
78.
In a CTCS system, a low-frequency frequency tone is used to
trigger the squelch
79.
A BFO is required to receive CWCode and SSB
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