% FILENAME = N25.TXT
% Receiver Block Diagrams
% Release version 3, October 2001
% Q 15 and 19 changed 6 Mar 2012

%Question: 1
#16.1 In the block diagram of the receiver shown, the "RF amplifier": 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15>

decreases random fluctuation noise 

is a restoring filter amplifier 

increases the incoming signal level 

changes the signal frequency 

% ans 3 


%Question: 2
#16.2 In the block diagram of the receiver shown, the "mixer": 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15>

combines signals at two different frequencies to produce one at an intermediate frequency 

combines sidebands to produce a stronger signal 

discriminates against SSB and AM signals 

inserts a carrier wave to produce a true FM signal 

% ans 1 


%Question: 3
#16.3 In the block diagram of the receiver shown, the output frequency of the 
"oscillator" is: 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15>

the same as that of the incoming received signal 

the same as that of the IF frequency 

different from both the incoming signal and IF frequencies 

at a low audio frequency 

% ans 3  

%Question: 4
#16.4 In the block diagram of the receiver shown, the "filter" rejects: 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15>

AM and RTTY signals 

unwanted mixer outputs 

noise bursts 

broadcast band signals 

% ans 2  

%Question: 5
#16.5 In the block diagram of the receiver shown, the "IF amplifier" is an: 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15 >

isolation frequency amplifier 

intelligence frequency amplifier 

indeterminate frequency amplifier 

intermediate frequency amplifier 

% ans 4  

%Question: 6
#16.6 In the block diagram of the receiver shown, the "product detector": 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15>

produces an 800 Hz beat note 

separates CW and SSB signals 

rejects AM signals 

translates signals to audio frequencies 

% ans 4  

%Question: 7
#16.7 In the block diagram of the receiver shown, the "AF amplifier": 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15>

rejects AM and RTTY signals 

amplifies audio frequency signals 

has a very narrow passband 

restores ambiance to the audio 

% ans 2  

%Question: 8
#16.8 In the block diagram of the receiver shown, the "BFO" stands for: 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15>

bad frequency obscurer 

basic frequency oscillator 

beat frequency oscillator 

band filter oscillator 

% ans 3  

%Question: 9
#16.9 In the block diagram of the receiver shown, most of the receiver gain is in the: 
<img src = "ssbrx.gif" align = center width = 600 height = 161> 
<totallines = 15>

RF amplifier 

IF amplifier 

AF amplifier 

mixer 

% ans 2  

%Question: 10
#16.10 In the block diagram of the receiver shown, the "RF amplifier": 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

decreases random fluctuation noise 

masks strong noise 

should produce little internal noise 

changes the signal frequency 

% ans 3  

%Question: 11
#16.11 In the block diagram of the receiver shown, the "mixer": 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

changes the signal frequency 

rejects SSB and CW signals 

protects against receiver overload 

limits the noise on the signal 

% ans 1 

%Question: 12
#16.12 In the receiver shown, when receiving a signal, the output frequency of the "oscillator" is: 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16 >

the same as that of the signal 

the same as that of the IF amplifier 

of constant amplitude and frequency 

passed through the following filter 

% ans 3  

%Question: 13
#16.13 In the block diagram of the receiver shown, the "limiter": 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

limits the signal to a constant amplitude 

rejects SSB and CW signals 

limits the frequency shift of the signal 

limits the phase shift of the signal 

% ans 1  

%Question: 14
#16.14 In the block diagram of the receiver shown, the "frequency demodulator" 
could be implemented with a: 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

product detector 

phase-locked loop 

full-wave rectifier 

low-pass filter 

% ans 2  

%Question: 15
#16.15 In the block diagram of the receiver shown, the "AF amplifier": 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

amplifies stereo signals 

amplifies speech frequencies 

is an all frequency amplifier 

must be fitted with a tone control 

% ans 2  

%Question: 16 
#16.16 In this receiver, an audio frequency gain control 
would be associated with the block labelled: 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

AF amplifier 

frequency demodulator 

speaker, phones 

IF amplifier 

% ans 1  

%Question: 17
#16.17 In the block diagram of the receiver shown, the selectivity would be set by the: 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

AF amplifier 

mixer 

limiter 

filter 

% ans 4  

%Question: 18
#16.18 In the FM communications receiver shown in the block diagram, the "filter" 
bandwidth is typically: 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

3 kHz 

10 kHz 

64 kHz 

128 kHz 

% ans 2  

%Question: 19
#16.19 In the block diagram of the receiver shown, an automatic gain 
control (AGC) circuit would be associated with the: 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16> 

Speaker 

IF amplifier 

RF filter 

Oscillator

% ans 2  

%Question: 20
#16.20 In the block diagram of the receiver shown, the waveform produced by the 
"oscillator" would ideally be a: 
<img src = "fmrx.gif" align = center width = 600 height = 151> 
<totallines = 16>

square wave 

pulsed wave 

sinewave 

hybrid frequency wave 

% ans 3  


