% FILENAME = N15.TXT
% HF Station Arrangement 
% Release version 3, October 2001

%QUESTION: 1
#15.1 In the block diagram shown, the "linear amplifier" is: 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

an amplifier to remove distortion in signals from the transceiver 

an optional amplifier to be switched in when higher power is required 

an amplifier with all components arranged in-line 

a push-pull amplifier to cancel second harmonic distortion 

% ans 2 

%QUESTION: 2
#15.2 In the block diagram shown, the additional signal path above the 
"linear amplifier" block indicates that: 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

some power is passed around the linear amplifier for stability 

"feed-forward" correction is being used to increase linearity 

the linear amplifier input and output terminals may be short-circuited 

the linear amplifier may be optionally switched out of circuit to reduce output power 

% ans 4 

%QUESTION: 3
#15.3 In the block diagram shown, the "low pass filter" must be rated to: 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

carry the full power output from the station 

filter out higher-frequency modulation components for maximum intelligibility 

filter out high-amplitude sideband components 

emphasise low-speed Morse code output  

% ans 1 

%QUESTION: 4
#15.4 In the block diagram shown, the "SWR bridge" is a: 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

switched wave rectifier for monitoring power output 

static wave reducer to minimize static electricity from the antenna 

device to monitor the standing-wave-ratio on the antenna feedline 

short wave rectifier to protect against lightning strikes 

% ans 3 

%QUESTION: 5
#15.5 In the block diagram shown, the "antenna switch": 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

switches the transmitter output to the dummy load for tune-up purposes 

switches the antenna from transmit to receive 

switches the frequency of the antenna for operation on different bands 

switches surplus output power from the antenna to the dummy load to avoid distortion. 

% ans 1 

%QUESTION: 6
#15.6 In the block diagram shown, the "antenna tuner": 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

adjusts the resonant frequency of the antenna to minimize harmonic radiation 

adjusts the resonant frequency of the antenna to maximise power output 

changes the standing-wave-ratio on the transmission line to the antenna 

adjusts the impedance of the antenna system seen at the transceiver output 

% ans 4 

%QUESTION: 7
#15.7 In the block diagram shown, the "dummy load" is: 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

used to allow adjustment of the transmitter without causing interference to 
others 

a load used to absorb surplus power which is rejected by the antenna system 

used to absorb high-voltage impulses caused by lightning strikes to the antenna 

an additional load used to compensate for a badly-tuned antenna system 

% ans 1 

%QUESTION: 8
#15.8 In the block diagram shown, the connection between the SWR bridge and the 
antenna switch is normally a: 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

twisted pair cable 

coaxial cable 

quarter-wave matching section 

short length of balanced ladder-line 

% ans 2 

%QUESTION: 9
#15.9 In this block diagram, the block designated "antenna tuner" is not normally necessary when: 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

the antenna input impedance is 50 ohms 

a half wave antenna is used, fed at one end 

the antenna is very long compared to a wavelength 

the antenna is very short compared to a wavelength 

% ans 1 

%QUESTION: 10 
#15.10 In the block diagram shown, the connection between the "antenna tuner" 
and the "antenna" could be made with: 
<img src = "hfsta.gif" align = center width = 600 height = 170> 
<totallines = 16 >

three-wire mains power cable 

heavy hook-up wire 

50 ohm coaxial cable 

an iron-cored transformer 

% ans 3 

