nzart-exam-generator/files/N15.TXT
2016-12-30 23:01:50 +13:00

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% 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