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necessary to print the log file during the testing.
(3) RF Output Connections
(a) Connect the RF OUTPUT RF1 connector of the tester to the input
of the spectrum analyzer with an RF cable (RFC1).
(b) Connect the RF OUTPUT RF2 connector of the tester to the input
of the 20-dB RF attenuator with an RF cable (RFC2).
(c) Connect the output of the 20-dB RF attenuator to the RF IN
connector (input) of the VMU tuner with an RF cable (RFC3).
(d) Connect a BNC tee adapter T2 to the VIDEO OUT connector of the
VMU tuner.
(e) Connect the input of the video monitor to the BNC tee adapter T2
with a video cable (VC5).
(f) Disconnect the RFC2 cable from the RF OUTPUT RF2 connector of
the tester.
(g) Connect BNC 50-W terminators to the RF OUTPUT RF2, RF3 and RF4
connectors of the tester.
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Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
C. Warm-up and Adjustments
(1) Initial Conditions
(a) Make sure that the power switches of all units in the test setup
are set to OFF.
(b) Set the switches as follows:
VMU Tuner
SWITCH POSITION
POWER OFF
ADJUST-NORMAL NORMAL
EXT-INT INT
(2) Energization of Test Equipment
(a) Set the power switches of the units shown below to ON:
· Video pattern generator
· Impedance converter
· Spectrum analyzer
· VMU tuner
· Video monitor
· Oscilloscope
(b) Set the tester's POWER switch to ON. You will hear the fan
sound and 400-Hz hum from the UUT.
NOTE: The tester's POWER switch controls the 400-Hz AC power to
the UUT.
(c) Give the units a warm-up time of 2 hours or more, during which
do the adjustments and setting given in (3), (4) and (5). You
can also do the first part of the functional testing before the
warm-up time comes.
NOTE: A warm-up time of 2 hours or more is necessary for the UUT
to measure its RF output levels. A warm-up time of 30
minutes or more is necessary for some of the instruments
such as the spectrum analyzer.
Page 122.02
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Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
(3) Video Input Adjustments
(a) Set the video pattern generator for a white-raster output.
(b) Get a video signal waveform as shown in Figure 103A with the
oscilloscope set as follows:
ITEM SETTING
CH1 Coupling AC.
CH1 Sensitivity 0.2 V/division.
Sweep Time 10 ms/division.
Trigger Source CH1.
Trigger Coupling DC or TV line (TV horizontal)
Trigger Slope Negative (-)
(c) Adjust the video signal output of the video pattern generator
accurately to 1.0 Vp-p in amplitude as measured on the
oscilloscope.
(d) Set the CH1 sensitivity of the oscilloscope to 0.5 V/division,
and make sure that the amplitude of the video signal is 1 Vp-p.
(e) Disconnect the BNC tee adapter T1 from the VIDEO INPUT CH1
connector of the tester with the VC1 and VC2 cables as
connected.
(f) Make sure that the amplitude of the video signal is increased
to:
· 2 Vp-p if the output impedance of the video pattern generator
is 50 W.
· 2.5 Vp-p if the output impedance of the video pattern generator
is 75 W.
(g) Connect the BNC tee adapter T1 to the VIDEO INPUT CH1 connector
of the tester.
(h) Set the CH1 sensitivity of the oscilloscope to 0.2 V/division.
Page 122.03
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COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
IF YOU USE THE IMPEDANCE CONVERTER OR IF THE VIDEO PATTERN GENERATOR GIVES
AN OUTPUT WITH AC COUPLING, YOU WILL SEE BLURS ON THE WAVEFORM AS SHOWN
BELOW.
(100 IRE)
(40 IRE)
(140 IRE)
1 Vp-p
0.71 Vp-p
0.29 Vp-p
BLUR
BLUR
BLUR
MEASURE THE
AMPLITUDE
BETWEEN THE
BOTTOM LINES
OF BLURS.
WAVEFORM
WAVEFORM
WITH DC
COMPONENT
CORRECT
REMOVED
BLUR
H SYNC
100% WHITE
SYNC PULSE
IF YOU SEE THE BLURS ON THE WAVEFORM, MEASURE THE AMPLITUDE BETWEEN THE
BOTTOM SIDES OF THE TOP AND BOTTOM BLURS.
GENERAL INSTRUCTIONS TO MEASURE
THE AMPLITUDE OF BASEBAND VIDEO SIGNAL
Figure 103A
Page 122.04
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Matsushita Avionics Systems Corporation
COMPONENT MAINTENANCE MANUAL
PART NUMBER RD-AA5002 SERIES
23-32-47
(4) Spectrum Analyzer Setting
Set the spectrum analyzer for RF carrier measurements of 130 thru
330 MHz in frequency and the level as given below:
　
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