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maximum limit, or click on the "FAIL" if the RF output level is
higher than the maximum limit.
(c) Make sure that you put in the "PASS" or "FAIL" results correctly
for all channels, then click on the "NEXT" button.
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C. Video Level Check at Z = 50 W
(1) You will see the "VIDEO LEVEL CHECK AT Z = 50 OHMS" window as shown
in Figure 125, 125A or 125B.
NOTE: If you click on the "BACK" button, you can go back to the "RF
LEVEL CHECK: RF STOP" window.
Do as follows:
(a) Disconnect the RFC1 cable from the tester's RF OUTPUT RF4
connector and disconnect the BNC 50-W terminator from the
tester's RF OUTPUT RF1 connector.
(b) Connect the RFC2 cable from the VMU tuner input to the tester's
RF OUTPUT RF1 connector and connect the BNC 50-W terminator to
the tester's RF OUTPUT RF4 connector.
(c) Make sure that the impedance selector switch is set to 50W.
(d) Connect the BNC tee adapter T1 to the tester's VIDEO INPUT CH1
connector.
(e) Make sure on the oscilloscope that the video signal amplitude is
1.0 Vp-p, then disconnect the VC4 cable from the BNC tee adapter
T1.
(f) Connect the VC4 cable to the BNC tee adapter T2 to measure the
video output of the VMU tuner.
(g) Set the VMU tuner for reception of CH1 ("01" on the CH display
and "151.25" on the FREQ display).
(h) Make sure that the frequency is shown for each channel (ref.
Figure 125, 125A or 125B).
(i) Measure the video output level of the VMU tuner on the
oscilloscope.
(j) Click on the "PASS" if the video output level is within the
minimum-maximum limits, or click on the "FAIL" if the video
output level is too high or too low.
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(k) Do steps (d), (g), (i) and (j) for CH2 thru CH12. For part
numbers RD-AA5002-23 and RD-AA5002-25, do as follows for the
channel(s) specified:
UUT OPERATION CHANNEL(S)
RD-AA5002-23 Set the impedance selector switch to
100W before you do step (d).
CH12
RD-AA5002-25 Set the impedance selector switch to
100W before you do step (d).
CH7 thru CH12
(l) Make sure that you put in the "PASS" or "FAIL" results correctly
for all channels, then click on the "NEXT" button.
"VIDEO LEVEL CHECK AT Z = 50 OHMS" WINDOW FOR RD-AA5002-12/22
Figure 125
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PART NUMBER RD-AA5002 SERIES
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"VIDEO LEVEL CHECK AT Z = 50 OHMS" WINDOW FOR RD-AA5002-23
Figure 125A
"VIDEO LEVEL CHECK AT Z = 50 OHMS" WINDOW FOR RD-AA5002-25
Figure 125B
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PART NUMBER RD-AA5002 SERIES
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D. Video Quality Check
You will see the "VIDEO QUALITY CHECK" window as shown in Figure 126.
NOTE: If you click on the "BACK" button, you can go back to the VIDEO
LEVEL CHECK AT Z = 50 OHMS" window.
"VIDEO QUALITY CHECK" WINDOW
Figure 126
Do as follows:
(1) Set the impedance selector switch on the impedance selector to 50W.
(2) Connect the BNC tee adapter T1 to the tester's VIDEO INPUT CH1
connector.
(3) Set the video pattern generator for a color-bar pattern output.
(4) Remove the VC4 cable from the BNC tee adapter T2.
(5) Connect the VC4 cable to the BNC tee adapter T1 to measure the UUT's
video input level on the oscilloscope.
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PART NUMBER RD-AA5002 SERIES
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(6) Make sure that the video signal amplitude is in a range between 0.95
and 1.05 Vp-p.
(7) Set the VMU tuner for reception of CH1.
(8) Make sure that the frequency is shown for each channel (ref. Figure
126).
(9) Monitor and examine the color-bar pattern on the video monitor.
(10) Click on the "PASS" if the video monitor shows the color-bar pattern
clearly and correctly, or click on the "FAIL" if not.
(11) Do steps (2), (7), (9) and (10) for CH2 thru CH12. For part numbers
RD-AA5002-23 and RD-AA5002-25, you must set the impedance selector
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COMPONENT MAINTENANCE MANUAL Video Modulator Unit (VMU)(69)
