Tektronix WFM700 Series, Service Manual

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Adjustments
WFM700 Series Waveform Monitors Service Manual
3- 7
This adjustment calibrates the Standard Definition RGB output amplitude from
the Reference Module.
1.
Connect the SD video generator to the Video Module under test using a 75
8
cable.
2. Set the SD video generator for a 525-format 100% color bar signal.
3. Connect the PIX G/Y output to the 75
8
input of the test oscilloscope using
a 75
8
cable. Use a 75
8
-to-50
8
adapter on the input of the test oscillo-
scope if necessary.
4.
Select the appropriate WFM700 Video Module (1 or 2) and input (A or B).
5. Press the CONFIG button.
6. Touch the Video Inputs/Outputs soft key, then Next Menu .
7. Touch the Output Active for SD soft key, then YPbPr .
8. Press the CONFIG button twice to exit the menu.
9. Set the test oscilloscope to view the first color bar. The following oscillo-
scope settings normally provide a usable display.
Vertical Scale 100 mV/div
Vertical Position –3.5 div
Horizontal Scale 5 us/div
Horizontal Trigger Position 50%
Trigger Slope Rising edge
Trigger Level 500 mV
10. Adjust R701 for a display of 700 mV on the test oscilloscope. Measure the
amplitude between the black level and the first color bar. See Figure 3--4.
11. Move the cable from the PIX G/Y to the PIX B/Pb connector.
12.
Set the test oscilloscope to view the signal. The following oscilloscope
settings normally provide a usable display.
Vertical Scale 100 mV/div
Horizontal Scale 10 us/div
Horizontal Trigger Position 10%
Trigger Slope Rising edge
Trigger Level 300 mV
13. Adjust R702 for a display of 700 mV on the test oscilloscope. Measure the
peak-to-peak amplitude of the waveform displayed on the oscilloscope. See
Figure 3--5.
SD GRB Output
Adjustment