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Performance Verification: Analog Section
4-6
WFM90D and WFM91D Service Manual
Sweep Timing and Integral Linearity
This procedure verifies the following requirement:
Sweep Timing Accuracy: 5 s/Div. (1 Line), 10 s/Div. (2 Line), and 1.0 s/Div.
(2 Line + MAG), ᐔ2%. 0.2 s/Div. (1 Line + MAG) ᐔ3%. Integral Linearity:
ᐔ1%.
1. Connect the multiburst signal from the analog television signal generator to
the VIDEO IN connector on the WFM90D or WFM91D monitor, and to the
input on the frequency counter, using a T-connector, 75 Ω cable, and 75 Ω
in-line termination.
2. Set the multiburst generator controls to Low, Continuous, and Manual. Set
the output frequency to 100 kHz (as read on the frequency counter).
3. Check for one cycle per division, ᐔ1 minor division, over the center ten
graticule divisions.
4. Select 1H SWEEP from the Operating menu.
5. Set the multiburst generator frequency to 200 kHz.
6. Check for one cycle per division, ᐔ1 minor division, over the center ten
graticule divisions.
7. Adjust the multiburst generator frequency so that the cycles land exactly on
the first and tenth graticule marks.
8. Check that each cycle is within ᐔ0.5 minor division of a major graticule
mark.
9. Select MAG ON from the Operating menu.
10. Set the multiburst generator frequency to 2 MHz.
11. Check for one cycle per division, ᐔ1 minor division, over the center ten
graticule divisions, and also at both ends of the magnified sweep (using the
horizontal position control), ignoring the first and last cycle.
12. Set the multiburst generator frequency to 1 MHz.
13. Select 2H SWEEP from the Operating menu.
14. Check for one cycle per division, ᐔ1 minor division, over the center ten
graticule divisions, and also at both ends of the magnified sweep (using the
horizontal position control), ignoring the first and last cycle.
15. Select MAG OFF from the Operating menu.