Performance Verification: AnalogS ection
4-10 WFM90D and WFM91D Service Manual
17. Adjust the peak-to-peakdetector Plus amplifier and input control fully
counterclockwise.
18. Adjust the sine wave generatorfor a display amplitude of 100 IRE (700 mV
PAL).
19. Note the digital multimeter readoutlevel or the oscilloscope DC level.
20. Set the sine wave generatorfrequency to 3.58 MHz (4.43 MHz PAL).
21. Adjust the sine wave generatoramplitude for exactly 100 IRE (700 mV
PAL)of display.
22. Check that the digital multimeter readoutlevel, or the oscilloscope DC level,
is within 7 mV of the readingnoted in step 19.
23. Set the sine wave generatorfrequency to 6 MHz.
24. Adjust the sine wave generatoramplitude for exactly 100 IRE (700 mV
PAL)of display.
25. Check that the digital multimeter readoutlevel, or the oscilloscope DC level,
is within 7 mV of the readingnoted in step 19.
26. Select X1 GAIN from the Operating menu.
27. Remove the dual-input couplerfrom the instrument.
28. Connect the function generatoroutput to the VIDEO IN connector using a
X10 (75 Ω) attenuator.
29. Select 1H SWEEP from the Operating menu.
30. Enter the Configurationmenu and select the INPUT category. Select
EXT REF and SLOW DC REST.
31. Set the function generatorto output a 60 Hz (50 Hz PAL)sine wave with a
display amplitude of 100 IRE (700 mV PAL)on the WFM90D or WFM91D
monitor.
32. Connect a blackburst signal to the REF IN connector. Do not terminate the
input.
33. Check that the display amplitude is ≥80 IRE (560 mV PAL).
34. Select FAST DC REST.
35. Check that the display amplitude is ≤10 IRE (70 mV PAL).
36. Select INT REF and SLOW DC REST from the Configuration menu.
37. Remove all input signals fromthe WFM90D or WFM91D monitor.