Performance Verification: DigitalS ection
4-16 WFM90D and WFM91D Service Manual
6. Check that the displayedvideo is 714 mV, 2% (approximately 1/4 major
division) from graticulebaseline to white bar (0 IRE to +100 IRE for 525 or
0 V to +700 mV for625).
7. Set the COMP SEL to BLUE.
8. Check that the displayedvideo is 714 mV, 2% (approximately 1/4 major
division) from graticulebaseline to white bar (0 IRE to +100 IRE for 525 or
0 V to +700 mV for625).
9. Set the COMP SEL to RED.
10. Check that the displayedvideo is 714 mV, 2% (approximately 1/4 major
division) from graticulebaseline to white bar (0 IRE to +100 IRE for 525 or
0 V to +700 mV for625).
11. Set the COMP SEL to Y.
12. Check that the displayedvideo is 1 V, 2% (approximately 1/4 major
division) from synctip to white bar (--40 IRE to +100 IRE for 525 or
--300 mV to +700 mV for 625).
13. Exit the digital waveformmenu.
Check Frequency Response
This procedureverifies the following requirement:
Flat Filter,1 V F ull Scale,50 kHz to 4.5 MHz, within 4%
1. Enter the Configure menu. SelectPRE SETS and then select DEFAULT.
2. Select the WFM display mode on the WFM90D or WFM91D monitor.
3. PressMEN U todisplay the waveform menu.
4. Change the SWEEP to 1H.
5. Press and hold MENU for two seconds to displaythe digital waveform
menu.
6. Set the COMP SEL to Yand exit the menu.
7. Set the digital signal generatorto output a 100% sweep signal.
8. Check that the variation in the peak-to-peakamplitude of the signal is less
than 4% fromthe beginning of the sweep to half-way between the last two
markers(0.25 major divisions on a 60% sweep or 0.4 major divisions on a
100% sweep to 4.5 MHz).