Performance Verification: AnalogS ection
WFM90D and WFM91D ServiceManual 4-7
VerticalGain and Vertical Magnifier Registration
This procedureverifies the following requirement:
1 VoltFull Scale: 1 V input displayed within 1% of 140 IRE (1.00 V PAL).
X5 Gain: Gain accuracy within 5% with 1 V input signal. X5 Gain Registration:
≤1 major division of verticalshift from baseline between unmagnified and
magnified signal.
1. Set the multiburst generatorcontrols to C omposite and Multiburst.
2. Position the signal baselineto the graticule baseline, and then select
X5 GAIN from the Operatingmenu.
3. Check that the signal baseline is within 1 major division of the graticule
baseline.
4. Select X1 GAIN from the Operating menu.
5. Remove the signal and termination fromthe VIDEO IN connector.
6. Connect the output of the VACto the VIDEO IN connector. Do not
terminatethe input.
7. Set the VACfor a 999.9 mV output, with all of the buttons out except for
+LUM and NTSC (PALbutton for the WFM 91).
8. Check for a display amplitude of 140 IRE 1.4 IRE (1000 mV 10 mV
PAL).
9. Set the VACfor a 199.9 mV output.
10. Select X5 GAIN from the Operating menu.
11. Check for a display amplitude of 140 IRE 5 IRE (1000 mV 50 mV
PAL).
12. Select X1 GAIN from the Operating menu.
VariableGain Range and Vertical Position Range
This procedureverifies the following requirement:
VariableGain Range: Input signals between 0.8 V and 2 V can be adjusted to
140 IRE (1.0 V) display.160 mV and 400 mV for X5 Gain. Vertical Position
Range: 1 V signal canbe positioned so that peak white and sync tip can be
placed at blanking level, with the DC Restorer Clamp on, regardless of gain
setting.
1. Set the VACfor a 999.9 mV output.