Incoming Inspection
External Reference
1. Press the FACTO
RY button to restore the factory preset.
2. Connect a 525/270 10-bit shallow ramp signal from a DVG1 module to the
SDI A input of t
he unit under test.
3. Terminate the loopthrough.
4. Apply an NTSC signal to the External Reference input from the Analog
Signal Generator. Install a termination on the loopthrough.
5. Press the EXT REF button on the instrument front panel.
6. The status bar in the lower left-hand corner of the display should display
Ref: NTSC.
7. Press the DISPLAY SELECT 4 button, then WFM,andthenFIELD.
8. Verify that both WFM tiles are stable.
9. Record Pass or Fail for NTSC Lock in the test record.
10. Remove
the NTSC signal from the reference input.
11. Both WFM tiles should "unlock" and scroll.
12. The status bar in the lower left-hand corner of the display s hould display
Ref: Ext. Missing.
13. Record Pass or Fail for Ref Missing in the test record.
Waveform Rasterizers Specifications and Performance Verification 5 9