Yamaha DVX-700 Service Manual page 45

3. VFD CHECK
This menu is used to check the FL and FL driver.
Using the sub-menu, the display varies as shown below.
All segments ON (dimmer 100 %)
All segments OFF
All segments ON (dimmer 50 %)
Lighting of segments in lattice
Segment conditions of the FL driver and the FL tube are checked by turning ON and OFF all segments.
Next, the operation of the FL driver is checked by using the dimmer control. Then a short between segments next
to each other is checked by turning ON and OFF all segments alternately (in lattice). (In the above example, the
segments in the second row from the top are shorted.)
Lighting in lattice
Short Normal
DVR-700/NS-PSW700/NS-P700
3-1 ALL ON
3-2 ALL OFF
3-3 DIMMER
3-4 PATTERN
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