1-16
XV-D721BK
XV-D723GD
Long-distance seek
Feed
Tracking
Hold (DC) during feed
Acceleration pulse at start;
deceleration pulse at stop
(each one)
(In the direction of search,
opposite to this figure)
Kick pulse (fine seek) is
inserted after long-
distance seek.
(Not one)
Kick pulse
Approx.
2.5V
(9) Neither picture nor sound is output
* Cannot search
a) Can the feed system be driven?
Check the waveform of TRSDRV signal (R273). --- Waveform between R274 and C271.
Search results in a change of duty
(three values with 2.5V at the center)
(The figure is exaggerated.)
Check the waveform of CN101 "1" and "2". --- After the driver (IC271)
b) Is kick available?
Check the TRDRV signal waveform from R289.
Check the waveform of CN101 "2" and "4" --- After the driver (IC271)
Although differs in amplitude and DC offset, the waveform is similar to that of R289
For short-distance search, the waveform
becomes roundish, not trapezoidal, and
voltage is low.
