Casio ZD-3 Service Manual page 25

Repair Item 4: FR and FF be operated cannot normally. Selected track number cannot be
searched.
or
Figure 14
All manuals and user guides at all-guides.com
4
Press FR or FF button.
Is the waveform
at pin 15 of IC701 like that
shown in figure 14 ?
No
Press FR or FF button.
Is the waveform
at pin 12 of IC701 like that
shown in figure 15 ?
No
Press FR or FF button.
Is pin 49 (GFS) of IC702
low ?
No
* IC702 is defective.
VC
or
VC
Figure 15
23
* Check circuit around and soldering
Yes
pins 12, 13, 14 and 15 of IC701.
* Check drive unit.
Yes
* Check drive unit.
Yes
* Check circuit around and soldering
pins 29, 30, 31, 37 and 38 of IC702.
VC
VC