Sharp VC-MH80 Service Manual page 35

SERVO CIRCUIT ADJUSTMENT
ADJUSTMENT OF PAL SYSTEM HEAD
SWITCHING POINT
Alignment tape (VROCPSV)
Cassette
TP2202 (H. SW. P.) to CH-1
Test point
VIDEO OUT jack to CH-2
(CH-1 trigger slope switch at
side.)
1. Remove the front panel and play the alignment
tape. (VROCPSV)
(Playback picture on the monitor screen.)
2. Make for a moment short-circuit between TEST
jumpers 3 and 4 located on the timer PWB.
Be sure that all the fluorescent display tubes
light up into the TEST mode. (See Note below 0)
3. Press the PLAY button, in the automatic adjust-
ment mode.
4. Be sure that " )" appears in the fluorescent
display tubes flashing into the operating.
5. Stop the ' I)" a p p e a r s i n t h e f l a s h i n g o f
fluorescent displayed tubes at adjusted.
6. Press the " STOP" button oder in the return to
normal mode.
7. Make this checking of waveform on the
oscilloscope screen be as shown in Figure 5-2. just
after the head switching point have been
adjusted.
If it is out of specified value, press the " FF" or
" REW" button in the make sure the specifica-
tion.
Notes:
When the adjustment of HEAD SWITCHING
POINT, AUTO TRACKING function is invalid.
@When the cassette housing control ass' y is
removed, setup of mechanism operating mode.
2) Make a short-circuit between test jumpers 3 and
4 located on the timer PWB to center the
tracking.
3) AC power cord is plugged in.
4) You can make mechanism operating mode.
CH-1
I
ADJUSTMENT OF PAL SYSTEM SP/LP SLOW
TRACKING PRESET
Measuring
I
instrument
Mode
Cassette
Control
Specification
feed a video signal to the VIDEO IN jack. (See
note 8 below)
2. Set the tape speed in SP mode by using the
remote controller and record the signal on tape.
3. Rewind and play the tape where signal was
recorded in above step.
4. Press the " SLOW" button on the remote control,
and playback the recorded portion in the slow
mode.
5. Make for a moment short-circuit between TEST
jumpers 3 and 4 located on the timer PWB.
Make sure that all the fluorescent display tubes
light up into the TEST mode.
6. Look at the monitor screen and adjust the (+) or
disappears from the screen.
7. Press the " PLAY" button to return to normal
mode.
8. Play the tape a few seconds then press the
" SLOW" button again and make sure there is no
noise in the screen.
(For the LP mode put adjustment at the same
adjustment way as SP mode.)
Notes:
program was recorded by the unit being
adjusted.
is pluged in the AUDIO/VIDEO input terminals.
35
VC-MH80
6.5 +0.5H (lines) -i V-sync.
Playback
Self-recorded tape (SP/LP
mode)
(See Note below)
Tracking control buttons (+ ) or
Minimized noise on monitor
screen