Sharp VC-GH60SM Serviceanleitung Seite 29

SERVO CIRCUIT ADJUSTMENT
ADJUSTMENT OF HEAD SWITCHING POINT
Measuring Dual-trace oscilloscope
instrument Colour TV monitor
Mode Playback
Cassette Alignment tape
Head
2
2LP
4
4HiFi
Test point Pin(2) of TP201 (H.SW.P.) to CH-
1, VIDEO OUT jack to CH-2
(CH-1 trigger slope switch at (+),
Internal trigger at CH-1 side.)
6.5 ± 0.5H (lines)
Specification
1. Remove the front panel and play the alignment tape.
2. Get TP801 short circuited or press press "TEST"key(47H)
at Universal remote control to call the test mode.
(LCD will blinking as tracking goes to center)
3. Press "PLAY" key.
Auto PG Mode will be ON and playback mark " > "
blinking.
4. Press "STOP" key
" > " blinking stops and auto adjustment finished.
5. Check that V-Sync is 6.5±0.5H and the waveform is as
shown in Figure 5-2.
Note:
For manual PG Adjustment,press FF or REW key at
the Test Mode to set the tracking in center.
CH-2
Video signal
CH-1
Head Switching Pulse
Figure 5-2.
Tape
CBZF
BBZG
CBZF
CBZF
6.5 ± 0.5H
V: 2V/div
ADJUSTMENT OF PAL SYSTEM FV (False
Vertical Sync) OF STILL PICTURE
Measuring Colour TV monitor
instrument
Mode Playback still
Cassette Self-recorded tape (SP/LP,EP mode)
(See Note below 1)
Control Tracking control buttons (+) or (-)
Specification No vertical jitter of picture
1. Play a self-recorded tape.
2. Press the PAUSE/STILL button to freeze the picture.
3. Adjust (+) or (-) TRACKING buttons on the remote
control so that the vertical jitter of the picture is mini-
mized.
Note:
1 Self-recorded tape is a cassette which program was
recorded by the unit being adjusted.
2 The FV goes back to the it's initial state when the unit
is put into the system controller reset mode due to
power failure,etc.
In this case, preset the FV once again.
Y/C CIRCUIT ADJUSTMENT
CHECKING OF VIDEO E-E LEVEL
Measuring Oscilloscope
instrument
Mode E-E or Record
Input signal EIA colour bar (1.0Vp-p)
Test point VIDEO OUT jack
1.0 ± 0.2 Vp-p
Specification
1. Connect a 75 ohm terminating resistor to the VIDEO
OUT jack and connect an oscilloscope across this
termi-nating resistor.
(See Note below.)
2. Feed a colour bar signal to the VIDEO IN jack.
3. Make sure that the E-E signal amplitude is 1.0Vp-p as
shown in Figure 5-3.
Figure 5-3.
Note:
If the 75 ohm terminating resistor is missing, the signal
amplitude will be doubled.
29
VC-GH61GM/SM,GH611GM
VC-GH60SM,GH600SM,GH601SM
VC-FH310GM/SM
1.0 Vp-p