31
F. PLAYBACK PHASE ADJUSTMENT (See Fig. 5-6)
Phase generator (PG) shifter decides the VIDEO HEAD switching point when a TAPE is played back.
In case the Phase generator (PG) shifter isn't correctly tuned, HEAD switching noise or vertical jitter may
occur.
a. Connect the PATH ADJ. FIXTURE to PT01 of the MAIN CIRCUIT BOARD.
b. Play the ALIGNMENT TAPE (COLOR BAR SIGNAL OR MONOSCOPE SIGNAL)
c. Connect the channel-1 scope probe to the S/W PULSE TEST PIN of the PATH ADJ. FIXTURE.
d. Connect the channel-2 scope probe(1V/div.) to the VIDEO OUT of the MAIN CIRCUIT BOARD.
e. Play back the ALIGNMENT TAPE.
f. Adjust the PG volume for time interval of 6.5H±0.5H between switching pulse and V-sync signal.
TEST POINTS
S/W PULSE TEST PIN
PATH ADJ. FIXTURE
VIDEO OUT
MAIN CIRCUIT BOARD
MEASURING EQUIPMENT
OSCILLOSCOPE
ADJUSTMENT
VR595 (PG SHIFTER)
MAIN CIRCUIT BOARD
Fig. 5-6 PLAYBACK PHASE ADJUSTMENT
Summary of Contents for GB14H3
Page 5: ...4 CIRCUIT BLOCK DIAGRAM ...
Page 12: ... 11 SCHEMATIC DIAGRAM ...
Page 13: ... 12 SCHEMATIC DIAGRAM ...
Page 14: ...13 EXPLODED VIEW 1 14H3 ...
Page 15: ...14 EXPLODED VIEW 2 14H4 ...
Page 16: ...15 EXPLODED VIEW 3 20H3 ...
Page 17: ...16 EXPLODED VIEW 4 20H4 ...
Page 18: ...17 EXPLODED VIEW 5 21H4 ...
Page 19: ......
Page 20: ......
Page 58: ...3 1 2 1 WIRE DIAGRAM 1 2WIREDIAGRAM ...
Page 62: ...7 2 1 2 PARTS LOCATION OF FRONT LOADING ASS Y A TOP VIEW B FRONT VIEW ...
Page 92: ...37 6 EXPLODEDVIEWANDPARTSLIST 6 1 EXPLODEDVIEWOFDECKASS Y TOPVIEW ...
Page 93: ...38 6 2 EXPLODEDVIEWOFDECKASS Y BOTTOMVIEW ...
Page 94: ...39 6 3 EXPLODEDVIEWOFF LASS Y ...
Page 95: ...40 ...
