Service manual

21
A. Adjustment of the S/T GUIDE ROLLER
a. Check the Playing back with a E-180 TAPE.
b. Make sure that excessive tape wrinkle does not
occure at eatch S.T GUIDE ROLLER.
c. If tape wrinkle is observed at the S/T GUIDE
ROLLER, turn the guide roller screw until there
is not tape wrinkle.
B. Adjustment of the AC HEAD ASS’Y(TILT)
a. Play back a E-180 TAPE and check the running
status of lower side of GUIDE POST.
b. If there is any problem, Turn the AC HEAD
TILT SCREW until the running status improved
(Fig. 5.2)
C. Adjustment of the AC HEAD Height(Fig. 5.3)
a. Play back E-180 TAPE.
b. Make sure that the gap between the lower end of
AC head is 0.25m.
c. If the measurement of the gap is different from
the reference value 0.25m, turn the screw !,#
until the desired gap is obtained.
D. Adjustment of the AUDIO AZIMUTH(Fig. 5.4)
a. Play back the ALIGNMENT TAPE
(DP2 : SP, PAL, 6KHz)
b. Check the AUDIO output with a AUDIO
LEVEL METER.
c. Turn the AC HEAD AZIMUTH SCREW @
until the maximum AUDIO output(-9dBm ~ -
3dBm)is obtained.
E. Adjustment of the X-POSITION(Fig. 5.4 5.5)
a. Connect the PATH ADJ. FIXTURE to the PT01
on the MAIN CIRCUIT BOARD.
b. Play back theALIGNMENT TAPE
(DP2 : SP STAIR STEP).
c. Connect the S/W pin and ENVE pin of the
PATH ADJ. FIXTURE with the SCOPE
PROBE.
d. Insert the adjustment bar in the AC HEAD
ADJUST hole $ and adjust the X-POSITION of
the AC HEAD ASS’Y until the ENVE is
maximum when the VR is on the CENTER.
* Three is the possibility that an another
TRACKING CENTER can be occur when the
AC HEAD ASS’Y turned completely in the
counterclockwise direction, Hence adjust the X-
position with AC HEAD ASS’Y adhering
closely to the right side until the maximum
ENVE is obtained.
e. The adjustment of the X-POSITION finished,
check if the AUDIO LEVEL is degraded, then
readjustment of the AUDIO AZIMUTH is
required.
FIg.5.2 Adjustment of the AC HEAD ASS’Y
FIg.5.3 Adjustment of X-POSITION
FIg.5.4 Adjustment of AUDIO AZIMUTH, X-POSITION
S/W PULSE TEST PIN PATH ADJ. FIXTURE
ENVELOPE TEST PIN PATH ADJ.FIXTURE
Measurement Equipment OSILLOSCOPE
VR CONTROL PATH ADJ.FIXTURE
AC HEAD ADJUST HOLE ADJUSTMENT BAR
Test Point
Adjustment