Sharp QT-90W Service Manual page 8

QT-90W
L109
MW BAR ANTENNA
MW
TRACKING fL
VR102
FM
DETECTION
T103
MW BAND
COVERAGE fL
T104
fL
SW1 BAND
COVERAGE
fH
CT102
T105
CT101
ROD
ANTENNA
MECHANISM SECTION
Step
Item
1 Head
adjustment
2 Bias Frequency
adjustment
3 Beat cancel
T201
TP5
REC
MAIN PWB
Figure 8-2 ADJUSTMENT POINTS
VCO
TP3
T106
13 12
17
18
MW IF
21
24
1
TP4
T107
T101
fL
SW1
TRACKING
fH
fL SW2 BAND
T102
fH COVERAGE
TP6 TP1
MAIN PWB
Figure 8-1 ADJUSTMENT POINTS
Condition
Playback test tape Connect VTVM and oscilloscope to
MTT-113 6.3 kHz speaker output
Record position Connect frequency counter to TP5 and
ground
Record position Same as step 3
SW601
TAPE MAIN
4
1
3
2
2
3
1
4
CON602 CN602
M601
TAPE
MOTOR
CON201 CN201
1
1
2
2
3
3
4
4
RECORD/
PLAY
PLAYBACK HEAD
BACK
ERASE HEAD
TP2
FM IF
IC101
9
8
T108
L103
CT104 TC1
TC3
CT103
fH
SW2
TRACKING TUNER P.V.C.
fL
MW
TRACKING fH
TAPE Section
Connection
TAPE
Erase Head
– 8 –
T201
TP5
fL
FM BAND
COVERAGE
fH
1
L102
fL FM
TC2
TRACKING
fH
TC4
MW BAND
COVERAGE fH
Adjust
Head fixing screw Adjust to get MAX.
(see Fig 8-3.) audio output
80 kHz ± 1 kHz
Adjust T201
(Bias Oscillation)
75 kHz ± 0.5 kHz
S201 from playback
to record
Record/
Head fixing
Playback
screw
Head
Figure 8-3
Output
Tape Mechanism