QT-CD161/141
– 6 –
MECHANISM SECTION
• Driving Force Check
PLAY: TW-2412
Over 120 g
Torque Meter
Specified Value
• Torque Check
Torque Meter
Specified Value
Play: TW-2111
25 to 65 g.cm
Fast Forward: TW-2231
60 to 130 g.cm
Rewind: TW-2231
60 to 130 g.cm
• Tape Speed
MTT-111 In motor
3,000
±
90 Hz
Output: Speaker
Teaminal
(CNP201 Load
resistance: 8 ohms)
Instrument
Connection
Specified
Value
Test
Tape
TAPE SECTION
Position of each switch or control
Volume control
Max
Function switch
Tape/Power Off
X-BASS
On
• Bias Oscillation
Adjustment Point
• Playback Amplifier Sensitivity Check
Instrument Connection
Test Tape
MTT-118
1.8 V
±
3 dB
Speaker Terminal
(Load resistance: 8 ohms)
Specified Value
ADJUSTMENT
Figure 6-2 ADJUSTMENT POINTS
• Head Azimuth
Torque Meter
Specified Value
MTT-114
Output: Speaker Terminal
(CNP201 Load resistance: 8 ohms)
Adjusting
Point
Specified Value
Instrument
Connection
L301
82 kHz
±
6 kHz
Pin 2 of CNP201
– 6 kHz
fL: Low-range frequency
fH: High-renge frequency
IF
450 kHz
1,720 kHz
T3
*1
Band
—
530 kHz
(fL): L4
*3
Coverage
1.4
±
0.05 V
Tracking
600 kHz
600 kHz
(fL): L3
*2
1,400 kHz
1,400 kHz
(fH):TC1
Test Stage
Frequency
Frequency
Display
Setting/
Adjusting
Parts
Instrument
Connection
TUNER SECTION
• FM RF
Signal generator: 1 kHz, 75 kHz dev., FM modulated
Band
—
87.5 MHz
(fL): L2
*1
Coverage
2.0
±
0.1 V
RF
90.0 MHz
90.0 MHz
L1
*2
(10~30 dB)
Test Stage
Frequency
Frequency
Display
Setting/
Adjusting
Parts
Instrument
Connection
*1. Input: Antenna,
Output: TP1
*2. Input: Antenna,
Output: Speaker Terminal
• Detection
Signal generator: 10.7 MHz, FM sweep generator
IF
10.7 MHz
98.00 MHz
T1(Turn
Input: Pin 1 of
the core of
IC1
T1 fully
Output: TP2
counter-
clockwise.
Test
Stage
Frequency
Frequency
Display
Setting/
Adjusting
Parts
Instrument
Connection
*1. Input: Antenna,
Output: Pin19 of IC2
*2. Input: Antenna,
Output: Speaker Terminal
*3. Input: Input is not connected,
Output: TP1
• AM IF/RF
Signal generator: 400 Hz, 30%, AM modulated
• VCO Frequency
Specified
Value
Instrument
Connection
VR1
76 kHz
±
200 Hz
Pin 13, pin 21 and
ground of IC2
Adjusting Point
Note:
After preparing the test circuit shown in Fig. 6-1, connect the
Pin 13, Pin 21 and ground of the IC2 with the test circuit, and
measure the value. At this time, apply a standard unmodulated
signal input and adjust the VCO.
Figure 6-1 VCO FREQUENCY TEST CIRCUIT
Pin 13 of IC2
Pin 21 of IC2
D
G
S
10 kohm
TO FREQUENCY
COUNTER
FET : 2SK19 or 2SK54
1
1
VCO
VR1
IC2
T3
L4
L2
IC1
L1
FM IF
T1
TC1
AM TRACKING
L3
AM BAR
ANTENNA
FM ROD ANTENNA
FM BAND
COVERAGE
T2
AM IF
TP2
FM RF
FM DET.
TP1
13
17
19
21
R26
R7
AM BAND
COVERAGE
MAIN PWB
fL
fH
