SAMSUNG RCD-S70-S75 Schematics
1. Alignment and Adjustments
1-1 T uner
Samsung Electronics 1-1
FM THD Adjustment
Minimum Distortion (Figure 1-1)
SSG FREQ.
Adjustment
point
(FM-DET)
98 MHz
FM DETECTOR COIL
FM Search Level Adjustment
Adjust SVR1 so that “Voltage” of GND and
CON(6pin) is 0V (Figure 1-2)
Figure1-2 FM Auto Search Level Adjustment
Figure1-1 IF CENTER and THD Adjustment
SSG FREQ.
Adjustment
point
(SVR1)
98 MHz
BEACON
SENSITIVITY
SEMI-VR(10KΩ)
FM SSG
GND
26 dB
FM SSG
Output
GND
Speaker
Terminal
FM
Antenna
Terminal
Distortion Meter
Input
SET
Input
output
Oscilloscope
FM IN
FM Antenna
SET
10 kΩ
FREQ:1KHz
MOD : 40KHz DEV
Voltmeter
1-2 Samsung Electronics
1-1-1 T est Equipment
1-1-2 Pre-Adjustment
1-1-3 AM Adjustment
1. AM Standard Signal Generator (S.S.G) :400Hz, 30% MOD
2. Oscilloscope
3. VTVM
4. Frequency counter
5. Loop antenna
6. Dummy load (4Ω)
7. DC voltmeter
1. Check the source voltage
2. Press TUNER/BAND to select the AM(MW) function.
3. Set the EQ/S.BASS control to OFF position.
4. Set the volume control to approximaterly 50mw (4Ω)
Intermediate
frequency (IF)
adjustment
AM frequency
coverage
adjustment
AM tracking
adjustment
Figure 1-4
Connect DC voltmeter to
AM VT(JW8) and GND
1
2
4
5
3
Figure 1-5
Figure 1-5
450 KHz
594 KHz
Figure 1-4
SET
60 cm
AM Signal
Generator
Test Loop
Antenna
Speaker
Terminal
VTVM
IN
OUT
GND
Oscilloscope
AM-ANT
Figure 1-5
SET
AM VT(JW8)
GND
Input
DC V oltmeter
594 KHz
MW-ANT
-
-- -
1611KHz
-
-
522 KHz
522 KHz
AM-IF
MO
1.2V
Maximum output
Maximum output
No Adjustment
Remark
FREQ. Setting
Adjust. Point
SSG.FREQ.Item
Step
Connection
Alignment and Adjustments
Dummy Load(4Ω)
1-1-4 MW/LW
Intermediate
frequency (IF)
adjustment
MW frequency
coverage
adjustment
MW tracking
adjustment
Fig 1-4
1
2
4
5
3
Fig 1-5
594 KHz
594 KHz
MW ANT
COIL
-
OCT2
-
-
LW ANT
COIL
OT1
1.0V(LOW)
Maximum output
Maximum output
Remark
FREQ. Setting
Adjust.
Point
SSG.FREQ.
Item
Step
Connection
522 KHz
4.6V(HIGH)
1611 KHz
1404 KHz
-
6
Fig 1-4
-
144 KHz
OT2
0.7V(LOW)
-
290 KHz
OCT4
3.1V(HIGH)
LW frequency
coverage
adjustment
7
9
8
LW tracking
adjustment
Fig 1-5
170KHz
170 KHz
270KHz
-
-
Fig 1-5
450 KHz 522 KHz
IT2
Maximum output
-
No Adjustment
No Adjustment
No Adjustment
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