Test Equipment; Pre-Adjustment; Am Adjustment; Mw/Lw - Samsung RCD-M70 Service Manual

Alignment and Adjustments

1-1-1 Test Equipment

1. AM Standard Signal Generator (S.S.G) : 400Hz, 30% MOD
2. Oscilloscope
3. VTVM
4. Frequency counter
5. Loop antenna
6. Dummy load (3Ω)
7. DC voltmeter

1-1-2 Pre-Adjustment

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

1-1-3 AM Adjustment

Item Connection
Step
Intermediate
1
frequency (IF) Figure 1-5
adjustment
Figure 1-4
AM frequency
2
coverage
Connect DC voltmeter to AM
adjustment
VT(OR10) and GND
3
4
Figure 1-5
AM tracking
adjustment
5 -
AM Signal
Generator
Test Loop
Antenna
1-2
SSG.FREQ. FREQ. Setting Adjust. Point
450 KHz IT 2
522 KHz
522 KHz OT 1
-
1611KHz
- OCT2
594 KHz 594 KHz MW-ANT
- - -
AM VT(OR10)
SET
Input
GND
DC Voltmeter
Figure 1-4
VTVM
Speaker
AM-ANT
Terminal
IN
SET
60 cm
GND
)
Ω
Dummy Load(3
Figure 1-5

1-1-4 MW/LW

Step Item
Intermediate
1
frequency (IF)
adjustment
MW frequency
2
coverage
adjustment
3
4
MW tracking
adjustment
5
6
Remark
LW frequency
coverage
adjustment
7
Maximum output
8
1.0V
LW tracking
adjustment
4.6V
9
Maximum output
Non Adjust
Oscilloscope
OUT
FREQ. Setting Adjust.
Connection SSG.FREQ.
Fig 1-5
450 KHz 522 KHz
522 KHz
-
Fig 1-4
1611 KHz
-
594 KHz
594 KHz
Fig 1-5
-
1404 KHz
-
144 KHz
Fig 1-4
-
290 KHz
170 KHz
170KHz
Fig 1-5
-
270KHz
Remark
Point
IT2
Maximum output
OT1 1.0V(LOW)
OCT2
4.6V(HIGH)
MW ANT
Maximum output
COIL
-
NON Adjust
OT2 0.7V(LOW)
3.1V(HIGH)
OCT4
LW ANT
Maximum output
COIL
- NON Adjust
Samsung Electronics