Adjustments - Daewoo XG-318 Service Manual

Adjustments

4
Adjustments
2. TAPE SECTION
Output Level
Measurement
Point
47 kohm
R-CH
Input Level
Measurement
Point
L-CH
47 kohm
Test Tape be used
Tape
MTT-111N
MTT-114N
MTT-5511
HEAD ADJUSTMENT (AZIMUTH)
1. 10KHz test tape(example: MTT-114N) must be used for this adjustment.
2. Connect to VTVM or oscilloscope to the headphone jack or speaker terminal.
3. Press the play button.
4. Adjust the azimuth by using a screw driver to maintain the max. L&R output voltage.
5. Adjust tape A(1), tape B(2) respectively, Please secure the azimuth position by using locking paint.
RECORDING BIAS OSCILLATOR FREQUENCY ADJUSTMENT
1. Connect the frequency counter to TP603, GND.
2. Press the REC button.
±
3. Adjust L603 to obtain 80 KHz 500Hz
TAPE ALIGNMENT CHART
Step Item Reference Value Test Tape
3,015~3,025Hz MTT-111N
Normal
Tape Speed 3,000~3,010Hz MTT-111N
1
Adjustment
High
5,820~6,180Hz MTT-111N
Maximum Level
2
Azimuth Adjustment MTT-114N
Phase:Within90∞
Recording Bias Oscilla-
tor Frequency Adjust- ±
3
80 KHz 0.5 MTT-5511
ment
Test Tape : MTT-111N(3kHz)
Frequency Counter
MTT-5511(Blank)
Set
Output Level
Measurement Point
FIG. 1 : Tape Speed & Record Bias Oscillator
Frequency Adjust Circuit
L-CH
Peak
within
1 dB
within
R-CH 1 dB
Peak
Screw
Angle
L-CH R-CH
Screw Angle
Peak Peak
FIG. 3 : Tape Azimuth Adjust Head Screw & Waveform
Input Point
Scope
VTVM
Contents Use
3 KHz Tape Speed Adjustment
10 KHz Head Azimuth Adjustment
Blank Record Frequency Property
Adjust Point Test Point Note
Line Out L/R Confirm Wow & Flut-
RV601
Channel ter is within 0.35%
Confirm Tape Speed
Line Out L/R of end position after
RV601
Channel adjustment at tape
start position
Confirm High speed
Line Out L/R
after normal speed
- - - - - -
Channel
adjustment
Line Out L/R
Head Screw
Channel
Adjust with frequency
TP603,GND
counter connected.
L603
Adjust with Frequency
Counter Connected
Forward Reverse
Side Side
FIG. 2 : Tape Azimuth Adjust Location
(Record/Playback Head)
L-CH Oscilloscope
Test Tape
MTT-114N
(10kHz)
V H
Set
Output Level
Measurement Point
Screen Pattern
In Phase 45 90 135 180
Good Wrong
FIG. 4 : Tape Azimuth Adjust Circuit & Waveform
5
FIG.
FIG.1
FIG.1
FIG.1
FIG.2,3,4
FIG.1