Goldstar FFH-3785AX, ffh-376ax, FFH-378AX Service Manual
SECTION 2. ELECTRICAL
ADJUSTMENTS
This set has been aligned at the factory and normally will not require further adjustment. As a result, it is not recommended that any attempt is made to modificate any circuit. If any parts are replaced or if anyone tampers with the adjustment, realignment may be necessary.
IMPORTANT
1.Check Power-source voltage.
2.Set the function switch to band being aligned.
3.Turn volume control to minimum unless otherwise noted.
4.Connect low side of signal source and output indicator to chassis ground unless otherwise specified.
5.Keep the signal input as low as possible to avoid AGC and AC action.
TAPE DECK ADJUSTMENT
1. AZIMUTH ADJUSTMENT
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Deck Mode |
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Test Tape |
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Test Point |
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Adjustment |
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Adjust for |
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A Deck Playback |
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MTT-114 |
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Speaker Out |
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DECK Screw |
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Maximum |
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Azimuth Screw |
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B Deck Playback |
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MTT-114 |
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Speaker Out |
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Azimuth Screw |
Maximum |
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Electronic |
Dual-trace |
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Voltmeter |
synchroscope |
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Head |
Playback Mode |
Speaker Out |
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L ch |
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L out |
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CH1 CH2 |
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Test Tape |
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MTT-114 |
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R ch |
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GND |
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R out |
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Figure 1. Azimuth Adjustment Connection Diagram |
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2. MOTOR SPEED ADJUSTMENT |
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Deck Mode |
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Test Tape |
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Test Point |
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Adjustment |
Adjust for |
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Remark |
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Normal Speed |
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MTT-111 |
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Speaker Out |
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VR201 |
3kHz ± 1% |
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A Deck |
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HI-Speed |
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MTT-111 |
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Speaker Out |
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more than 5.4kHz |
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HI-Speed Dubbing Mode |
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Head |
Speaker Out |
Frequency Counter |
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Playback Mode |
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Test Tape |
L out |
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Unit |
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MTT-111 |
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Record/Playback |
R out |
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GND |
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head
Figure 2. Motor Speed Adjustment Connection Diagram
- 2-1 -
3. RECORD BIAS ADJUSTMENT
Deck Mode |
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Test Tape |
Test Point |
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Adjustment |
Adjust for |
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Rec/Pause |
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MTT-5511 |
ERASE HEAD |
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L203 |
60kHz±5kHz (Auto stop) |
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WIRE(PN202) |
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85kHz±5kHz(Auto Reverse) |
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Head |
Record/Playback |
PN202 |
Frequency Counter |
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and Pause Mode |
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Test Tape |
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Unit |
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MTT-5511 |
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Record/Playback |
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GND |
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head |
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Figure 3. Record Bias Adjustment Connection Diagram
4. TUNER ADJUSTMENT
(FM)
Item |
Test Point |
Adjustment |
Adjust for |
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DC Voltage |
Checker IC Pin 26, 28 |
L106 |
0V±50mV |
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FM Antenna |
Electronic |
OSCILLOSCOPE |
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Terminal |
Speaker |
Signal Generator |
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Unit |
GND |
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Figure 4. Tuner(S curve) Adjustment Connection Diagram
(AM)
Item |
Test Point |
Adjustment |
Adjust for |
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AM IF |
SPEAKER OUT |
L110 |
OUTPUT MAXZMUM |
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- 2-2 -
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