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TUNER ADJUSTMENT
１．
１． VT ADJUSTMENT (AM)
１．
１．
Requirement
Measuring equipment: Digital multi-meter
Test point: TP1(FFE801 ④pin),GND
Adjustment point: L773
(1) Adjust the reception frequency of the main unit to 1710KHz.
(2) Adjust L773 until the test point voltage (VT) is 9.0V±0.5V.
(3) Adjust the reception frequency of the main unit to 530KHz.
(4) Check that the test point (VT) voltage is about 1.3V.
２．
２．
２． VT CHECK (FM)
２．
Requirement
Measuring equipment: Digital multi-meter
Test point: TP1(FFE801 ④pin),GND
(1) Adjust the reception frequency of the main unit to 108.0MHz.
(2) Check that the test point (VT) voltage is about 9.0V.
(3) Adjust the reception frequency of the main unit to 87.5MHz.
(4) Check that the test point (VT) voltage is about 2.5V.
３．
３． DC BALANCE ADJUSTMENT
３．
３．
Requirement
Measuring equipment: Digital multi-meter
Test point: TP4, 5
Adjustment point: L771
(1) Adjust the reception frequency of the main unit to 98.0MHz.
(2) Adjust L771 until the test point voltage difference between TP4 and TP5 is
TE
L 13942296513
0mV±20mV.
＜ ＜ ＜ ＜ AM ADJUSTMENT＞ ＞ ＞ ＞
For AM adjustment, do wiring and connection as in the following.
Standerd Signal Generaor
４． IF ADJUSTMENT
４．
４．
４．
Requirement
Measuring equipment: Oscilloscope or Millivoltmeter
Test point: TP7 (IC771 24pin), GND
Adjustment point: L772
(1) Adjust the setting of Standard Signal Generator (hereinafter S.S.G.) to 450KHz
of 30％ variation.
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(2) While looking at the waveform on the oscilloscope, reduce the output level all the
way.
(3) Adjust L802 until the waveform of the oscilloscope reaches the maximum.
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2 9
8
Q Q
3
6 7
1 3
1 5
SET
Rch
GND
co
.
-24-
9 4
2 8
DIGITAL MULTIMETER
TP1
GND
DIGITAL MULTIMETER
VT
GND
DIGITAL MULTIMETER
VT
GND
0 5
8
2 9
9 4
2 8
TP
Lch
Connect to the respective
measuring equipment
OSCILLOSCOPE
CH1
Lch
m
Rch
GND
9 9
V
V
V
9 9
GND
CH2
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