– 11 –
SECTION 4
ELECTRICAL ADJUSTMENTS
As a front-end (TB101) is difficult to repair if faulty, replace it with
new one.
Please note, however, that the following adjustments are possible:
AM Section Adjustment
AM Tuned Level Adjustment
Note: FM Tuned Level Adjustment Should be performed after this
AM Tuned Level Adjustment.
Setting:
Band: AM or MW
TUNER SECTION
0 dB=1 µV
FM Stereo Separation Adjustment
Setting:
Procedure:
Turn the set to 98 MHz.
set
FM RF SSG
+
–
level meter
J101 (OUTPUT)
FM ANTENNA
terminal (TM101)
Carrier frequency: 98 MHz
Output level: 1 mV (60 dB)
Modulation:
Main (1 kHz): 33.75 kHz dev. (45%)
Sub (1 kHz): 33.75 kHz dev. (45%)
Pilot (19 kHz): 7.5 kHz dev. (10%)
47 k
Ω
FM stereo
VTVM VTVM
signal generator
connection reading (dB)
output channel
L-CH L-CH A
B
R-CH L-CH Adjust SEP (W) for
minimum reading.
R-CH R-CH C
D
L-CH R-CH Adjust SEP (W) for
minimum reading.
L-CH Stereo separation: A – B
R-CH Stereo separation: C – D
The separations of both channels should be equal.
Adjustment Location: Main board (TB101) (See page 13)
Procedure:
1. Set AM RF SSG output level to 76 dBµ so that the input level
becomes 50 dBµ .
2. Tune the set to 999 kHz (at 9 kHz step) or 1,050 kHz (at 10 kHz
step).
3. Adjust AM TUN (W) so that the TUNED light up.
Adjustment Location: Main board (TB101) (See page 13)
FM Section Adjustment
FM Tuned Level Adjustment
Setting:
Band: FM
AM RF SSG
loop antenna
set
loop antenna of
accessories
60 cm
AM ANTENNA
terminal (TM101
Carrier frequency: 999 kHz (at 9 kHz step)
Modulation: 400 Hz 30%
Output level: 6.3 mV (76 dB
µ
)
1,050 kHz (at 10 kHz step)
Procedure:
1. Supply a 17.8 µV (25 dBµ ) 98 MHz signal to the ANTENNA
terminal.
2. Tune the set to 98 MHz.
3. Adjust FM TUN (W) so that the TUNED light up.
Adjustment Location: Main board (TB101) (See page 13)
set
FM ANTENNA terminal (TM101
FM RF SSG
Carrier frequency: 98 MHz
Modulation: 1 kHz, 75 kHz deviation
Output level: 17.8
µ
V (25 dB
µ
)
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TEL 13942296513 QQ 376315150 892498299
TEL 13942296513 QQ 376315150 892498299
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