Sony MDX-C7970/C7970R, Service Manual

Page: 19 / 74

– 19 –
FM Stereo
Level meter Level meter
signal generator
connection reading (dB)
output channel
L-CH L-CH
A
B
L-CH R-CH Adjust RV3 on TU1
for minimum reading.
R-CH R-CH
C
R-CH L-CH
D
FM Stereo
Level meter Level meter
signal generator
connection reading (dB)
output channel
L-CH L-CH
A
B
R-CH L-CH Adjust RV4 on TU1
for minimum reading.
R-CH R-CH
C
D
L-CH R-CH Adjust RV4 on TU1
for minimum reading.
FM Stereo Separation Adjustment (MDX-C7970)
Setting:
[SOURCE]
button : FM
FREQUENCY SELECT switch : FM 200 k (E model)
Procedure:
FM RF signal
generator
Carrier frequency : 97.9 MHz
Output level
: 70 dB (3.2 mV)
Mode : stereo
Modulation : main : 1 kHz, 33.75 kHz deviation (45%)
sub : 1 kHz, 33.75 kHz deviation (45%)
: 19 kHz pilot: 7.5 kHz deviation (10%)
0.01
µ
F
set
antenna jack (J1)
+
–
LINE OUT jack (CNP300)
level meter
10 k
Ω
FM Stereo Separation Adjustment (Wide) (MDX-C7970R)
Setting:
[SOURCE]
button : FM
[SHIFT]
button : ON (light up SET UP and PLAY MODE)
Preset
[4]
(PLAY MODE)
→
[5]
(
→
) buttons : WIDE mode
FM RF signal
generator
Carrier frequency : 98.00 MHz
Output level
: 70 dB (3.2 mV)
Mode : stereo
Modulation : main : 1 kHz, 33.75 kHz deviation (45%)
sub : 1 kHz, 33.75 kHz deviation (45%)
: 19 kHz pilot: 7.5 kHz deviation (10%)
0.01
µ
F
set
antenna jack (J1)
+
–
level meter
10 k
Ω
LINE OUT jack (CNP300)
(75
Ω)
Procedure:
1. Adjust the volume RV3 on FM/AM tuner unit (TU1) for the
best separation.
L-CH Stereo separation:
A
-
B
R-CH Stereo separation:
C
-
D
The separations of both channels should be equal.
Specification: Separation more than 24 dB
Adjustment Location: See page 22.
L-CH Stereo separation:
A
-
B
R-CH Stereo separation:
C
-
D
The separations of both channels should be equal.
Specification: Separation more than 30 dB
Adjustment Location: See page 22.