XR-C6093SP - Sony Car Audio Service Manual (repair manual). Page 15

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L-CH Stereo separation: A-B
R-CH Stereo separation: C-D
The separations of both channels should be equal.

Specification: Separation more than 26 dB

Adjustment Location: See page 17.

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.

 0 dB=1 µV

When the tuner unit is defective, replace it by a new one be-
cause its internal block is difficult to repair.

 Adjust the tuner section in the sequence shown below.

1. FM Auto Scan/Stop Level Adjustment.
2. FM Stereo Separation Adjustment.
3. MW Auto Scan/Stop Level Adjustment.
4. FM Polar VCO Adjustment.
5. FM Polar Pilot Adjustment.

[SOURCE]

 button: FM 1

Procedure:
1. Tune the set to 98.0 MHz.
2. Connect the digital voltmeter to TP (SD) on MAIN board.
3. Adjust RV2 on TU1 so that the reading on the digital voltme-

ter changes point from low to high.

Adjustment Location: See page 17.

[SOURCE]

 button: FM 1

+
–

TP (SD)

MAIN board







digital 
voltmeter

FM RF signal 

generator

dummy

antenna

Carrier frequency : 98.00MHz
Output leve

: 20 dB (10.0 

µ

V)

Mode

: mono

Modulation

: 1 kHz, 22.5 kHz deviation (30 %)

antenna
terminal

set

50 

Ω

50 

Ω

+
–

FM RF signal 

generator

dummy

antenna

Carrier frequency 
Output level         
Mode                   
Modulation          

: 98.00MHz
: 70 dB (3.2 mV)
: stereo
: main : 1 kHz, 20 kHz deviation (26.7 %)
  sub : 1 kHz, 20 kHz deviation (26.7 %)
  pilot : 19 kHz, 7.5 kHz deviation (10 %)
 

antenna
terminal

set

50 

Ω

50 

Ω

4 

Ω

level 

meter

speaker out terminal