XR-1800R - Sony Car Audio Service Manual (repair manual). Page 13

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4. Repeat the above adjustment for the REV PB mode.
5. Check that output level difference between FWD PB mode

and REV PB mode is within 4 dB.

Adjustment Location: PB head

Procedure:
1. Put the set into the FWD PB mode.
2. Adjust adjustment resistor for inside capstan motor so that the

reading on the speed checker or frequency counter becomes in
specification.

Specification: Constant speed

Adjustment Location: See page 16.

See the adjustment location from on page 16 for the ad-
justment.

FWD 

REV 











adjustment 
screws

+

–

speed checker

or

frequency counter

test tape
WS-48A
(3 kHz, 0 dB)

speaker out terminal

set

4 

Ω

Speed checker

Frequency counter

–2 to +3%

2,940 to 3,090 Hz

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 Noise Focus Adjustment
3. FM Stereo Separation Adjustment
4. FM Signal Meter Adjustment
5. MW Auto Scan/Stop Level Adjustment

[TUNER]

 button: FM 1

Procedure:
1. Tune the set to 98.0 MHz.
2. Connect the digital voltmeter to TP101 (SD) on MAIN board.
3. Adjust RV2 on TU100 so that the reading on the digital volt-

meter changes point from low to high.

Adjustment Location: See page 16.

FM RF signal 

generator

dummy

antenna

Carrier frequency : 98.0 MHz
Output level

: 28 dB (25.1 

µ

V)

Mode

: mono

Modulation

: 1 kHz, 22.5 kHz deviation (30%)

antenna
jack (CN900)

set

50 

Ω

50 

Ω

0.1pF

+
–

TP101 (SD)

MAIN board











digital 
voltmeter