ICF-C121 - Sony Audio Service Manual (repair manual). Page 5

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Setting:
BAND switch: FM

Setting:
BAND switch: AM

Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally done
by the trimmer capacitors.

FM  FREQUENCY  COVERAGE  ADJUSTMENT

Adjust for a maximum reading on level meter.

L4

CT4

86.5 MHz

109.5 Hz

FM  TRACKING  ADJUSTMENT

Adjust for a maximum reading on level meter.

CT3

Frequency max

AM FREQUENCY  COVERAGE  ADJUSTMENT

Adjust for a maximum reading on level meter.

L2

CT2

520 kHz

1,650 kHz

AM  TRACKING  ADJUSTMENT

Adjust for a maximum reading on level meter.

L1

CT1

600 kHz

1,400 kHz

AM  IF  ADJUSTMENT

Adjust for a maximum reading on level meter.

T1

455 kHz

+
–

FM RF SSG

±

 22.5 kHz frequency

deviation by 400 Hz
signal

FM lead wire antenna terminal

speaker terminal

0.01 

µ

F

set

level meter

+
–

AM RF SSG

Put the lead-wire
antenna close to
the set.

30% amplitude
modulation by
400 Hz signal
Output level: as low as possible

set

speaker terminal

level meter

• Adjusting Location: RADIO board (Component Side)

Confirm that the reading on the frequency counter is 900       Hz.

If frequency is higher, change capacitor value of C101.
If frequency is lower, change resistor value of R101.

+
–

frequency counter

10 pF

IC101 pin 

@¶

+ 200
– 100

T1:AM IF

ADJUSTMENT

L1: AM TRACKING

ADJUSTMENT

CT3:FM TRACKING

ADJUSTMENT

CT1:AM TRACKING

ADJUSTMENT

CT4:FM FREQUENCY

COVERAGE
ADJUSTMENT

CT2:AM FREQUENCY

COVERAGE
ADJUSTMENT

L4: FM FREQUENCY

COVERAGE
ADJUSTMENT

L2: AM FREQUENCY

COVERAGE
ADJUSTMENT

IC1