ICF-CD873L - Sony Audio Service Manual (repair manual). Page 8

Read Sony ICF-CD873L Service Manual online

– 8 –
AM  IF  ADJUSTMENT
Adjust for a maximum reading on level meter
T1
450 kHz
MW  FREQUENCY  COVERAGE  ADJUSTMENT
Adjustment Part
Frequency Display
Reading on Digital Voltmeter
L4
531 kHz
2.8 V
Confirmation
1,602 kHz
less than 10.5 V
MW  TRACKING  ADJUSTMENT
Adjust for a maximum reading on level meter
L3-1
621 kHz
CT2
1,404 kHz
LW  FREQUENCY  COVERAGE  ADJUSTMENT
Adjustment Part
Frequency Display
Reading on Digital Voltmeter
CT4
153 kHz
2.2 V
Confirmation
279 kHz
less than 9.5 V
LW  TRACKING  ADJUSTMENT
Adjust for a maximum reading on level meter
L3-2
162 kHz
CT3
243 kHz
FM  FREQUENCY  COVERAGE  ADJUSTMENT
Adjustment Part
Frequency Display
Reading on Digital Voltmeter
L2
87.5 MHz
2.1 V
Confirmation
108 MHz
9.7 V
FM TRACKING ADJUSTMENT
Adjust for a maximum reading on level meter
L1
87.5 MHz
CT1
108 MHz
Adjustment Location: MAIN board (See page 12)
FM  VCO Adjustment
Setting:
Procedure:
1. Connect the frequency counter to TP7, 8 as shown the figure
below.
2. Tune the set to 98 MHz.
3. Adjust RV1 for 76 kHz reading on the frequency counter.
Specified Value: 75.95 to 76.05 kHz
Adjustment Location: MAIN board (See page 12)
SECTION  5
ELECTRICAL  ADJUSTMENTS
TUNER  SECTION
0 dB=1 µV
[MW/LW]
Setting:
Function
: RADIO
Band switch : MW or LW
[FM]
Setting:
Function
: RADIO
Band switch : FM
• Repeat the procedures in each adjustment several times, and the
frequency coverage and tracking adjustments should be finally
done by the trimmer capacitors.
• Remove FM antenna in FM adjustments.
AM RF signal 
generator
30% amplitude
modulation by
400 Hz signal
Output level: as low as possible
Put the lead-wire
antenna close to 
the set.
+
level meter
set
32 
2
 (headphone) jack (J301)
FM RF signal
generator
22.5 kHz frequency
deviation by 400 Hz
signal
Output level: as low as possible
+
level meter
2
 (headphone) jack (J301)
set
32 
0.01 
µ
F
MAIN board
TP12 (FM IN)
digital voltmeter
100 k
MAIN board
TP53 (VT)
FM RF SSG
Carrier frequency: 98 MHz
Modulation: 400 Hz, 30% FM modulation
Output level: 0.1 V (100 dB)
MAIN board
TP12 (FM IN)
0.01 
µ
F
set
µ
F
TP8 (VCO)
+
frequency counter
33 k
TP7 (+B)
+
MAIN board
Page of 36
Display

Click on the first or last page to see other ICF-CD873L service manuals if exist.