Sony MDX-C7900 Service Manual page 19

AM (MW) Auto Scan/Stop Level Adjustment
Setting:
[SOURCE]
button (MDX-C7900): AM
[SOURCE]
button (MDX-C7900R): MW
15 pF
30
65 pF
AM RF signal
generator
AM dummy antenna
(50 )
set
antenna jack (J1)
Carrier frequency: 1000 kHz (MDX-C7900)
999 kHz (MDX-C7900R)
30% amplitude
modulation by
1 kHz signal
Output level : 33 dB (44.7 V)
Procedure:
1. Set to the test mode. (See page 18.)
[SOURCE]
2. Push the button and set to FM.
[MODE]
3. Push the button and set to AM (MDX-C7900) or MW
(MDX-C7900R).
Display
*2
SHUF
*3
TP
REG
4. Adjust with the volume RV1 on TU1 so that the "AM" or "MW"
indication turns to "AM0" or "MW0" indication on the dis-
play window.
But, in case of already indicated "AM0" or "MW0", turn the
RV1 so that put out light "0" indication and adjustment.
Display
*2
SHUF
*3
TP
REG
*2: MDX-C7900R is indicates "MW".
*3: MDX-C7900R is indicates "999".
Adjustment Location: See page 20.
RDS S-Meter Adjustment (MDX-C7900R)
Setting:
[SOURCE]
button: FM
FM RF signal
generator
antenna jack (J1)
0.01 F
Carrier frequency: 98.0 MHz
Output level : 35 dB (56.2 V)
Mode : mono
Modulation : no modulation
Procedure:
1. Set to the test mode. (See page 18.)
[SOURCE]
2. Push the button and set to FM.
Display
SHUF
REG
[10]
3. Push the preset button.
4. Adjust RV1 on MAIN board so that the display indication is
"15.8".
Display
SHUF
REG
Specification: Display indication : 15.6 to 16.4
Adjustment Location: See page 20.
– 19 –
Adjustment Location:
– SET UPPER VIEW –
set
RV1 RDS S-METER Adjustment
TU1
RV1 AM (MW) AUTO SCAN/STOP LEVEL Adjustment
RV2 FM AUTO SCAN/STOP LEVEL Adjustment
RV4 FM STEREO SEPARATION Adjustment
– 20 –