Sony SPP-Q123, Руководство по обслуживанию

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SECTION 4
ELECTRICAL ADJUSTMENTS
BASE UNIT SECTION
Note:
• Apply 9V dc from regurated DC power supply.
• Perform the adjustment at T3CH (28CH : 49.910MHz) as a rule.
• Set to base unit machine test mode. (Refer to page 8.)
• Switch position :
S302 (DIAL MODE) : P(pulse)
TX SECTION ADJUSTMENT
• The electrolytic capacitor (10
µ
F/10V) connected TP23 (DET
OUT) to GND. (Only TX section adjustment)
TX VT Adjustment
Setting :
Procedure :
1. The digital voltmeter connected TP6 (TX VT) to TP19 (GND).
2. Adjust the L52 for 2.2 ± 0.05V reading on the digital voltmeter.
RX VT Adjustment
Setting :
Procedure :
1. The digital voltmeter connected TP5 (RX VT) to TP19 (GND).
2. Adjust the L101 for 2.4 ± 0.05V reading on the digital voltme-
ter.
RX SECTION ADJUSTMENT
RX Level Adjustment
Note:
• Perform the adjustment at T3CH (28CH : 49.910MHz) as a rule.
Setting :
Procedure :
1. Adjust the FL101 for the maximam reading on the level meter.
Also check that the output level is the specified values.
Specified Value : –2.6 to –10.6dBV
RSSI(H) Sensitivity Adjustment
Note:
• Perform the adjustment at T3CH (28CH : 49.910MHz) as a rule.
Setting :
Procedure :
1. Use the osclloscope to confirm the FM RF signal generator in-
put (AF) signal waveform and RSSI signal, and use the RV101
so that they are synchronized (duty is synchronized).
Adjustment Location :
+
–
digital voltmeter
TP6 (TX VT)
TP19 (GND)
+
–
digital voltmeter
TP5 (RX VT)
TP19 (GND)
FM RF
signal generator
Carrier frequency: 49.910 MHz
Modulation: 1 kHz
Deviation: 3 kHz
Output level: 60 dB
µ
V (1 mV) (EMF)
TP2
TP3 (RF GND)
FM RF
signal generator
Carrier frequency: 49.910 MHz
Modulation: 20 Hz (EXT)
Deviation: AM 50%
Output level: 6 dB
µ
V (2
µ
V) (EMF)
TP2
TP3 (RF GND)
AF oscillator
Output: 20 Hz
level meter
600
Ω
+
–
PBX tester
TP104
TP105
F.B. DC 48V
or
+
–
osclloscope
(DC range)
TP9 (SIG OUT)
TP19 (GND)
0V
Adjust so that they
synchronize at 0V.
RSSI output waveform RF signal EXT
signal 20Hz
RSSI WAVEFORM
RV101
FL101
L101
L52
– base main board (component side) –
TP105
TP9 (SIG OUT)
TP104
TP23 (DET OUT)
– base main board (conductor side) –
TP19 (GND)
TP5 (RX VT)
TP6 (TX VT)
TP2
TP3 (RF GND)
IC501