Handset Section - Sony SPP-111 Service Manual

HANDSET SECTION

Note:
• Apply 3.6 V dc from regurated DC power supply.
• Perform the adjustment at TEST1CH (26CH : 43.780 MHz) as a
rule.
• Set to handset manual test mode. (Refer to page 9)
TX SECTION ADJUSTMENT
TX VT Adjustment
Setting :
digital voltmeter
+
–
Procedure :
1. The digital voltmeter connected TP6 (TX VT) to TP30
(TX GND).
2. Adjust the L52 for 0.9 ± 0.05 V reading on the digital
voltmeter.
RX VT Adjustment
Setting :
digital voltmeter
+
–
Procedure :
1. The digital voltmeter connected TP5 (RX VT) to TP3
(RX GND).
2. Adjust the L102 for 3.0 ± 0.05 V reading on the digital
voltmeter.
TP6 (TX VT)
TP30 (TX GND)
TP5 (RX VT)
TP3 (RX GND)
RX SECTION ADJUSTMENT
RX LEVEL Adjustment
Note:
• Perform the adjustment at TEST1CH (26CH : 43.780 MHz) as a
rule.
Setting :
VOL switch : M
FM RF
signal generator
Carrier frequency : 43.780 MHz
Modulation
Deviation
Output level
level meter
+
–
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 : –9.5 to –15.5 dBV
RSSI Hi Adjustment
Note:
• Perform the adjustment at TEST1CH (26CH : 43.780 MHz) as a
rule.
Setting :
AF oscillator
Output: 20 Hz
oscilloscope
(DC range)
+
–
Procedure :
1. Use the oscilloscope to confirm the FM RF signal generator
input (AF) signal waveform and RSSI signal, and use the
RV101 so that they are synchronized (duty is synchronized).
RSSI output waveform
0 V
Adjust so that they
synchronize at 0 V.
Adjustment Location : hand main board (See page 15)
– 14 –
TP2
TP3 (RX GND)
: 1 kHz
: FM 3 kHz
: 60 dBµV (1 mV) (EMF)
TP26 (SP)
TP27 (SP)
FM RF
signal generator
TP2
TP3 (RX GND)
Carrier frequency : 43.780 MHz
Modulation : 20 Hz (EXT)
Deviation : AM 50%
Output level : 5.5 dBµV (1.88 µV) (EMF)
TP9 (SIG IN)
TP3 (RX GND)
AF oscillator
EXT signal
20 Hz
RSSI WAVEFORM