Handset Section - Sony SPP-S9101 Service Manual

5-2. HANDSET SECTION

• Make the set in Test mode (see page 16)
1. Checking RX I&Q Output Level
Setting:
oscilloscope
level meter
+
–
SSG
Procedure:
1. Place the bandset in the Continuous Receive mode (CHI, LNA
AGC ON).
2. Set the SSG frequency to the frequency on CHI + 300 kHz, and
the RF output level to - 95 dBm.
3. Measure the output level of RXIN, RXIP, RXQN, and RXQP
with a level meter. At this time, confirm with an oscilloscope
that a sine wave of 300 kHz is output.
4. Confirm that the measured output level is -25.0 to -19.0 dB V.
IF IC401 was replaced (there is no ID data), the output level is -
30.0 to -24.0 dB V.
5. Also, execute steps 1 through 4 for the channels 10 and 20.
* For the frequency on each channel, see page 13.
2. Checking TX Center Frequency
Setting:
• short: TP820 ˜TP814 (GND)
frequency counter
+
–
Procedure:
1. Short TP555 (GND) and TP814 (GND) on the HAND MAIN
board in the handset.
2. Place the handset in the Continuous Transmit more (CH1, High
power).
3. Measure the ANT OUT frequency of the RF module in the hand
set using a frequency counter.
4. Coufirm that the measured frequency is 904.200 MHz ± 27kHz.
5. Also, execute steps 1 through 4 for the channels 10 and 20.
TP804: RXIP
TP803: RXIN
+
TP802: RXQP
–
TP801: RXQN
TP814: GND
ANTENNA TERMINAL
ANTENNA TERMINAL
3. Checking TX Output
Setting:
peak power meter
+
ANTENNA TERMINAL (TP812)
–
Procedure:
1. Place the handset in the Continuous Transmit more (CH1, High
power).
2. Measure the ANT OUT output of the RF module in the handset
using a peak power meter.
3. Confirm that the measured output is 62 mW (MIN 25 mW).
4. Also, execute steps 1 through 3 for the channels 10 and 20.
CH10: 64 mW (MIN 25 mW)
CH20: 64 mW (MIN 25 mW)
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