Electrical Adjustments; Base Unit Section - Sony SPP-S9101 Service Manual

5-1. BASE UNIT 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 base unit in the Continuous Receive mode (CHI, LNA
ON, 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 IC501 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: TP515˜ TP567 (GND)
frequency counter
+
–
Procedure:
1. Short TP515 (GND) and TP567 (GND) on the BASE MAIN
board in the base unit.
2. Place the base unit in the Continuous Transmit more (CH1, High
power).
3. Measure the ANT OUT frequency of the RF module in the base
unit 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.
22

ELECTRICAL ADJUSTMENTS

TP558: RXIP
TP557: RXIN
+
TP556: RXQP
–
TP555: RXQN
TP567: GND
ANTENNA TERMINAL
ANTENNA TERMINAL
SECTION 5
3. Checking TX Output
Setting:
peak power meter
Procedure:
1. Place the base unit in the Continuous Transmit more (CH1, High
power).
2. Measure the ANT OUT output of the RF module in the base unit
using a peak power meter.
3. Confirm that the measured output is 85 mW (MIN 30 mW).
4 .Also, execute steps 1 through 3 for the channels 10 and 20.
CH10: 80 mW (MIN 25 mW)
CH20: 80 mW (MIN 25 mW)
+
ANTENNA TERMINAL
–