Rx Section - Sony WCS-999 Service Manual

3. TX Output Level Confirmation
Setting:
spectrum analyzer
TX BASE
board
1/4 λ sleeve antenna
more than 1 GHz
lead wire antenna (ANT1)
Procedure:
1. Connect the 1/4 λ sleeve antenna to a spectrum analyzer, and
put the antenna by the lead wire antenna (ANT1).
2. Set the [RF CHANNEL] switch (SW51) to [1].
3. Confirm that the value of spectrum analyzer satisfy specified
value.
4. Change the [RF CHANNEL] switch (SW51) to [2].
5. Confirm that the value of spectrum analyzer satisfy specified
value.
6. Change the [RF CHANNEL] switch (SW51) to [3].
7. Confirm that the value of spectrum analyzer satisfy specified
value.
Specified values: CH-1: –10 dBm to –20 dBm
CH-2: –10 dBm to –20 dBm
CH-3: –10 dBm to –20 dBm
4. VCO Voltage Adjustment
Setting:
digital voltmeter
CP52
+
Set
–
shield case
Procedure:
1. Connect a digital voltmeter to CP52 (the line of the TX BASE
board to the VCD board) and shield case (GND) of the VCO
board.
2. Set the [RF CHANNEL] switch (SW51) to [2].
3. Adjust CT1 on the VCO board so that the value of digital volt-
meter becomes 1.18 V.
4. Set the [RF CHANNEL] switch (SW51) to [1].
5. Confirm that the value of digital voltmeter satisfy specified
value.
6. Set the [RF CHANNEL] switch (SW51) to [3].
7. Confirm that the value of digital voltmeter satisfy specified
value.
Specified values: CH-2: 1.16 V to 1.20 V
CH-1: 0.87 V to 0.89 V
CH-3: 1.37 V to 1.39 V
5. TX Modulation Sensitivity Adjustment
Setting:
AF OSC
Frequency: 1 kHz
Output level: –50 dBV
+
receiver
–
MIC jack (J1)
unit
TX BASE
board
lead wire antenna (ANT1)
REC out plug
(P1)
Procedure:
1. Connect an AF OSC to the MIC jack (J1) on the TX BASE
board (transmitter unit).
2. Connect the REC out plug (receiver unit) to an audio analyzer.
3. Set the [RF CHANNEL] switch (SW51) to [1].
4. Adjust RV1 on the TX BASE board (transmitter unit) so that
the value of audio analyzer becomes –41 dBV.
5. Change the [RF CHANNEL] switch (SW51) to [2].
6. Adjust RV2 on the TX BASE board (transmitter unit) so that
the value of audio analyzer becomes –41 dBV.
7. Change the [RF CHANNEL] switch (SW51) to [3].
8. Adjust RV3 on the TX BASE board (transmitter unit) so that
the value of audio analyzer becomes –41 dBV.
Adjustment Location:
MIC jack – TX BASE BOARD –
(J1) (Component Side)
TX Modulation
Sensitivity Adjustment
1 t 2 t 3
RV3 CH-3
SW51
[RF CHANNEL]
RV2 CH-2
RV1 CH-1
RV51
TX Output Level
Adjustment
–VCO BOARD –
CT1
VCO Voltage
Adjustment
CP52
shield case
lead wire antenna (ANT1)
– 7 –

RX SECTION

1. Consumption Current Check
Setting:
regulated dc
power supply
battery
terminal 3
+
mA
–
battery
terminal #
Procedure:
audio
1. Connect a regulated dc power supply (1.5 V) and ampere meter.
analyzer
2. Set the [RF CHANNEL] switch (SW1) to [1].
3. Check that the value of ampere meter satisfy specified value.
Specified value: 55 mA to 65 mA
2. RX Frequency Adjustment
Setting:
digital voltmeter
+
–
lead wire
antenna (ANT1)
FM RF SSG
1/4 λ sleeve
antenna
Carrier frequency: 912.85 MHz
Modulation: 1 kHz, ± 20 kHz deviation
Output level: – 60 dBm
Procedure:
Connect the 1/4 λ sleeve antenna to a SSG, and put the an-
1.
tenna by the lead wire antenna (ANT2).
2. Connect a digital voltmeter to TP51 and TP102 on the RX
BASE board.
3. Connect REC out plug (P1) to an oscilloscope.
Set the [RF CHANNEL] switch (SW1) to [1].
4.
5. Adjust CT3 on the RX BASE board so that the value of digi-
tal voltmeter becomes 1.4 V.
6. Confirm that the waveform of oscilloscope is sine wave.
7. Change the carrier frequency of SSG to 913.75 MHz.
Change the [RF CHANNEL] switch (SW1) to [2].
8.
9. Adjust CT2 on the RX BASE board so that the value of digi-
tal voltmeter becomes 1.4 V.
10. Confirm that the waveform of oscilloscope is sine wave.
11. Change the carrier frequency of SSG to 914.35 MHz.
12. Change the [RF CHANNEL] switch (SW1) to [3].
13. Adjust CT1 on the RX BASE board so that the value of digi-
tal voltmeter becomes 1.4 V.
14. Confirm that the waveform of oscilloscope is sine wave.
3. RX Output Level Adjustment
Setting:
lead wire
antenna (ANT1)
FM RF SSG
Set
Carrier frequency: 913.75 MHz
Modulation: 1 kHz, ± 20 kHz deviation
Output level: – 60 dBm
Procedure:
1. Connect the 1/4 λ sleeve antenna to a SSG, and put the an-
tenna by the lead wire antenna (ANT2).
2. Connect REC out plug (P1) to an audio analyzer.
3. Set the [RF CHANNEL] switch (SW1) to [2].
4. Adjust RV52 on the RX BASE board so that the value of au-
dio analyzer becomes –46.7 dBV.
Adjustment Location:
to TP102 to TP51
– RX BASE BOARD (Component Side) –
RX BASE
board
1 t 2 t 3
oscilloscope
(DC range)
CH-1
RV52
RX Output Level
Adjustment
REC out plug (P1)
lead wire antenna (ANT2)
– RX BASE BOARD (Coductor Side) –
– 8 –
RX BASE
board
1/4 λ sleeve
antenna
audio
analyzer
REC out plug (P1)
SW1
[RF CHANNEL]
CT3 CT2 CT1
CH-2 CH-3
RX Frequency
Adjustment
IC1
TP51
TP102