Sony WCS999 - Wireless Camcorder Microphone, Service Manual

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RX SECTION
1. Consumption Current Check
Setting:
Procedure:
1. Connect a regulated dc power supply (1.5 V) and ampere meter.
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:
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 a digital voltmeter to TP51 and TP102 on the RX
BASE board.
3. Connect REC out plug (P1) to an oscilloscope.
4. Set the [RF CHANNEL] switch (SW1) to [1] .
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.
8. Change the
[RF CHANNEL]
switch (SW1) to
[2]
.
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.
– 7 – – 8 –
+
–
regulated dc
power supply
mA
Set
battery
terminal
#
battery
terminal
3
3. TX Output Level Confirmation
Setting:
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:
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:
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:
3. RX Output Level Adjustment
Setting:
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:
– TX BASE BOARD –
(Component Side)
MIC jack
(J1)
1
t
2
t
3
SW51
[RF CHANNEL]
RV3 CH-3
RV1 CH-1
RV2 CH-2
TX Modulation
Sensitivity Adjustment
RV51
TX Output Level
Adjustment
CT1
VCO Voltage
Adjustment
lead wire antenna (ANT1)
–VCO BOARD –
shield case
CP52
audio
analyzer
AF OSC
Frequency: 1 kHz
Output level: –50 dBV
+
–
MIC jack (J1)
TX BASE
board
receiver
unit
lead wire antenna (ANT1)
REC out plug
(P1)
spectrum analyzer
more than 1 GHz
lead wire antenna (ANT1)
1/4
λ
sleeve antenna
TX BASE
board
FM RF SSG
Carrier frequency: 912.85 MHz
Modulation: 1 kHz,
±
2 0 kHz deviation
Output level: – 60 dB m
REC out plug (P1)
RX BASE
board
lead wire
antenna (ANT1)
1/4
λ
sleeve
antenna
+
–
digital voltmeter
to TP102
to TP51
oscilloscope
(DC range)
FM RF SSG
Carrier frequency: 913.75 MHz
Modulation: 1 kHz,
±
2 0 kHz deviation
Output level: – 60 dB m
audio
analyzer
REC out plug (P1)
RX BASE
board
lead wire
antenna (ANT1)
1/4
λ
sleeve
antenna
– RX BASE BOARD (Component Side) –
1
t
2
t
3
SW1
[RF CHANNEL]
CT3
CH-1
CT2
CH-2
CT1
CH-3
RX Frequency
Adjustment
RV52
RX Output Level
Adjustment
lead wire antenna (ANT2)
+
–
digital voltmeter
Set
CP52
shield case
TP102
IC1
TP51
– RX BASE BOARD (Coductor Side) –