Electrical Adjustments; Tx Section - Sony WCS-880 Service Manual

WCS-880
Note: Tool
• 1/4 λ sleeve antenna
Production procedure:
1. Cut about 80 mm of the outer cover at the other end of an
approximately 2 meter coaxial cable (1.5D-2V or the equiva-
lent) with a BNC connector.
80 mm
2. Pull back the outer cover and fold the wire mesh over the out-
side cover.
80 mm
80 mm
3. Cover the folded back wire mesh (outer cover) with a tube (for
example, heat shrink tube) and fasten.
4. Preparation of 1.50 - 2 V coaxial cable
Mesh
4 mm 6 mm 80 cm
The WCS-880 is a wireless microphone system operating in the 800
MHz. This system comprises the transmitter unit and the receiver unit.
6
SECTION 3

ELECTRICAL ADJUSTMENTS

1. Consumption Current Check
Setting:
BNC
BNC
Procedure:
1. Connect a regulated dc power supply (1.5 V) and ampere meter.
2. Check that the value of ampere meter satisfy specified value.
Specified value: 50 mA to 60 mA
2. TX OSC (12.8 MHz) Adjustment
BNC
Setting:
BNC
Procedure:
1. Connect a frequency counter to the TP53 on TX BASE board
2. Set the [RF CHANNEL] switch (SW51) to[2].
3. Adjust CT2 on the TX BASE board so that the value of
Specified value: 12.794 ± 0.001 MHz
3. TX Frequency Confirmation
Setting:
Procedure:
1. Connect the 1/4 λ sleeve antenna to a frequency counter, and
2. Set the [RF CHANNEL] switch (SW51) to[1].
3. Confirm that the value of frequency counter satisfy specified
4. Change the [RF CHANNEL] switch (SW51) to [2].
5. Confirm that the value of frequency counter satisfy specified
6. Change the [RF CHANNEL] switch (SW51) to [3].
7. Confirm that the value of frequency counter satisfy specified
Specified values: CH-1: 863.33 MHz to 863.47 MHz
0 dBm = 1 mW, 0 dBV = 1 Vrms

TX SECTION

regulated dc
power supply
battery
terminal 3
+
mA
–
battery
terminal #
TX BASE board
TP53
Foot of VCO board
shield case
and the foot of VCO board shield case.
frequency counter becomes 12.794 MHz.
TX BASE
board
1/4 λ sleeve antenna
lead wire antenna (ANT1)
put the antenna by the lead wire antenna (ANT1).
value.
value.
value.
CH-2: 864.13 MHz to 864.27 MHz
CH-3: 864.53 MHz to 864.67 MHz
Set
frequency counter
+
–
frequency counter