Sony WRR-800A Service Manual page 25

3. Frequency characteristic check
Procedure
(1) Set the WRR-800A as follows;
Channel setting: Group 00, 6701 channel
(799.250 MHz)
VOL. control: MAX
Muting: OFF
(2) Connect the audio analyzer to the TUNER OUTPUT
connector via MIC amp.
(3) Connect the signal generator to the ANTENNA A IN
connector.
(4) Set the signal generator as follows:
Signal generator setting
FREQUENCY (Carrier frequency): 799.250 MHz
RF OUTPUT (Output level): 60 dBuV
MODULATION (Modulation frequency): 1 kHz
DEVIATION (Frequency deviation): ± 12 kHz
(5) Read the output level of the TUNER OUTPUT
connector (indication of the audio analyzer). This level
is specified to be 0 dB.
(6) Change the MODULATION (modulation frequency)
of the signal generator as follows, and check the output
level with respect to the output level under the
procedure (5) is set also as follows.
n
100 Hz, 10 kHz and 15 kHz modulation frequency
must be set by using the function generator.
MODULATION frequency
of signal generator
100 Hz
10 kHz
15 kHz
(7) Connect the signal generator to the ANTENNA B IN
connector, and perform the procedures (4), (5) and (6).
WRR-800A
EMF
(= _53 dBm)
TUNER OUTPUT connector
output level
0 ±2.0 dB
_20 ±2.0 dB
_28 ±2.5 dB
4. Distortion ratio check
Procedure
(1) Set the WRR-800A as follows;
Channel setting: Group 00, 6701 channel
(799.250 MHz)
VOL. control: MAX
Muting: OFF
(2) Connect the audio analyzer to the TUNER OUTPUT
connector via MIC amp.
(3) Connect the signal generator to the ANTENNA A IN
connector.
(4) Set the signal generator as follows:
Signal generator setting
FREQUENCY (Carrier frequency): 799.250 MHz
RF OUTPUT (Output level): 60 dBuV
MODULATION (Modulation frequency): 1 kHz
DEVIATION (Frequency deviation): ± 40 kHz
(5) Set the audio analyzer to the distortion mode, and
check that the distortion ratio is less than 0.8 %.
(6) Change the MODULATION (modulation frequency)
of the signal generator as shown below.
MODULATION (modulation frequency): 10 kHz
(Note: 10 kHz modulation frequency must be set by
using the function generator.)
Check that the distortion ratio is less than 3 %.
(7) Connect the signal generator to the ANTENNA B IN
connector, and perform the procedures (4) through (6)
above.
(8) Set the channel setting and FREQUENCY (carrier
frequency) of the signal generator as shown 1 and 2
below.
Perform the procedures (1) to (7) above, for each
channel setting (1 and 2).
1 Channel setting:
Signal generator setting:
FREQUENCY (carrier frequency); 792.250 MHz
2 Channel setting:
Signal generator setting:
FREQUENCY (carrier frequency); 805.500 MHz
EMF
(= _53 dBm)
Group 00, 6601 channel
(792.250 MHz)
Group 00, 6751 channel
(805.500 MHz)
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