Sony MB-806A Service Manual page 37

3. Frequency characteristic check
Procedure
Step 1: Tuner [1] (Tuner unit 1) checking
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The checking procedures describe that the WRU-806A (to be
adjusted) is installed into the Tuner [1] slot on the MB-806A.
(1) Set the MB-806A as follows;
Front panel (Tuner [1])
Channel setting:
CE62 model; Group 00, 6301 channel (806.125 MHz)
CE69 model; Group 00, 6933 channel (858.125 MHz)
AU66 model; Group00, 6701 channel (799.250 MHz)
Muting: OFF
Rear panel
ATT (ANTENNA A, B) switch: 0 dB
(2) Connect the audio analyzer to the TUNER OUTPUT 1
connector via MIC amp.
(3) Connect the signal generator to the ANTENNA A IN
connector with DC cut fixture.
(4) Set the signal generator as follows:
Signal generator setting
FREQUENCY(carrier frequency):
CE62 model; 806.125 MHz
CE69 model; 858.125 MHz
AU66 model; 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 1
(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 proce-
dure (3) is set also as follows.
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100 Hz and 15 kHz modulation frequency must be set
by using the function generator.
MODULATION frequency
of signal generator
100 Hz
15 kHz
(7) Connect the signal generator to the ANTENNA B IN
connector with DC cut fixture, and perform the
procedures (4), (5) and (6).
MB-806A (CE)
WRU-806A (CE, AU)
EMF
(= _53 dBm)
TUNER OUTPUT 1 connector
output level
_0.7 ±1.0 dB
_28.5 ±2.5 dB
Step 2: Tuner [2] to Tuner [6] checking
When the WRU-806A Tuner Unit is installed in the Tuner
[2] (Tuner unit 2) to Tuner [6] (Tuner unit 6) of the MB-
806A, perform the adjustments from procedures (1) to (7)
of "Step 1. Tuner [1] (Tuner unit 1) checking" on the
respective tuner units that are installed in the MB-806A.
When performing the above described checking change the
following details as shown below, of the "Step 1. Tuner
[1] (Tuner unit 1) checking".
Tuner [1] → Tuner [2], [3], [4], [5], and [6]
TUNER OUTPUT 1 → TUNER OUTPUT 2, 3, 4, 5, and 6
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