Sony MB-806A Service Manual page 40

7. Muting level check
Procedure
Step 1: Tuner | 1| (Tuner unit 1) checking
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: ON (Normal mode)
Rear panel
ATT (ANTENNA A, B) switch: 0 dB
Connect the signal generator to the ANTENNA A IN
connector with DC cut fixture.
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 dBuUVEMF
(= —53 dBm)
MODULATION (Modulation frequency): 1 kHz
DEVIATION (Frequency deviation): +5 kHz
Check that RF Indicator LED lights (green) and "NO
TONE" message appears on LCD (Tuner (1]).
Change the RF OUTPUT (output level) of the signal
generator as shown below.
RF OUTPUT (output level): 15 dBUVEmMF
= —98 dBm)
Check that RF Indicator LED goes off (green) and
(2
~
(3
~
(4
~~
(5
~
(6
a
"NO TONE" message disappears on LCD (Tuner [1]}).
(7
—
Increase gradually the RF OUTPUT (output level) of
the signal generator. Check that RF OUTPUT (output
level) is 25 dBuVemF +5 dB at when RF Indicator
lights (green LED) and "NO TONE" message appears
on LCD (Tuner [1]).
a
AF
RFa/o
a 8 [pel
]o
FF indicator lights.
MB-806A (CE)
WRU-g06A (CE, AU)
(8) Connect the signal generator to the ANTENNA B IN
connector with DC cut fixture, and perform the
procedures (3) through (7) above.
(9) Set the channel setting (Tuner [1}) and FREQUENCY
(carrier frequency) of the signal generator as shown ()
and ® below. .
Perform the procedures (1) to (8) above, for each
channel setting (® and @)).
@ Channel setting:
CE62 model: Group 00, 6217 channel (800.125 MHz)
CE69 model: Group 00, 6901 channel (854.125 MHz)
AU66 model: Group 00, 6601 channel (792.250 MHz)
Signal generator setting:
FREQUENCY (Carrier frequency)
CE62 model: 800.125 MHz
CE69 model: 854.125 MHz
AU66 model: 792.250 MHz
® Channel setting: '
CE62 model: Group 00, 6363 channel (813.875 MHz)
CE69 model: Group 00, 6964 channel (862.000 MHz)
AU66 model: Group 00, 6751 channel (805.500 MHz)
Signal generator setting:
FREQUENCY (Carrier frequency):
CE62 model: 813.875 MHz
CE69 model: 862.000 MHz
AU66 model: 805.500 MHz
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 (4)
of "Step 1. Tuner (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]
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