Sony MB-806A Service Manual page 36

3. Frequency characteristic 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 [4])
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 dBUVEMF
(= —53 dBm)
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.
100 Hz and 15 kHz modulation frequency must be set
by using the function generator.
MODULATION frequency TUNER OUTPUT 1 connector
of signal generator output level
100 Hz -0.7 +1.0 dB
15 kHz —28.5 +2.5 dB
(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)
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 — Tuner [2], [3], [4], [5], and [6]
TUNER OUTPUT 1 > TUNER OUTPUT 2, 3, 4, 5, and 6
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