Sony MB-806A Service Manual page 42

9. Tone squelch 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
(2) Connect the signal generator to the ANTENNA A IN
connector with DC cut fixture.
(3) 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):
32.768 kHz
(32.768 kHz must be set
by connecting Function
generator)
DEVIATION (Frequency deviation): + 1.4 kHz
(4) Turn on and off the MODULATION (modulation
frequency) of the signal generator as follows, and the
LCD indicator (Tuner [1}) changes also as follows.
MODULATION ON/OFF LCD indication of Tuner
on signal generator
ON GP/CH indication (LCD):
CE62 model; "00. 6301" appears.
CE69 model; "00. 6933" appears.
AU66 model; "00. 6701" appears.
OFF GPYCH indication (LCD):
"NO TONE" appears.
(5) Connect the signal generator to the ANTENNA B IN
connector with DC cut fixture, and perform the
procedures (3) and (4) above.
MB-806< (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 (5)
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]
10. DC +9 V OUT voltage check
Equipment and Tools
* DC voltmeter (digital multi meter)
* Metal film resistor 91 Q 2W (Part No. 1-214-609-00)
Procedure
(1) Connect the DC voltmeter to the ANTENNA A IN/DC
9 V OUT connector with 91 Q resistor as shown figure
below.
DC voltmeter
o>
NTENNA
N
MB-806A
(2) Check that DC output voltage of ANTENNA A IN/DC
9 V OUT connector is +8.6 +0.6 Vdc.
(3) Connect the DC voltmeter to the ANTENNA B IN/DC
9 V OUT connector with 91 Q resistor.
(4) Check that DC output voltage of ANTENNA B IN/DC
9 V OUT connector is +8.6 +0.6 Vdc.
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