Sony STR-AV280L - Page 10

AAV28OL STR-AV280OL
FM Discriminator Alignment 1
Setting:
TP
_9 | (NULL check)
TP (NULL check)
(secondary side)
T7201
(primary side)
T202 T201
Procedure:
1, Tune the set in the strong station-signal.
2. Adjust the black core (primary-side) of T201 for
OV reading on VOM.
Note: When replacing the ceramic filter, perform this align-
ment.
FM Discriminator Alignment 2
Setting:
distortion
meter
FM rf signal
generator
ANTENNA 762. REC OUT
terminals
Carrier frequency: 98MHz
Modulation: 400Hz, 40kHz deviation
(100%)
10uV (20dB)
Output level:
Procedure:
Adjust the white core (secondary side) of T202 for
minimim distortion.
Note: When replacing the ceramic filter, perform this align-
ment.
Repeat the secondary-side and primary-side alignments
several times.
AM SECTION
e Repeat the procedures in each adjustment
several times, and the frequency coverage and
tracking adjustments should be finally done by
the trimmer capacitors.
AM TRACKING ADJUSTMENT
Setting:
AM rf signal put the lead-wire
generator antenna close to
the
set.
vie
===
30% amplitude
modulation by REC OUT
400 Hz signal
AM FREQUENCY COVERAGE
ADJUSTMENT
TP (CV check)
Frequency Voltage at TP
display in set (CV)
531kHz 1.1V £0.2V
1,602kHz 9.0V £0.2V
Frequency Voltage at TP
display in set (CV)
1. 153kHz 1.0V £0.2V
344kHz 9.0V +0.2V
Procedure:
1. Tune the set to the SG signal.
2. Adjust for a maximum reading on VTVM.
MW
SG and set Adjustment Reading on
frequency Parts VTVM
603kHz core of T401
1,404kHz CT401
SG and set Adjustment Reading on
frequency parts VTVM
170kHz core of T405
310kHz CT403
CT401 7401
1.
2.
LW
1. |
7405 |[CT403
TP
(CV.
check) :
CT404
CT402
T4023 ae
7404
7403
450kHz T403
Adjust for a maximum reading
on VTVM.
AM IF ALIGNMENT
STR-AV280L