Belson BSA-1520MP3, Service Manual

Page: 5 / 34

MODEL:BSA-1520MP3
FM AND AM RF ALIGNMENT CHART ( IF )
˗˴̇˸ˍ
28-Jul-04
Step item Input Circuit Output Circuit Tuner Adj - Adjustment
Setup Setup setting Point
Unless otherwise specified set switches as follows:
FM Function: FM
Adjust generator frequency to a center of the FM band where no FM broadcast exists
IF Connect FM IF Connect Co19 and GND FM in band Adjust for straight and
˄
Adjustment sweep output IF-OUT terminal to end T304 symmetrical S-curve
terminal to IC302 IF sweep input terminal with max.amplitude.
˅
FM Headphone jack or 87.5 MHz L303 Adjust L301 for max output
Band setup speaker terminal 108MHz Done
FM SG ANT. Headphone jack or 90.1 MHZ L302 Adjust for max.output and
ˆ
Tracking (1) Terminal 90.1 MHz, speaker terminal MONO best waveform
1kHz, +-22.5kHz dev
ˇ
Tracking (2) 106.1 MHz, 1 kHz Headphone jack or 106.1 MHz CT303 Same as above.
+-22.5 MHz dev speaker terminal
ˈ Repeat steps 3 and 4.
MW
IF Connect standard loop Connect input terminal MW in band Adjust tor max. amplitude
˄ Adjustment antenna to output ter- genescope to detector end ˧ˆ˃˅ with symmetrical 450 kHz.
minal of genescope output
˅
MW Headphone jack or 522 kHz T301 Adjust L135 for max output
Band speaker terminal 1620 kHz CT302 Adjust CT133 for max output
ˆ
Tracking (1) 612 kHz 400 kHz, Headphone jack or 612 kHz T303 Adjust for max.output and
3% mod speaker terminal best waveform
ˇ
Tracking (2) 1404 kHz 400 kHz, Headphone jack or 1404 kHz CT301 Same as above.
3% mod speaker terminal
ˈ Repeat steps 3 and 4.
TAPE SECTION
HEAD ADJUSTMENT (AZIMUTH)
10 kHz test tape (example:MTT-114N) must be used for this adjustment. Connect to VTVM or oscilloscope to the head-
phone JCK or speaker terminal Press the play button.
Adjust the azimuth by using a screw driver to maintain the maximum L & R output voltage. Adjust tape. Please secure the
azimuth position by using locking paint.
RECODING BIAS OSCILLATOR FREQUENCY ADJUSTMENT
Connect the frequency counter to of R601 two ends.
Press REC button of tape .
Adjust T201 obtain 60 kHz +-100 HZ
BSA-1520
ALIGNMENT PROCEDURE
4