Tuner Alignment; Receiver - JBL JSR-400 Service Manual

Dolby Pro-Logic A/V Receiver
Ò
Test Equipment Required
1) AM/FM Signal Generator
2) Digital Multimeter
FM Tuner Section
Connect the FM signal generator (FM SG) to the FM antenna a 300W
Set the receiver to the FM band.
1) Tune the FM SG to the receiver.
2) Connect the FM Multiplex stereo signal generator to the FM SG external modulation terminal.
3) Set the modulation to main 1 kHz/L+R/67.5 kHz deviation, pilot 19 kHz/6 kHz deviation.
FM SG
1 kHz 75 kHz deviation
STEP
Frequency
1 No Signal
2 No Signal
3 98 MHz 66 dBu
4 98 MHz 22 dBu
5 98 MHz 66 dBu
AM Tuner Section
1) Connect the furnished AM Loop antenna between terminals AM ANTENNA and GND.
2) Connect the AM signal generator (AM SG) tot he AM antenna terminal.
3) Tune the AM SG to the receiver.
AM SG
400Hz 30% Mod.
STEP
Frequency
1 No Signal
2 No Signal
3
4 600 kHz 22 dBu
5 1500 kHz 66 dBu
6
100dBu
7 1000 kHz
8 1000 kHz

TUNER ALIGNMENT

Tuner Frequency
Display
Level
87.5 MHz
108 MHz
98 MHz
98 MHz
98 MHz
Tuner Frequency
Display
Level
520 kHz
1720 kHz
Repeat the step 1 and 2 until both specification are correct.
600 kHz
1500 kHz
Repeat the steps 4 and 5 until maximum sensitivity is attained.
1000 kHz
v/m
83dBu
1000 kHz
v/m
terminal through a 300W
Adjustment Point
Confirm that DC 1.8 ±0.5V between VT Terminal
Confirm that DC 8.0V ±0.5V between VT
FM DET COIL
Connect the Digital Volt Meter to WA2 Adjust T4
so that adjustment value is less than ±30mV
- T4 -
S.F.R. 10K
Adjust until you turn on the "TUNED" segment in
VR302
Adjust so that the left (or right) channel output
S.F.R. 220K
becomes minimum when only the right (or left)
VR401
channel of the stereo modulator is modulated.
Adjustment Point
AM OSC COIL
Adjust until DC 1.2V ±0.03V between VT jumper
T6
CERAMIC TRIMMER
Adjust until DC 9.0V ±0.5V between VT jumper
CT2
Adjust until you turn on the "TUNED" segment in
AM ANT COIL T1
CERAMIC TRIMMER
Adjust until maximum sensitivity is attained
CT1
AM IFT COIL
Adjust until maximum sensitivity is attained
T2
S.F.R. 10K
Adjust until turn on "TUNED" segment in VFD
VR301
dummy antenna.
Adjustment Procedure
and Ground
Terminal and Ground
V.F.D.
Adjustment Procedure
and ground is attained (J37)
and ground is attained (J37)
V.F.D.
JSR-400
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