Measurements And Adjustments; Tuner Section Adjustments - Panasonic RX-DT30 Service Manual

, RX-DT30 1
H Measurements and Adjustments
n
TUNER SECTION
. ALIGNMENT INSTRUCTION
Set power source voltage to 12 V DC.
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Set volume control to maximum
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Set band switch to AM or FM
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Set selector switch to RADIO
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Note :
No FM STEREO alignment is required due to Tuner IC (BAl442A) is used.
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. AM-IF ALIGNMENT
SIGNAL GENERATOR or
SWEEP GENERATOR
CONNECTIONS FREQUENCY
Fashion a loop of
several turns of 455 kHz
wire and radiate a 30 % Mod.
signal into the loop at 400 Hz
ant. of receiver.
AM-RF ALIGNMENT
l
SIGNAL GENERATOR or
SWEEP GENERATOR
CONNECTIONS FREQUENCY
II
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1753 kHz
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1500 kHz
['I] Fix antenna coil with wax after completing alignment.
FM-IF ALIGNMENT
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SIGNAL GENERATOR or
SWEEP GENERATOR
CONNECTIONS FREQUENCY
Connect to test
pointm through
10.7 MHz
ceramic capacitor.
Negative side to
(Sweep)
.
test point m
FM-RF ALIGNMENT
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66.2 MHz
Connect to test
point m
through FM dummy
antenna.
109.2 MHz
Negative side to
test point m
[*2] Three output response will be present; proper tuning is the center frequency.
READ CAREFULLY BEFORE AT-TEMPTING ALIGNMENT
RADIO DIAL
SETTING
Point of non-
interference.(on/
about 6OOkHz)
c
RADIO DIAL
SETTING
Tuningcapacitor
511 kHz
fully closed.
Tuningcapacitor
fully opened.
Tune to signal
600 kHz
I ,
RADIO DIAL
SETTING
Point of non-
interference.(on/
about 90 MHz)
Variable
capacitor
fully
closed.
Variable
capacitor
fully opened.
106 MHz
Tune to signal
Set XBS switch to minimum
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Output of signal generator should be no higher than necessary
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to obtain an output reading.
INDICATOR
(ELECTRONIC ADJUSTMENT
VOLTMETER or
(Shown in Fig. 1)
OSCILLOSCOPE)
Headphone Jack
(32D)
T2(AM IFT)
abicale tfw plug as shown
in Fig.2 and then connect
tie lead wires of Me plug to
the
measuring instrument.
INDICATOR
(ELECTRONIC
ADJUSTMENT
VOLTMETER or
(Shown in Fig. 1)
OSCILLOSCOPE)
II
L4(AM OSC Coil)
CT1 -4(AM OSCTrimmer) Adjust for maximum output.
['I] LS(AM ANT Coil)
CT1 -3(AM
INDICATOR
ADJUSTMENT
(ELECTRONIC
(Shown in Fig. 1)
VOLTMETER or
OSCILLOSCOPE)
Connect vert. amp. of
scope to test point
Tl(FM 1st)
m
Negative side to test
point m.
TB(FM 2nd)
Headphone Jack
(32~)
Fabicale the plug as shown (FM OSC Coil)
L2
in Fig.2 and then connect
the lead wires of the plug to
the measuring instrument. >
CT1 -2 (FM OSC
8,
CTI-1 (FM ANT
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-3O-
REMARKS
Adjust for maximum output.
REMARKS
Adjust for maximum output.
Adjust for maximum output. Adjust L3 by
moving coil bobbin along ferrite core.
Adjust for maximum output.
ANT Trimmer)
REMARKS
Waveform is shown in Fig. 3
Waveform is shown in Fig. 4
[*2] Adjust for maximum output.
I I
Trimmer)
Trimmer)