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High Frequency
6.
Set the RF Generator to 108 MHz, a modulation
of 1kHz and a deviation of 75 kHz, to provide an
input of 2 uV.
Set the dial pointer to 108 MHz.
8.
Adjust
the FM Trimmers
TC3, TC2
and TC1
in
the tuning gang to maximize the output.
9.
Repeat these high and low frequencies adjustment
alternately until maximum sensitivity is obtained.
~S
Multiplex and Stereo Separation
Multiplex
1.
Set the stereo signal generator as follows: 400 Hz
modulation
frequency,
7.5kHz
deviation
pilot,
67.5 kHz main and sub carriers. Connect its out-
put to an RF generator.
2.
Connect
the
RF
Generator
to the antenna
ter-
minal through
a dummy antenna.
3.
Connect
a VT VM,
an Oscilloscope and a Distor-
tion Meter
to the TAB
No.
107
(Left)
or 108
(Right).
4.
Set the RF Generator to the 98 MHz and an out-
put of 1 mV.
5.
Set the dial pointer to 98 MHz.
6.
Connect
the Frequency
Counter
to the TP (Test
Point) 119.
7.
— Switch off the pilot signal of Stereo Modulator.
8.
Adjust R143 so that the Frequency Counter indi-
cates 19 kHz (0 ~-50 Hz).
Stereo Separation
9.
Switch
the selector
of the Stereo
Modulator
to
Left channel modulation.
10.
Adjust R157
so that the output of the Right
channel is minimized.
11.
Switch
the
selector
of the modulator
to Right
channel modulation.
12.
Adjust
R157
so that the Left channel
is mini-
mized.
13.
Set
R157
to average,
if the separation of Right
and Left are different.
Muting Level
Note:
@No
adjustment
is necessary.
However,
if the
check ing-up is required, take the following steps.
@Keep
the muting pushbutton
out (ON) during
this adjustment procedure.
1.
Connect
a VT VM
and an oscilloscope to the out-
put signal plug.
2.
Set the RF generator to 108 MHz, a modulation of
1kHz
and
a deviation of 75 kHz, to provide an
input of
5uV.
3.
Turn
R133
counterclockwise
and
remember
the
point at which the muting ceases operating.
4.
Turn
R133
clockwise
slightly so that the output
level drops by 1 dB.
D:
Attenuate the output of the RF generator to 2 dB
from 5uV of step 2 and check that the muting is
still operating.
MIW & LW
Section
ala eo
oF 2 TO
TC?
TCE
TC9
TC8
TRF-41 MW/LW RF P.C. Board Ass'y
Fig. 9
Loop antenna
AM dummy
antenna
Oscillo-
scope
Fig. 10
Hen
Note: ( ) for LW Alignment Procedure
MW(LW) Tracking and Sensitivity
Low Frequency
1.
Connect the RF Generator to the antenna terminal
on the rear panel, set this to 600kHz
(160kHz)
with 30% modulation at 400Hz.
2.
Connect an AC VTVM and an oscilloscope to TAB
No. 107 or 108.
3.
Set the dial pointer to the 600kHz (160kHz).
4.
Adjust OSC Transformer T302 (T301) and the fer-
rite bar antenna adjusting the MW
(LW) coil to
maximize the output signal.
High Frequency
5.
Set the RF Generator to 1400kHz (350kHz) with
30% modulation at 400Hz.
6.
Set the dial pointer to 1400kHz (350kHz).
7
Adjust the trimmers TC9 (TC8) and TC7 (TC6) in
the tuning gang so that the output signal is maxi-
mized.
8.
Repeat these high and low frequencies adjustment
procedures
alternately until maximum
sensitivity
is obtained.
T-V5L
No. 2463
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