Sanyo PLUS T35 - FM Tuning Meter and MPX Adjustments; FM Tuning Meter Center 0 Adjustment (Primary); FM Tuning Meter Center 0 Adjustment (Secondary); FM MPX Adjustment

FM
TUNING
METER
CENTER
“0”
ADJUSTMENT
(PRIMARY)
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8
—
Turn off quartz switch of the set.
Set
FM
SG
to
98.000
MHz,
1
kHz,
75
kHz
dev.
output
65
dB.
Set
the
output
of
FM
SG
to
OFF
(less
than
—20
dB),
and
turn
7202
until
the
display
of
DVTVM
connected
between
TP-4
and
TP-5
becomes
within
+10
mV.
Set the output of FM SG to ON (65 dB), and attain
finetuning
with
the
tuning
knob
so
that
the
broadcast
may
be
received
while
the
display
of
DVTVM
is
within
+10mV.
Turn
1307
until
the
waveform
distortion
of
the
oscil-
foscope
connected
between
TP-12
(hot-left),
TP-13
({hot-right)
and
TP-11
(earth)
becomes
the
minimum.
At
this
time,
keep
the
output
of
FM
SG
at
MONO
position.
Repeat adjustment steps (3) thru (5).
At
minimum
distortion
point,
fine-adjust
T201
until
the
waveform
distortion
of
the
oscilloscope
reaches
the
minimum
again.
(This
adjustment
requires
only
a
slight
rotation
of
the
core
of
T201.)
Attempt
adjustment
steps
(3)
thru
(7)
once
again.
NOTE.
lf
the
core
is
turned
too
much
in
step
(7),
the
V-curve
may
be
deviated
excessively,
so
that
the
practical
sensitivity
of
the
set
may
be
lowered.
Hence
perform
fine-adjustment
of
T201
with
care.
FM
TUNING
METER
CENTER
“0”
ADJUST-
MENT
(SECONDARY)
(1)
(2)
(3)
(4)
(5)
Connect
frequency
counter
between
TP-16
(hot)
and
TP-17
(earth).
Set
the
output
of
FM
SG
to
ON
(65
dB),
adjust
SG
frequency
to
98.000
MHz,
fine-tune
with
tuning
knob
so
that
the
counter
output
becomes
108.700
MHz.
Turn
T202
until
the
display
of
DVTVM
becomes
with-
in
+10
mV.
Detach
the
counter,
and
fine-tune
with
tuning
knob
so
that
the
broadcast
may
be
received
while
the
display
of
DVTVM
is
within
+10
mV.
Turn
on
quartz
switch,
and
turn
T203
until
the
wave-
form
distortion
of
the
oscilloscope
becomes
the
minimum.
NOTE
@ Use iHF filter of high quality characteristics.
@
Carry
out
“0”
meter
adjustment
again
when
the
FM
front
end
or
FM
IF
circuit
is
repaired
or
adjusted.
FM MPX ADJUSTMENT
1.
2.
4.
(1)
(2)
(3)
Set SVR (R325, R327 — 500K ohms, balanced) in the
central position.
Feed modulated input into FM SG through stereo
modulator.
* Modulation frequency is 1 kHz.
Pilot signal 6.75 kHz dev.
(19 kHz) (9% mod.)
Stereo signal 68.25 kHz dev.
(98 MHz) L+R (91% mod.)
NOTE
The method of taking modulation differs from one
instrument to another. Be familiarized with the handling
method of the instrument.
75 kHz dev.
(100% mod.)
. Place output signal switch of stereo modulator in MAIN
(L + R) position, turn the dial scale of the set to 98 MHz,
and tune in to FM SG. *Output of FM SG is 60 cB.
Adjustment of 19 kHz (VCO)
Place muting switch of the set in LEVEL 1 position,
and selector switch in FM AUTO position.
Connect frequency counter between TP-8 (hot) and
TP-11 (earth).
Cut the output of stereo modulator to eliminate
modulation, and turn SVR (R345, 10K ohms, bal-
lanced) until the counter display becomes within
76,000 kHz +76Hz.
NOTE
e By turning SVR (semivariable resistor), the level of
output (counter input) varies. When the resistance is
decreased, if the input level of the counter is too
small to produce display in the counter, raise the
input sensitivity of the instrument.
@ Start VCO adjustment when the state is thermally
stabilized in about 10 seconds after lighting of the
stereo pilot lamp.
@ To eliminate modulation means to turn off PILOT
and MAIN & SUB of the output signal switch.
@ Use instruments of high input impedance as far as
possible.
@ Keep the lead wires connected between the set and
instruments as short as possible.
If hum may be induced, use a hum cut filter.
DVTVM
Gesu —Te)
OuT PUT
(THe FILTER, FM ANT SET {100K OHM)
300 n /(300 a?)