Pioneer SX-750 Service Manual

I
6.2
FM
SECTION
FM
Trac(ing
1.
Connect
measuring
equipment
as shown
in
Fig.
15.
2.
Set FM
SG
to lO|Vo
modulation
(x7lkHz
deviation)
at
4OOHz
and 100dB
output.
3.
On
SX-750
front
panel,
set FM
switch
to ON,
FM
muting
to OFF
and VOLUME
control
to
minimum
position.
4. Set
TC6 to center
of turning
range.
5.
T\rne FM
SG
and
SX-Z5O
to dial
readings
of
9OMHz.
6. Adjust
T4
core
for
maximum
indication
on
Signal
meter.
7.
Adjust
T6
core for
center
of scale
indication
on
Tuning
meter.
8.
Set FM
SG
output
to 8-
10dB
and
adjust cores
of
T1,
T2, and
T3
for
maximum
indication
on
Signal
meter.
9.
Ttrne FM
SG
and
SX-250 to dial
readings
of
106MHz.
10.
Set FM
SG
output
to 100dB
and adjust
TC6
for
muimum
indication
on
Signal
meter.
11.
Set FM
SG
output to 8-10dB
and
adjust
TC1,
TC3.
TC5 and TC6 for
maximum indication
on
Signal
meter.
12.
Repeat
above
adjustment
steps
5
-
11 and
adjust
for
optimum
conditions.
13.
Tune FM
SG
and
SX-750
to
dial
readings of
90MHz.
14.
Adjust
T5
core for
maximum
indication
on
Signal
meter.
L5.
Detune
SX-750
(to
noise
only).
16.
Adjust
T6 for
center
of
scale
indication
on
Tuning
meter.
17.
Tune FM
SG
and
SX-750
to dial readings
of
98MHz.
18. Set
FM
SG
output
to
60dB and
adjust upper
core
of T7 for
maximum
reading
on AC volt-
meter.
19.
Adjust lower
core
of
T7 for
minimum
audio
frequency
output
distortion.
20.
Set
FM
SG for
100dB output
and adjust
VR1
so that
Signal
meter indicates
5 of
the scale.
AC voltmeter
Distortion
meter
FM.
SG
FM
signal
generator
Fig. 15

Pioneer SX-750 Specifications

General

Signal to Noise Ratio	75dB (MM), 90dB (line)
Tuning Range	FM, MW
Damping Factor	30
Power Output	50 watts per channel (8 ohms, 20Hz-20kHz)
Frequency Response	10Hz to 50kHz
Total Harmonic Distortion	0.3%
Input Sensitivity	2.5mV (MM), 150mV (line)
Output	150mV (line)
Speaker Load Impedance	4Ω to 16Ω