Sony TA-AX5 Service Manual

1.2.
SERVICING NOTE
1.
Pulse
Power
Supply
Board Repairing
This
set
has a
pulse power-supply
circuit which
is
quite
different
from
a conventional
power-
supply circuit.
The
pulse power-supply
directly
rectifies and smooths
the
ac
input
power
to
produce
the
higher dc voltages required in
the
power-supply
circuit.
When
servicing
this set, note
the
following.
a) To
prevent
urrwanted radiation due
to
pulse
signals in the
pulse power-supply
circuit, the
pulse power-supply
board
is
shielded
by
the
aluminum diecast
box.
b)
Take
care
that
electrolytic
capactitor which is
used after
the
rectification
of
ac
power
source
voltage
is charged even if
the
POWER
switch is
turned off.
Be
sure
to
use
a
resistor
of at least
several hundred
ohms to discharge
the capaci-
tor. Direct discharge
by means
of
lead
is
dangerous.
2. Inverter
Circuit Transistor Replacement
When any of inverter
transistors
(Q903,
Q904)
is broken, replace their transistors
together. A
pair
of transistors
with
the
same rank
is
provided
for
service field use.
Rsf.
No. Pert No.
Description
Q903, Q904
x-4866-605-l
Transistor
Ass'y,
seryice
3. Inverter
Circuit
Transformer
Replacement
The
lead
wire arrangement
for
each of T90l
and T9O2
in the inverter
circuit is shown
in Fig. A.
As the repair
parts,
T90l
and T9O2
arc formed
by
only iron
core. Thus,
if
the coil
is defective,
arange
a
new
transforners
as shown
below. Note
that the lead
lengths must
be exact.
Also
wind
the
coil
carefully.
T90l core
lPart
No.
l-543-098-001
\
l-543-tOO-OO1
7902 core
(Part
No. l-543-166-00)
(
one
turn
I
wire length:
70
mm
(2%
inches)
I
diameter :
UL 106l
AWG28
I
two tums
I
wirc
length: 70 mm
(2%
inches)
ldiameter
: UL lMl
AWG28
I
two
turns
I
wire
length
: 55 mm
(21/6inchesl
I
diameter-
:
UL t6l
AWG2B
40 mm
(
|
3Â
inches)
UL I4:'O
AWG22
two tums.
wire length:
70 mm
(2i4
inchas)
diameter
:
UL 106l
AWG28
FtC.
A

Sony TA-AX5 Specifications

General

Brand	Sony
Model	TA-AX5
Category	Amplifier
Language	English