Technics SU-V620 - Tone Amplifier Circuit; Headphones Jack Circuit

Before
requesting
service
for
this
unit,
check
the
chart
below
for
a
lf
you
are
in
doubt about
some
of
the
check
points,
or
if
the
possible
cause
of
the
problem
you
are
experiencing.
Some
simple
remedies
indicated
in
the
chart
do
not
solve
the
problem,
refer
to
checks
or
a
minor
adjustment
on
your
part
may
eliminate
the
pro-
the
directory
of
Authorized
Service
Centers
(enclosed
with
this
blem
and
restore
proper
operation.
unit)
to
locate
a
convenient
service
center,
or
consult
your
Technics
dealer
for
instructions.
Problem
Probable
cause(s)
Suggested
remedy
Problems
noted
at
all
times
No
sound
is
heard
when
the
|
The
power
cord
plug
is
not
completely
inserted.
*
Confirm
that
the
power
cord
plug
is
connected
power
Is
switched
ON.
completely.
Connections
to
the
speakers,
etc.
are
incomplete
|
*Check
to
be
sure
that
all
connection
wires
are
or
incorrect.
correctly
connected.
The
input
selector
setting
is
incorrect.
©
Check
to
be
sure
that
the
selection
of
the
desired
sound
source
is
made
correctly,
The
speaker
selector
is
set
incorrectly.
®
Set
it
to
the
correct
position.
The
tape
monitor
function
is
on.
®
When
listening
to
a
source
other
than
the
tape
deck
(TAPE
1
MONITOR
Indleator
is
illuminated)
(TAPE
1),
press
TAPE
1
MONITOR
so
that
the
_|
indicator
is
switched
off.
When
listening
to
stereo
One
of
the
speakers
is
connected
out
of
phase
°
Reconnect
the
speakers
maintaining
proper
polarity
sound,
the
sound
lacks
[((F}-(-),
(-)}>(4)).
[Le
(+)>(+),
(~)>(-)],
depth (i.e. thin bass, tinny
sound).
When
listening
to
stereo
The
ieft
and
right
speaker
connections,
source
©
Check
all
connections
and
correct
them
if
necessary.
sound,
the
left
and
right
connections,
or
graphic
equalizer
connections
sounds
are
reversed.
are
reversed,
A
low-pitched
noise
(“hum”
|
The
power
cord
or
a
fluorescent
light,
etc.,
isnear
|
Try
separating
this
unit
as
far
as
possible
from
the
or
“buzz”)
Is
heard.
the
connection
wires.
electric
appliance.
Sound
is
not
heard
from
The
speaker
wires
are
disconnected.
Check
and
correct
the
connections
of
the
speaker
one
of
the
speakers.
wires.
The
balance
control
is
set too
far
to
one
side.
|e
Set
so
that
sounds
are
heard
at
the
center,
between
the
speakers.
Sound
stops
during
a
The
protection
circuitry
has
functioned
because
¢Turn
the
unlt
OFF,
and,
after
determining
and
performance,
or
no
sound
the
positive
and
negative
speaker
connection
correcting
the
cause,
turn
the
unit
ON
once
again.
Is
heard
when
the
power
Is
|
wires
are
“shorted",
speakers
with
an
impedance
|
«
Use
the
speakers
of
the
proper
impedance
rating.
switched
ON.
less
than
the
indicated
rated
Impedance
of
the
amplifier
are
used.
While
using
the
remote
control
transmitter
The
remote
control
Batteries
are
incorrectly
installed,
©
Insert
the
batteries
so
that
the
positive
(+)
and
transmitter
does
not
negative
(—)
polarities
are
correct.
function.
The
remote
control
transmitter
batteries
are
*
Replace
them
with
new
batteries.
drained.
There
is
an
obstruction
between
the
remote
*
Remove
the
obstruction.
control
transmitter
and
this
unit,
The
remote
control
transmitter
is
not
correctly
*
Face
the
remote
control
transmitter
correctly
toward
facing
this
unit.
this
unit.
_
Matsushita
Electric
Industrial
Co.,
Ltd.
Central
P.O.
Box
288,
Osaka
530-91,
Japan
RQT3112-B
Printed
In
Japan
HO795u0