Service manual
MZ
80K
I
• Trouble Shooting Chart
Problem 1: Even if
the
play
button
is
pushed, neither motor
rotales
nor
tape
moves.
Check
for
motor
~
Electronic
governor J
motor
defective.
voltage:
see
No
if
there is
+12V
t-----
r-1
Switch
defective J
between
M+
and
M-.
Is voltage at the
switch
N~
(inter·locked
with
the
f--
play
button)
in
high level?
Check
for
vOlt~
at
cheak
point
4
Ok
(SENSE):
it
must
be
OV
with
switch
on and
+5V
with
switch
off.
Problem 2: Record (SAVE) operation
of
program
is
impossible.
No
I
rI
Switch
defective.
See
if
the
switch
SW3001
No
surely gets
in
action
~
Check
for
CPU board. I
when the record
button
f-
is
pushed.
+5V
must
be
Ok
;--<
I--
No
present
at
check
point
Does there come
N~
SW3001 defective:
@.
any signal
from
I-
Ok
check
pOint@?
Is
there
any
check
for
R3002.
ok"
signal present
r-
at
the
base
of
Q3001.
Is
there
any
signal
present
at
the
Ok
record/playback
head.
Problem 3: Playback (LOAD)
of
program
is
impossible,
or
error
is
caused.
O~
Make
su~e.of
the
tape I
I
start
position.
J
r-
D
-
o
-
e
-
s
-n-o-rm-a-I--'
r-C-h-e-c-k-f-o-r
-p-o-we-r-s-up-p-I-y"""
waveform
r-
N~
+5V
of
CPU board.
arise
at
pin
And
check
for
plug
and
@?
cable
(6
pins).
U Check
for
power
l-
No
1
supply
+5V.
I
The
waveform
is
not
normal
with
much
noises,
or
no
waveform develops.
Ok
No
Check
for
IC3001,
Check
for
l_
each voltage. I
r--'
each resistor and
SW3001.
Check
for
+12V
power
supply
circuit
(for
motor
in
tape recorder) and CPU
board.
Check
for
+5V
input
voltage I
and
R3024.
Of{
Record/playback
I
head defective.
t--
Poor
contact
of
SW3001.
Check
for
Q3001 and Q3002.
No
Is voltage applied
to
the
erase
head?
Ok
Doesn't the
erase
,.........
head operate because
of
SW3001
in
trouble?
output
voltage
waveform
h1
Check
for
the
size
of
~
Ok
of
Q3003.
Much
noises
-22-
...........
The voltage
is
too
low.
Check
for
around
Q3003.
Azimuth
adjustment
of
the record/playback head
is
improper.