Teac A-7300RX - Page 28

11.
TROUBLE-SHOOTING-2
MALFUNCTION
—
Transport
inoperative
(Capstan
only
rotates)
...
—
Cannot
select
PAUSE
..
—
Amplifier
inoperative
..
—
Playback
audio
intermittent
or
absent
a)
Both
channels
inoperative
........----+++-
(SOURCE
OK)
b)
R-Ch
or
L-Ch
inoperative
......------
55+
—
Playback
sound
is
not
clear...
....-
+--+
eee
+0
_
VU
Meter
inoperative
in
TAPE
Monitor
mode
....
(sound
is
normal)
—
Hum
in
playback
signal
.
—
Intermittent
or
absence
of
audio
at
PHONES
jack
. . .
—
LINE
IN
signal
is
not
applied
to
SOURCE
.......
(Playback
normal)
—
Will
not
Record
......
—
Recorded
sound
not
clear
—
Inoperative
MIC
Recording
(LINE
IN
signal
normal)
—
Hum
in
Recording
signal
POSSIBLE SOURCE OF TROUBLE
Specified
8V
DC
present
on
the
STABILIZER
UNIT
J21
Pins
#5,
#6
Defective STABILIZER UNIT
Specified
8V
DC
not
present
on
the
STABILIZER
UNIT
J21
Pins #5, #6
Faulty D14~D17 or fuse F2 (2A)
Defective CONTROL UNIT
Voltage
not
present
on
P151
at
Pin
#10
or
#11
(To
ampl.
connector)
Fuse F1 (2A), F4 (0.5A) burned out
Voltage present on P151 at Pins #10 or #11
Defective Q601, Q602, Q603
(on AMPL. STABILIZER UNIT)
Defective
Q207,
Q208,
Q209
(on
PLAY
EQ
AMPL.
UNIT)
or associated parts
SOURCE also inoperative
Defective
Q301
(on
METER
PHONE
AMPL.
UNIT)
or
associated parts
SOURCE Monitor function normal
Defective
Q201,
Q203,
Q205,
Q207
(on
PLAY
EQ
AMPL.
UNIT)
Q251,
Q253
(on
PLAY
LINE
AMPL.
UNIT)
or
associated parts
High
Freq.
weak.....
Dirty
head,
incorrect
Adj.
of
VR201/
203
(on
PLAY
EQ
AMPL.
UNIT)
Sound
distorted
.....
Defective
Q201,
Q203,
Q205
(on
(PLAY EQ AMPL. UNIT)
Defective
Q306
(on
METER
PHONE
AMPL.
UNIT)
oras-
sociated
parts,
Faulty
VU
Meter
ass’y
Defective Playback head
Defective
Q303, Q305,
Q307
(on
METER
PHONE
AMPL.
UNIT)
or
associated
parts
Defective Q405, Q406 (On MIC MIXING AMPL. UNT)
Q451, Q453 (on REC LINE AMPL. UNIT), etc.
No
Erase
.....
Defective
K551,
Q551~554,
T551
(on
BAS
OSC
UNIT)
Erase
normal.....
Sound
normal
at
SOURCE
Defective
Q507,
Q509
(on
REC
AML.
UNIT)
Dirty or defective record head
Dirty record head, incorrect Bias Adj. or
Defective Q505 (on REC AMPL. UNIT)
Defective Q401~Q404 (on MIC MIXING AMPL. UNT)),
etc.
Defective
Record
head
or
P702
connector
loose
or
hacis
magnetized
29