Teac A-2340 User manual

A-2340
4CHANNEL
SIMUL-SYNC
STEREO
TAPE
DECK
SERVICE
MANUAL
TEAC
CORPORATION
=
'
"970
JAE
gerry
op
wee
SALES
OFFICE:
SHINJUKU BUILDING
ee:
CALIFORNIA
90640
Bee
es
Mon
Ses
OP
ron
nate
eR
EUROPEAN
DISTRIBUTOR:
TEAC
EUROPE
N.Y.
TEAC
HONGKONG
LIMITED
ROOM
NO.
1105
KABELWEG
45-47,
AMSTERDAM-W.
2
MAIN
OFFICE:
MELBOURNE
PLAZA,
33
QUEEN'S
ROAD
C.
,
,
HONG
KONG
HOLLAND
MT2340E100
PRINTED
IN
JAPAN
472E1°S-0050

1.GENERAL
DESCRIPTION
The
TEAC
A-2340
is
a
semi-professional
tape
deck
capable
of
simul-sync
recording,
four
channel,
stereophonic
and
mono-
phonic
recording
and
playback.
It
offers
operating
speeds
of
7~1/2ips
and
3-3/4ips.
This
service
manual
provides
adjustment
and
alignment
pro-
cedures,
schematic
diagrams
and
parts
replacement
informa-
tion
and
the
proper
procedures
for
obtaining
necessary
repair
parts.
If
adjustments
or
repair
procedures
are
not
clear
or
seem
difficult
to
accomplish
or
should
you
desire
more
detailed
technical
information,
please
contact
your
nearest
TEAC
dealer,
TEAC
Corporation
or
affiliated
corporations,
ad-
dress's
of
which
are
printed
in
this
manual.
INDEX
1.
GENERAL
DESCRIPTION
2.
SERVICE
DATA
3.
EQUIPMENT
REQUIRED
4.
PARTIAL
DISASSEMBLY
5.
HEAD
ALIGNMENT
-MECHANICAL-
6.
MEASUREMENT
AND
ADJUSTMENT
-MECHANICAL-
7.
MEASUREMENT
AND
ADJUSTMENT
-ELECTRICAL-
8.
PREVENTIVE
MAINTENANCE
9.
TROUBLE
SHOOTING
10.
PACKING
FOR
SHIPMENT
SCHEMATIC
DIAGRAMS
PRINTED
CIRCUIT
BOARD
AND
PARTS
LIST
EXPLODED
VIEW
AND
PARTS
LIST
MANUAL
CHANGES

MECHANICAL
TYPE:
HEADS:
REEL
SIZE:
TAPE
WIDTH:
TAPE
SPEED:
MOTORS:
WOW AND
FLUTTER:
FAST
WINDING
TIME:
OPERATING
POSITION:
POWER
REQUIREMENTS:
WEIGHT:
20%,
19
(410mm)
7546
(440mm)
2.
SERVICE
DATA
Four
track
4
channel
stereophonic
Four
track
2
channel
stereophonic
Four
track
1
channel
monophonic
Three:
Erase
(Ferrite),
Record,
Playback
(Permalloy)
7"
maximum
NAB
reel
Standard
1/4
inch
tape
7-1/2ips
and
3-3/4ips
Two
6-pole
eddy
current
motors
for
reel
drive.
4/8
pole
hysteresis
synchronous
capstan
motor.
0.12%
at
7-1/2ips
0.15%
at
3-3/4ips
Wow
and
flutter
measured
according
to
weighted
NAB
standard
using
TEAC
flutter
free
tape.
Approx.
90
seconds
or
less
for
1,200
feet.
Horizontal
and
vertical
100/117/200/220/240
V
Ac
50/60Hz
140W
44
lbs
(20
kg)
net.
20
{326mm)
{508mm)
(170mm)
Pnenee,

ELECTRICAL
TRANSISTORS:
DIODES:
FREQUENCY
RESPONSE:
INPUT:
OUTPUT:
SIGNAL
TO
NOISE
RATIO:
BIAS
FREQUENCY:
CROSSTALK
REJECTION:
CHANNEL
SEPARATION:
ERASE
EFFICIENCY:
2SC1000
(BL)
x
2
2SC693(GU)
x
4
2SA666I(S)
x
2
2SC644(T)
x
2
2SC828(S)
x
10
2SC971
x
2
2SC536(F)
x
2
FR2-06
x
4
FR2-10
x
4
7-1/2ips
40Hzv18kHz
+3dB
3-3/4ips
50Hzv10kHz
+3dB
MIC:
0O.3mV/10k2
LINE:
0.1V/100k&
LINE:
approx.
0.3V/10kQ
or
more
HEADPHONE:
0.
3mW/82
7-1/2ips
48dB
or
higher
3-3/4ips
46dB
or
higher
at
playback
100*5kHz
push-pull
oscillator
35dB
or
more
adjacent
track
at
100Hz
45dB
or
more
channel
to
channel
at
1kHz
60dB
or
more
at
7-1/2ips
NOTE
As
a
result
of
continuing
changes
and
improvements
during
the
production
run,
minor
differences
may
be
found
between
early
and
later
machines.
Refer
to
manual
change
sheets
for
infor-
mation
concerning
modifications.

3.
EQUIPMENT
REQUIRED
FOR
MECHANICAL
MEASUREMENT
SPRING
SCALE:
Ov4kg
(08
lbs)
#5086025000
0%300¢g(0V10
oz)
#5086026000
TEST
TAPE:
TEAC
YIT-2003
(7-1/2ips)
TEAC
YTT-2002
(3-3/4ips)
FLUTTER
METER:
Meguro
Model
MK665B
(preferred)
or
Sentinel
FL-3D-1
DIGITAL
FREQ.
COUNTER:
Capable
of
0
to
5kHz
indication
TOOLS:
General,
2mm
nut
driver
#5086014000,
Hex
head,
Allen
wrench
#5086021000
ee
ce
Fig.
3-1
Spring
Scale,
Allen
Wrench
and
TEAC
Test
Tape
FOR
ELECTRICAL
MEASUREMENT
TEST
TAPE:
TEAC
YTT-1003
for
7-1/2ips
TEAC
YTT-1002
for
3-3/4ips
SCOTCH
203
and
150
for
test
recording
EMPTY
REEL:
TEAC
RE-702
(2"
hub)
TEAC
RE-701
(4"
hub)
TEST
SET:
|
TEAC
M-826A
test
set
BAND
PASS
FILTER:
TEAC
M-206A(1kHz)
VTIVM:
hp
model
4302B
or
equivalent
RESISTOR:
Non
inductive
type
8
ohm/1W
OSCILLOSCOPE:
General
purpose
NOTE
Use
of
the
TEAC
M-826A
test
set
is
recommendid.
This
set
incorporates
an
AC
VIVM,
Audio
Oscil—
lator,
Channel
Selecting
switch,
Variable
At-
tenuator,
Monitor
Speaker
and
Cables.
TEAC
M-826A
measures
the
RMS
value
of
the
Volt-
peau
icessc
oe
age(O
dB
=
0.775
V).
Characteristics
of
thi:
Fig.
3-2
TEAC
M-826A
test
set
are
similar
to
the
standard
VU-meter.

4.PARTIAL
DISASSEMBLY
R-9
R-2
R-1
LEFT REEL
MOTOR
R-3
CAPSTAN
SOLENOID
CAPSTAN
MOTOR
CAPSTAN
FLYWHEEL
M-0236
—REAR—
Tape
Transport
Parts
Location
REMOVING
WOODEN
SIDES
AND
REAR
PANEL
See
illustration
for
complete
disassembly
instructions.
1
as
ete
Hi
SOU
rh
AWA
!
AUN
Wood
Sides
Rear
Panel
and
Bottom
Plate
All
amplifier
checks
and
adjustments
can
be
made
from
the
bottom
with
the
plate
removed.
These
adjustments
should
be
performed
by
experienced
technicians,
and
then
only
when
going
through
the
complete
test
and
check
pro-
cedures
on
the
unit
which
is
being
tested.
|
{
|
.
:

HEAD
REPLACEMENT
CAUTION
Power
to
the
unit
must
be
switched
off
when
removing
the
heads,
this
will
prevent
transient
pulses
from
passing
through
the
heads
causing
strong
magnetization
or
damage
to
the
delicate
windings.
After
head
replacement,
thorough
demagnetization
is
recommended.
NOTE
The
heads
of
the
A-2340
can
be
changed
either
as
a
complete
assembly
or
individually
as
required.
HEAD
ASSEMBLY
REPLACEMENT
To
change
the
head
assembly
as
a
unit,
remove
the
two
mounting
screws,
(one
on
each
end).
Note
the
positions
of
the
wires
on
the
circuit
board
before
unsoldering.
Solder
the
wires
of
the
new
assembly
in
exactly
the
same
positions.
w-olae
Fig.
4-1
Head
Assy
INDIVIDUAL
HEAD
REPLACEMENT
We
To
replace
a
single
head,
a
special
2mm
nut
driver
is
required.
Remove
the
two
nuts
on
the
defective
head
through
the
access
hole
provided,
this
releases
the
head
from
the
mounting
plate.
Note
the
position
of
the
wires
on
the
circuit
board.
Connect
the
new
head
in
the
same
manner.
Replace
the
nuts
securing
the
new
head
to
the
plate,
perform
head
alignment
before
operation.
Head
installation
mounting
provides
for
left
or
right
positioning.
After
in-
stalling
heads,
determine
proper
posi-
tion
while
recording
or
playing
back
a
tape.
INDIVIDUAL
4CH
HEADS
Fig.
4-2
Individual
Heats

REMOVAL
OF
REMOVAL
OF
Te
2.
CAPSTAN
MOTOR
.
Remove
the
three
screws
hold-
ing
the
capstan
motor.
.
Unsolder
the
six
wire
connect-
ing
the
capstan
motor.
.
Remove
the
four
screws
holding
the
capstan
motor.
-
Loosen
the
two
set
screws
(hex
head)
in
pulley
and
lift
off
pulley.
M-o1at
Fig.
4-3
Capstan
Motor
Removal
CAPSTAN
ASSY
Unscrew
capstan
cover
(front
panel).
Remove
two
screws
from
rear
bracket,
allow
bracket
to
drop
toward
floor
of
case.
Remove
capstan
belt.
Loosen
two
screws
in
capstan
assy
flywheel.
Remove
flywheel.
Remove
three
screws
in
capstan
assy.
.
Gently
move
capstan
assy
up
and
down
until
it
slides
out
of
panel.
NOTE
A
clearance
of
0.01"
must
main-
tained
between
the
flywheel
and
capstan
assembly.
Fig.
4-4
Capstan
Assy
Renoval

REMOVAL
OF
TENSION
ARMS
LEFT
&
RIGHT
See
illustration
for
complete
disassembly
instructions.
IMPORTANT
After
reassembly
check
clearance
to
ascertain
that
arm
moves
freely
and
is
not
binding.
REMOVAL
OF
REEL
MOTOR
ASSY
1.
Loosen
2
hex
screws
in
brake
drum,
lift
off
brake
drum.
2.
Remove
3
screws
securing
the
brake
assembly
to
the
motor.
3.
Remove
reel
turntable,
remove
4
screws
securing
motor
to
front
panel.
NOTE
Reel
motor
assemblies
are
mirror
images
of
each
other,
these
as-
semblies
are
not
interchangeable.
Fig.
4-5
Reel
Motor
Removal

5.HEAD
ALIGNMENT
—MECHANICAL—
NOTE
Head
alignment
is
adjusted
at
the
factory
to
very
critical
tolerances.
Normally
HEAD
ASSEMBLY
replacement
will
require
only
minor
alignment
or
adjustments.
Complete
readjustment
should
only
be
necessary
after
an
in-
dividual
head
is
replaced.
The
adjustments
are
made
as
follows:
ERASE
HEAD
SECTION
The
erase
head
pole
should
be
above
the
edge
of
a
threaded
tape
by
the
width
of
heavy
pencil
line.
RECORD
HEAD
SECTION
The
record
head
pole
should
be
above
the
edge
of
a
threaded
tape
by
the
width
of
a
thin
pencil
line.
PLAYBACK
HEAD
The
pole
of
the
playback
head
should
be
even
with
the
top
of
a
threaded
tape.
@P
&
AZIMUTH
ADJ.
SCREW
@%
HEIGHT
ADJ.
SCREW
ERASE
RECORD
PLAY
BACK
Fig.
5-1
Head
Alignment
and
Adjustable
Screws.
NOTE
Azimuth
adjustments
are
given
in
the
section
on
MEASUREMENTS
and
ADJUSTMENTS
-ELECTRICAL-.

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D-0738

6.MEASUREMENT
AND
ADJUSTMENT
—-MECHANICAL—
The
TEAC
A-2340
uses
a
highly
reliable
three
motor
drive
system
and
should
require
a
minimum
of
mechanical
maintenance
or
ad-
justment.
These
adjustments
are
made
at
the
factory.
Readjustment
should
only
be
required
after
many
hours
of
operation
or
component
re-
placement.
PINCH
ROLLER
PRESSURE
sSsssSsSSSSSSSFFFFSSSSSSSSSSSSSSSFFSeSee
NOTE
Pinch
roller
pressure
is
supplied
by
the
pinch
roller
spring
arm
and
it
is
most
important
that
the
solenoid
plunger
be
fully
bottomed
before
taking
pressure
measurement.
Procedure
for
Check
and
Adjustment
1.
Load
tape
or
block
the
shut-off
arm
in
the
ON
position.
2.
Attach
a
suitable
spring
scale
to
the
pinch
roller
shaft.
3.
Place
the
unit
in
the
PLAY
mode
(mm),
and
holding
the
spring
scale
as
illustrated,
slowly
draw
it
away
from
the
pinch
roller.
4.
Do
not
allow
the
string
to
rub
against
the
pinch
roller.
5.
Note
the
reading
on
the
spring
scale
at
the
instant
the
pinch
roller
stops
rotating.
6.
The
scale
should
indicate
2.1%2.3
kg.
Optimum
value
is
2.2
kg.
7.
If
adjustment
is
necessary,
loosen
the
three
screws
on
the
cap~
stan
solenoid
and
position
the
solenoid
for
optimum
pressure.
8.
Adjust
solenoid
limit
position
so
that
the
gap
between
capstan
shaft
and
pinch
roller
is
approximately
7mm
when
solenoid
is
not
actuated.
Limit
is
adjusted
by
loosening
the
mounting
screw
(A),
mount
slot
is
elongated,
slide
limit
until
proper
gap
is
obtained.
CAPSTAN
CAPSTAN
SOLENOID
CAPSTAN
SOLENOID
LIMIT
PINCHROLLER
—
-
a
MOUNTING
SCREW
(A)
a
aba
wie?
D-H-13
™
“a
REPOSITION
SOLENOID
TO
OBTAIN
OPTIMUM
TENSION
Fig.
6-1
Pressure
Measurement
-Pinch
Roller-

TORQUE
ADJUSTMENT
PROCEDURE
IMPORTANT
Be
sure
the
full
required
line
voltage
is
applied
and
that
the
unit
is
set
to
the
proper
line
frequency.
1.
Measure
the
back
tension
of
the
left
reel
motor
and
the
take-up
torque
of
the
right
reel
motor.
2.
Adjust
R-1
(502)
if
measurement
value
of
right
or
left
reel
motor
exceeds
the
specified
limits.
(Coarse
adjustment)
3.
After
adjusting
R-l,
adjust
R-2
to
bring
back
tension
and
take-up
torque
to
exact
specified
limits.
NOTE
Adjustments
will
interact.
Several
adjustments
may
be
<
required
to
bring
both
motors
within
specifications.
R9
BRAKE
SOLENOID
(FIXED)
R2
TAKE-UP
TORQUE
Rl
BALANCE
R3
FAST
WIND
BACK
TENSION
Fig.
6-2
Adjustable
Parts
Location
Fig.
6-3
Torque
Measurement

TORQUE
MEASUREMENT
PROCEDURE
BACK
TENSION
1.
2.
3.
Load
tape
or
block
the
shut-off
arm
in
the
ON
position.
Place
an
empty
7"
reel
with
a
2"
diameter
hub
on
left
reel
table.
Rotate
the
reel
and
wind
several
turns
of
string
around
the
hub.
Attach
spring
scale
to
string.
Place
the
unit
in
the
(
m-)
play
mode.
Pull
the
scale
away
from
the
reel
against
the
motor
torque,
with
a
steady
smooth
motion.
Note
the
scale
reading
while
it
is
in
steady
motion.
.
Make
sure
the
string
does
not
rub
against
the
reel
flanges.
The
reading
should
be
approximately
180%220g-cm(2.813.1
oz-inch).
TAKE-UP
TORQUE
1.
2
3.
4.
5
Place
the
empty
reel
and
attached
spring
scale
on
the
right
reel
table.
.
Place
the
unit
in
the
(mm)
play
mode.
Allow
the
rotation
of
the
reel
to
slowly
draw
the
scale
toward
the
hub.
Hold
the
spring
scale
with
enough
force
to
allow
a
steady
reading.
It
should
be
approximately
360%400g-cm(4.1%4.8
oz-inch).
§1OOV
AC
BACK
TENSION
TAKE-UP
REWIND
BACK
TENSION
FWN
Ee
Load
a
full
1,800ft
reel
of
tape
on
the
right
reel
table.
Place
the
empty
reel
with
2"
hub
on
the
left
reel
table.
Place
the
unit
in
the
fast
rewind
mode,
(=<).
At
this
time
observe
the
right
tension
arm.
Adjust
R-3
so
that
the
arm
moves
approx.
1"
to
the
right
and
remains
there.
130V
O12

BRAKE
TORQUE
NOTE
|
the
brake
torque
is
actuated
mechanically.
Pressure
is
set
by
the
variable
spring
force.
While
making
this
measurement
and
adjustment,
be
careful
not
to
bend
the
brake
bands.
As
brake
torque
will
change
with
cleaning,
brake
drums
and
brake
shoes
should
be
cleaned
only
when
absolutely
neces-
sary.
If
cleaning
is
required,
use
TEAC
cleaner
TZ-251B
only.
After
cleaning
operate
the
machine
for
some
time
before
performing
the
below
procedures.
;
Brake
adjustments
are
made
with
no
power
connected
to
the
equipment.
Procedure
for
Check
and
Adjustment
1.
2.
Place
an
empty
2"
hub
reel
on
the
left
reel
table,
and
fasten
one
end
of
a
30"
length
of
string
to
the
reel
anchor.
Wind
several
turns
of
string
counterclockwise
around
the
hub and
attach
a
suitable
spring
scale
to
the
free
end
of
the
string.
Slowly
draw
the
spring
scale
away
from
the
reel,
making
sure
that
the
string
does
not
rub
against
the
reel
flanges.
Take
a
reading
only
when
the
reel
is
in
steady
motion
since
the
force
required
to
overcome
static
friction
will
produce
a
false,
excessively
high
initial
reading.
The
reading
should
be
1.8
kg-cm
+0.1(25
oz-inch).
If
adjustment
is
required,
loosen
the
two
screws
shown
and
posi-
tion
the
brake
for
optimum
torque.
The
adjustment
of
the
right
brake
is
the
same,
with
the
exception
that
rotations
are
clockwise.
NOTE
The
difference
in
readings
between
the
right
and
left
brakes
should
be
kept
within
50
g-cm
(0.7
oz-inch).
ADJUSTMENT
SCREWS=>)_}
Fig.
6-4
Torque
Measurement
&
Adjustment
Location
~Brake-

REEL
HEIGHT
ADJUSTMENT
Reel
height
adjustment
is
required
only
if
a
motor
has
been
replaced.
Adjustment
is
accomplished
by
FINE
ADJ.
screw
in
the
reel
turntable.
Reel
turntable
height
should
be
adjusted
using
standard
7"
reels.
With
a
tape
threaded
on
the
machine,
position
the
reel
height
for
smooth
tape
travel.
FINE
ADJ.
SCREW
TAPE
SHOULD
WIND
EVENLY
ON
REEL
COARSE
ADJ-SET
SCREWS
Fig.
6-5
Reel
Height
Adjustment
FLUTTER
Flutter
should
be
measured
in
playback
mode
using
a
TEAC
flutter
free
tape
YTT-2003-2002
and
Meguro
model
MK665B
flutter
meter.
Measurement
of
flutter
should
be
made
in
accordance
with
NAB
standards.
Values
obtained
with
different
standards
or
equipment
cannot
be
compared.
Flutter
should
not
exceed.
7-1/2ips:
0.20%
3-3/4ips:
0.25%
These
figures
apply
to
any
tape
position
and
direction(such
as
full
take-up
reel,
full
supply
reel
or
about
mid
point).
TAPE
SPEED
The
tape
speed
should
be
measured
using
TEAC
flutter
free
tape,
model
YTT-2003-2002.
These
tapes
contain
a
highly
accurate
3
kHz
tone.
Connect
a
digital
frequency
counter
to
either
line
OUTPUT
jack.
The
indicated
frequency
should
be
3
kHz
0.7%
for
all
speeds.
FLUTTER
FREE
TAPE
FREQ.
COUNTER
METER
Fig.
6-6
Test
Equipment
Set-Up

VOLTAGE
AND
FREQUENCY
CONVERSION
Unit
must
be
set
to
the
power
line
frequency
available.
Improper
frequency
setting
will
result
in
a
20%
error
between
the
tape
speed
and
reel
motors
torque.
US
is
to
it
NOTE
model
is
preset
to
117V
AC
and
60
Hz.
No
frequency
conversion
required.
If
it
should
be
necessary
to
convert
the
A-2340
deck
operate
from
a
power
source
of
different
voltage
or
frequency,
may
be
easily
accomplished
as
follows:
Voltage
Conversion:
The
A-2340
may
be
set
for
100, 117,
200,
220
or
240
volts.
To
change
the
voltage
unscrew
the
fuse
in
the
center
of
the
voltage
selector
plug.
Pull
out
the
plug
and
reinsert
it
so
the
desired
voltage
shows
in
the
cut-out.
Reinstall
ca
the
fuse.
Fig.
6-7
Voltage
Conversion
Frequency
Conversion:
.
Remove
the
power
cord
and all
connecting
cables.
Take
off
tape
deck
rear
cover
by
removing
the
six
Screws
holding
it.
To
convert
the
unit
from
50
to
60
Hz
operation
reposition
the
capstan
belt
as
shown
in
the
illustration
below.
Slide
frequency
selector
switch
inside
the
rear
of
the
tape
deck
must
be
switched
to
the
frequency
of
the
power
line.
Reinstall
rear
cover.
CAPSTAN
FLYWHELL
0-0398
Fig.
6-8
Frequency
Conversion

7.MEASUREMENT
AND
ADJUSTMENT
—ELECTRICAL—
GENERAL
NOTICE
Outlined
procedures
refer
only
to
FRONT
channels,
the
same
procedures
also
apply
to
REAR
channels.
Before
performing
checks
set
all
head
function
selector
switches
to
NORMAL
posi-
tion
(on
the
head
housing).
Place
MONITOR
switches(L1-R3,
L2-R4)
in
TAPE
position,
place
tape
speed
control
at
H(high),
place
PLAY
switch
in
4
CHAN
position.
Power
supply
check
and
adjustment.
Check
the
voltage
at
VR-1
and
adjust
to
24V
DC
if
required.
(Refer
to
control
board
on
the
schematic
diagram.)
Procedures
for
checks
and
adjustments,
unless
otherwise
indicated,
are
for
the
left
channel
at
a
tape
speed
of
7-1/2ips.
The
same
proce-
dures
are
to
be
applied
to
the
right
channel
and
again
for
both
channels
at
3-3/4ips.
All
controls
mentioned
in
this
book
will
be
mae
AD!
printed
in
bold
letters
and
will
be
exactly
as
they
appear
on
the
unit.
Double
designated
symbol
numbers
refer
to
left
channel/right
channel.
Fig.
7-1
Adjustment
Locations
Only
FRONT
adjustments
are
illustrated,
REAR
adjustments
are
identical.
PLAYBACK
EQ.
(HIGH)
PLAYBACK
EQ.
(LOW)
PLAYBACK
LEVEL
VR202
VR204
PLAYBACK
METER
LEVEL
VR303
r
VR306
REC
METER
LEVEL
VR301
VR304
|
SOURCE
MONITOR
LEVEL
C301
L
303
REC
EQ.
VR302
VR305
RECORD
LEVEL
L
302
L
304
BIAS TRAP
vc501
|
vc503
BIAS
NORMAL
ADJ.
L
vc502
|
vce504
|
BIAS
HIGH
ADJ.

PLAYBACK
HEAT
ee
Sil
o
S700
PLAYBACK
PERFORMANCE
Fig.
7-2
Simplified
Diagram
~Playback-
PLAYBACK
HEAD
AZIMUTH
ADJUSTMENT
Coarse
Adjustment
Connect
a
level
meter
to
either
OUTPUT
jack.
Thread
a
TEAC
test
tape
YTT-1003
on
the
unit.
Play
the
15
kHz
test
tone
in
section
2
of
the
test
tape.
Slowly
rotate
the
azimuth
screw
until
maximum
indication
is
obtain
on
the
level
meter.
NOTE
If
during
playback,
a
slight
pressure
on
the
heads
results
in
a
rise
of
the
reading
of
the
level
meter,
head
alignment
ad-
justments
should
be
accomplished.
Fine
Adjustment
CAUTION
After
coarse
adjustment,
do
not
make
large
corrections,
turn
azimuth
screw
1/4
turn
or
less.
It
is
absolutely
essential
to
accomplish
the
coarse
adjustment
before
using
this
method
to
avoid
phase
errors
larger
than
45?
Connect
the
test
equipment
as
shown
in
Fig.
7-3.
-
Play
a
10
kHz
signal
and
adjust
the
azimuth
screw
until
the
oscilloscope
shows
that
the
signals
are
less
than
45°
in
phase.
Secure
the
screw
with
a
drop
of
LOCTITE.

SPECIFIED
1.
OUTPUT
LEVEL
SET
NOTE
Connect
a
10
k2
load
to
the
OUTPUT
jacks
when
not
using
TEAC
M-826A
(0
dB
=
0.775V)
output
meter.
Play
the
400
Hz
tone
in
section
1
of
the
test
tape.
This
tone
is
recorded
at
operating
reference
level
(1%
of
the
THD
level).
THD:
Third
Harmonic
Distortion
Turn
the
OUTPUT
controls
fully
clockwise,
and
adjust
VR-
201/203
for
+2
dB
reading
on
level
meter.
.
Then
retard
OUTPUT
controls
until
a
-8 dB
is
obtained
on
the
level
meter
at
the
OUTPUT
jacks.
.
Align
the
reference
marks
of
the
4
OUTPUT
controls
so
that
they
are
positioned
alike.
This
will
be
at
approximately
the
the
two
o'clock
position.
OUTPUT
2-O’CLOCK
POSITION
IMPORTANT
SPECIFIED
LEVEL
This
is
the
specified
output
.
level
set.
Do
not
disturb
this
setting
until
the
re-
maining
adjustments
have
been
completed.
VU
METER
CALIBRATION
1.
2.
While
playing
the
400
Hz
tone
(1%
THD)
in
section
1
of
the
test
tape.
With
MONITOR
switches
FRONT
and
REAR
in
the
TAPE
position,
ad-
just
VR-202/204
for
a
reading
of 0
VU
on
the
VU
meters.
D-O39!
SIGNAL
RECORDED
TAPE
Fig.
7-3
Fine
Adjustment
Set-up
-Head
Azimuth-
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