Teac A-3440 - Monitor Performance Check -2; Monitor Level Check; Headphone Output Level Check; Record Performance Adj.

10-MONITOR PERFORMANCE CHECK -2
10-1 MONITOR LEVEL CHECK
OUTPUT SELECT SW...... SOURCE
INPUT SW ............... LINE IN
1. Apply a 400 Hz —12 dB (195 mV) signal from the oscil-
lator to the LINE IN jack 1.
2. Check for —8 dB (308 mV) at the OUTPUT jack. Also
check for 0 VU on the VU METER.
10-2 HEADPHONE OUTPUT LEVEL CHECK
MONITOR CONTROL VOLUME ... Maximum
NOTE: At this point both the INPUT control and the
OUTPUT control are at their Specified Settings.
3. Connect a 4 ohm non-inductive resistor across the head-
phone (PHONES) jack and connect the VTVM across
the resistor.
4. Depress the Headphone Selector Button for channel 1.
5.
The
VTVM
should
indicate
—19
dB
+1
dB
(77.5
mV
—
97.5
mV).
6. Depress the buttons for channels 2, 3 and 4 so that all
4 are depressed.
7. The VTVM reading should increase to —6 dB +2 dB
(308 mV — 489 mV).
7
)
—_
D>
T-1366
Fig. 8-7 Test Connections for Headphone Output Check
11-RECORD PERFORMANCE ADJ.
NOTE:
For
all
record
performance
measurements
and
adjustments
the
FUNCTION
SELECT
SW
should
be
ON
for
all
channels.
11-1 BIAS TRAP ADJUSTMENT
1. Remove all Input Signals.
<.
Thread
a
blank
tape
on
the
deck
and
depress
RECORD
and
PAUSE
buttons.
3.
Connect
a
VTVM
or
oscilloscope
to
Test
Point
(T.P.)
and
ground.
See
Fig.
8-8.
4.
Using
a
plastic
trimmer
tool,
adjust
the
BIAS
TRAP
L103
for minimum reading on the scope or meter.
BIAS REC
TRAP EQ
REC/PLAY PCB
AC Voltmeter
Fig. 8-8 Bias Limits Chart
11-2 RECORD BIAS ADJ.
Tape
SPEED
Selector
SW.
.
.
LOW
(7-1/2
ips)
OUTPUT
SELECTSW.........
:
PLAY
NOTE:
Be
sure
the
Bias
Trap
has
been
adjusted
as
per
section
11-1.
5.
Apply
a
7
kHz
signal
at
-22
dB
(61.5
mV)
to
the
LINE
IN
jack.
6.
Turn
the
trimmer
capacitor
C381
fully
counter-clockwise.
7.
While
recording
on
the
YTT-8013
blank
tape,
slowly
turn
the
Trimmer
Capacitor
clockwise
until
the
reading
peaks
and
continue
turning
clockwise
until
the
reading
backs
off
2
dB.
8.
These
procedures
are
repeated
for
channels
2,
3
and
4,
NOTE: The Trimmer Capacitors are located on the BIAS
P.C.B. Refer to page 16 Adj. Location and Adj.
points.
—~> OUT
——> BIAS
T- 712
Fig. 8-9 Bias Limits Chart
19
oS a PN ROT ON RES Ce EAL A Oe OEE eer TR RTE SET ERED CORR Sen ES RE ee Sa ae Ve CRC