Teac A-7300RX - Page 21

hhh RECORD PERFORMANCE
10-14
BIAS
TRAP
ADJUSTMENT
—_
22
RECORD
MODE
SW...
LEFT
and
RIGHT
(Both
ON)
Select
RECORD
/
PAUSE
mode
MONITOR
SW
.....----
2-2
e
ee ee
eee
TAPE
BIAS
and
EQ
SW
...
6...
cc
ee
eee
1
.
Load
TEAC
YTT-8013
Test
Tape
on
the
unit.
_
Remove
all
input
signals.
.
Connect
a
VIVM
or
oscilloscope
across
the
Bias
Trap
T.P.
(on
REC
AMPL.
UNIT)
and
ground.
See
Fig.
10-10.
.
Adjust
L-503/504
(on
REC
AMPL.
UNIT)
for
mini-
mum
reading
on
scope
or
VIVM.
Use
Plastic
Alignment
Tool.
ON REC AMPL. UNIT 1-622
Fig. 10-10 Bias Trap Test Point
10-15
BIAS
LEAKAGE
CHECK
5.
Adjust
L-251/252
(on
PLAY
LINE
AMPL.
UNIT)
for
minimum
bias
leakage
reading
at
OUTPUT
jack,
with
VTVM
or
oscilloscope
now
connected
to
said
OUT-
PUT
SOURCE/TAPE
jacks.
.
Specified
Level
should
be
—53
dB
(1.73
mV)
or
less.
10-16 RECORD HEAD AZIMUTH ADJ.
Tape SPEED SW... LOW (7-1/2 ips)
—FINE ADJUSTMENT—
NOTE: The effect of turning the azimuth screw will not
immediately register on the VTVM.
A slight delay will be noticed. Therefore, the screw
must be rotated slightly with a pause to see the
effect.
7. Connect a VITVM to the OUTPUT jack and an AF oscil-
lator to the LINE IN jack. (Fig. 10-11). Set the oscillator
to 10 kHz at -18 dB (97 mV).
. Begin recording (Depress RECORD and _ play buttons).
9. While recording adjust the azimuth screw (on Record
Head) for maximum reading on the VTVM.
ioe)
NOTE: It is absolutely essential to accomplish the coarse
adjustment before performing the fine adj. to
avoid phase errors greater than 45°
Tape SPEED SW... .. HIGH (15 ips)
10. Sweep the signal from 40 Hz to 16 kHz and adjust the
azimuth so all signals are within 45°between channels.
11. Secure the screw with insulating locking paint.
T-621
Fig. 10-11 Test Connections for Recording Check