Sankyo STD-1700 - Playback Level and VU Meter Calibration; Playback Equalizer Adjustment; Recording Current Calibration; Bias Current Adjustment

14
6.7
6.8
6.9
6.10
Playback level and VU meters
Playback the test tape (MTT-150) and adjust R110 (left channel) and R210 (right channel until an output of
—2.5 dB is obtained from pins 3 and 5 of the DIN jack. Then adjust R127 (left channel) and R227 (right channel)
until the meter indicator diflects to +3 VU.
Playback equalizer
Set the EQ switch to CrO2, play the test tape (MTT-116K) and adjust R105 (left channel) and R205 (right channel)
until the frequency response from the LINE OUT terminals is of the same level at 500 Hz and 2 kHz. Then adjust
the parts marked with A in the mounting diagram C102, C103 (left channel), C202, C203 (right channel) until the
frequency response from the LINE OUT terminals is of the same level at 2 kHz and 10 kHz (see Note No. 3 of
the mounting diagram).
40 125 315 6.3K 10K
Recording current
Load the MTT-502 tape. Set the EQ and bias switches to NORM and apply an input of -20 dB, 400 Hz to the
LINE tN terminals. In the record mode adjust the RECORD LEVEL control until the meter indicator deflects to
+3 VU. Play the tape back and adjust R143 (left channel) and R243 (right channel) until the output is +3 VU (at
this time the semi-fixed resistor for bias current adjustment should be at the mechanical mid-position.)
600 Q 600 2 LINE IN
e =
Bias current
Load
the
MTT-502
tape.
Set
the
EQ
and
bias
switches
to
NORM
and
the
DOLBY
NR
switch
to
ON.
Apply
an
input
of
-20
dB
to
the
LINE
IN
terminals
and
adjust
the
RECORD
LEVEL
contro!
until
the
meter
indicator
deflects
to
+3
VU
at
1
kHz.
Then,
apply
an
input
of
-50
dB
(1
kHz
or
10
kHz)
to
the
LINE
IN
terminals
and
record.
Play
the
tape back and
adjust
R146
(left
channel)
and R246
(right
channel)
until
the
playback
outputs
of
the
LINE OUT
terminals
of
1
kHz
and
10
kHz
are
of
the
same
level
(at
this
time,
the
OUTPUT
LEVEL
control
is
at
maximum).
600 2 600 22 LINE IN LINE OUT
CY) ATT DECK VTVM
40 125 400 Normal (Fe203) 6.3K 10K