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CRS-2104
6. ELECTRICAL ADJUSTMENTS
5.7, POSITIONING THE MOTOR PULLEY
AND MEASUREMENTS
Check to ensure that a clearance between the DC motor
and pulley is 3.1 mm.
!f out of specification, reposition
Precaution for Adjustment and Measurement
the pulley as shown.
1. Whenever adjusting or measuring any circuit, wipe the
heads clean with a soft cloth moistened with alcohol
or carbon tetrachloride. Also be sure to demagnetize
the heads, capstan, and similar parts.
2. The voltage at any electrical point may vary with the
input signal, so make measurements
of voltage under
no signal condition.
3. Transistors
are affected
by microvoltage.
Whenever
measuring on them, use
aVTVM having a high internal
resistance and high input sensitivity enough to elimi-
nate errors in measurement.
4. In adjustment or measurement, set the TONE control
to its mechanical center (''0') unless otherwise spec-
ified.
5. For measurements of outputs, connect a pure 4 22 re-
sistor across the external speaker terminal and use a
VTVM.
Unless
otherwise
specified,
adjust
the
VOLUME
control
for the standard
output
level, 50
mW (0.45 V/4 QQ).
5.8
ADJUSTING THE TAPE SPEED
Play the 3 kHz test tape back, and check to make sure
that the meter
pointer of a measuring instrument (fre-
quency counter) indicates 3000 Hz +2.5% or less as spec-
ified.
If it is out of the range, adjust the semifixed re-
sistor inside the motor.
After adjustment,
be sure to
stick seal on the hole for the resistor.
6.1
ADJUSTING THE PLAYBACK LEVEL
Play the 333 Hz level adjusting tape MTT 112 back and
inspect the R and L channel output voltages at the EXT
SP 4 Q jack. Adjust R804 until the output voltage of the
R channel coincides with that of the L channel. The out-
put voltage at EXT SP 4 2. jack will be around 0.45 V.
P E
py) are
PLAYBACK LEVEL."
C803 0.02/50V
R806 50k
(D)
R803 2.7 k
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