Technics RS-646DS-D User Manual

ADJUSTMENTS
Before
measuring
and
adjusting
“Overall
frequency
response”,
“Overall
distortion”
and
“Overall
S/N
ratio”.
confirm
that
the
characteris-
tics
of
5
items
below
are
within
standard
which
have
much
relation
to
or
influence
on
electrical
performances
above.
1. Head azimuth adjustment. 2. Bias current. 3. Playback gain. 4, Overall gain.
5. Playback frequency response.
I. TEST INSTRUMENTS
1. Prepare test instruments which are equivalent in accuracy to those shown below.
2.
The
test
instruments
should
be
inspected
and
corrected
by
specialists
once
every
6
months,
because
a
long
period
of
use
without
maintenance
may
increase errors in
indication.
3.
Warm-up
the
test
instruments
for
30
minutes
and
the
set
to
be
measured
for
10
minutes
before
taking
the
measurements.
_
If
not,
there
may
arise
an
error
or
difference
between
the
initial
value
and
the
stabilized
value
measured
after
“aging”
4. Specifications of test instruments.
(1) Audio frequency oscillator
a. Oscillation frequency: 5Hz~ 500 kHz (5 ranges)
b. Frequency tolerance: +(3% +1Hz)
c. Sine wave
* Output voltage (at 25°C): 5Vrms £10% (without load)
2.5Vrms +10% (with 6002 load)
* Output frequency response: Within £0.2 dB, 20Hz~20kHz
Within £0.5dB, 5Hz~ 500 kHz
* Distortion factor: Not more than 0.05%, 200 Hz ~ 20kHz
Not more than 0.5%, 5Hz~ 500 kHz
* Output impedance: 6002 unbalanced, within + 15%
* Output attenuator: OdB, 20dB, error; within +0.2dB
d. Temperature in use of set: Temperature = 0 ~ 40°C, humidity = 90% or less
(2) Automatic-stop distortion meter (with vacuum tube voltmeter)
A. Distortion factor measurement
a. Frequency (fundamental wave): = 400Hz, 1kHz +10%
b. Measurement: 0.1~ 100% (6 ranges)
c. Input: 50mV~50V
d. Fundamental wave attenuation: 60 dB or more
B. Level measurement
a. Measurement: mV (—60 dB) ~ 30 V (30 dB) (9 ranges)
b. Frequency response (1kHz basis): 20Hz~100kHz £0.3¢dB
c. Input impedance: 1MQ2 +10%, less than 50 pF
d. Error in indicated value: Within £3% at 1kHz
C. Output terminal
a. Frequency response: OQHz~100kHz +1dB
100kH2~1MHz +3dB
b. Output voltage: 1Vrms + 10% (1kHz sine wave)

Technics RS-646DS-D Specifications

General

Brand	Technics
Model	RS-646DS-D
Category	Cassette Player
Language	English