Technics RS-B555

RS-B555
OVERALL
FREQUENCY
RESPONSE
Normal!
Overall
frequency
response
chart
(NR
OUT)
1.
Insert
the normal
blank
test tape
(QZZCRA) and
set
the
unit
to
the
record
pause
mode.
7608
2.
Apply
a
reference
input
signal
(1kHz,
—24dB)
through
an
+408
attenuator. eee
3. Attenuate the signal by 20dB and adjust the frequency 0B
from 50H2~10kHz. ee
4. Record the frequency sweep. =a08
5. Playback the recorded signal and assure that it is within = baB 1
the range shown in Fig. 8 in comparison to the reference 50Hz 100Hz 200Hz 500Hz 1kHz 2kHz
frequency (1kHz).
6. If it is not within the standard range, adjust VR301 Fig. 8
(L-CH) and VR302 (R-CH) so that the frequency level is
within the standard range. CrO, Metal Overall frequency response chart (NR OUT)
¢
Level
up
in
high
frequency
range
Increase
the
bias
current.
¢ Level
down
in
high
frequency
range
...Decrease
the
bias
current.
+64B
7. Repeat steps 2~6 above using the CrO, tape (QZZCRX)
and the metal tape (QZZCRZ) increasing the frequency
range to 12.5kHz (50Hz~12.5kHz).
8. Assure that the level is within the range shown in Fig. 9.
+14
LINE IN LINE OUT
|
4
T
{
50Hz 100Hz 200Hz 500Hz 1kHz 2kHz ——+*12.5kHz
Fig. 9
EVM Oscilloscope
OVERALL GAIN ADJUSTMENT
. Insert the normal blank test tape (QZZCRA) and set the
unit to the record pause mode.
. Apply a reference input signal (1kHz, —24dB).
Attenuate the output so that its level becomes 0.4V.
. Record this input signal. LINE IN LINE QUT
. Playback the signal recorded in step 3 above, and assure
that the output is within the standard value.
. If it is not within the standard value, adjust VR3 (L-CH)
and VR4 (R-CH).
. Repeat the step 2~5 above until the output is within the
standard value.
Standard value: 0.4V+0.5dB
AF oscillator = ATT EVM Oscilloscooe