RV-B550BU
1-18
Standard values for confirmation of electronic performance
Items
Condition
Method for adjustment
and confirmation
Standard
value
Parts to be
adjusted
Erasing
current
(standard
and
reference
value)
Fast-forward and
rewind direction:
Recording mode
AC-514 for TYPE II,
AC-225 for TYPE I
Measuring terminal:
Both erase head ter
minals
Load the test tape (AC-514 for TYPE II,
AC-225 for TYPE I) into the tape
playback mechanism and preset it to the
record-pause mode.
After setting it to the recording mode,
send 1 M in series to the erase head and
measure the erasing current from both
erase head terminals.
TYPE II: 110
mA
TYPE I: 75 mA
Adjustment of
reproduction
of frequency
characteristics
Standard frequencies:
1 kHz and 10 kHz
(REF: -20 dB)
Test tape: TYPE II:
AC-514
Measuring input
terminal: OSC IN
Load the test tape (AC-514 for TYPE II,
AC-225 for TYPE I) into the tape
playback mechanism and preset it to the
record-pause mode.
Input the standard value of -20 dB and
the standard frequencies of 1 kHz and 10
kHz repeatedly to the microphone input
from the transmitter in the recording
mode. Adjust VR31 for Lch and VR32 for
Rch so that the difference in level
between 10 kHz and 1 kHz is -1 dB 5
dB.
Repeat the above for TYPE I and confirm
that the difference in level is -XdB dB.
Difference in
output
between 1 kHz
and 10 kHz: -1
dB 5 dB
Lch: VR31
Rch: VR32
Sensitivity of
reproduction
of
microphone
mixing
Microphone input
terminal: 1 kHz, -65 dB
Test tape: VT-724
Based on the reproduction level of the
VT-724 test tape, confirm that the
microphone level is 0 dBs 3 dB when a
1 kHz, 65 dBs signal is input.
(The mixing volume and sound volume
should be at maximum.)
0 dBs 3 dB
(Based on the
reproduction
level of the
VT-724)
(U version only)
