Table of Contents
Advertisement
12-17.
Overall Frequency
Response Measurement
Connection:
As shown in Fig. 12-25.
Switch Setting:
MONITOR
switch 0...
TAPE
VR Setting:
AUX
VOLUME............. indicated on
page 25
Procedures:
(1)
Be sure that the trap coil adjustment
has
been made.
(2)
Thread
a blank tape.
(3)
Deliver
a | kHz signal of -40 dB (7.75 mV)
into
the AUX
INput jack and
record
the
signal on the blank tape and memorize the
VTVM
reading.
(4)
Deliver
50Hz,
100Hz,
5kHz,
7kHz,
12.5kHz
and
18 kHz
signals
in turn and
record
them
on
the
blank
tape
and
memorize
the VTVM
readings respectively.
(5)
Be sure that each deviation in level against
1kHz
signal is within
the values shown in
the table below.
If not,
perform
the
record
equalizer and
the record bias adjustments.
noe
REC Amp.
tape, blank
LINE
OUT
Fig. 12-25
Overall frequency response
measurement setup
Deviation against the 1 kHz signal
19cem/s | 4.
a
Fe
:
Tips | 34B
+ 34B
9.5cm/s
|+ 3
(334 ips) |- 1098
"4.8cm/s +
3
(1% ips) |- 10
dB
12-18.
Overall S/N Ratio Measurement
Connection:
As shown
in Fig, 12-26.
Switch Setting:
MONITOR
switch......... TAPE
VR Setting:
AUX
VOLUME............. indicated on
page 25
Procedures:
(1) Thread a blank tape.
(2) Deliver
a
| kHz
signal
of -10dB (0.24V)
into
the
AUX
INput
jack
and
record
the
signal on the blank tape.
(3)
Remove
the input connection
of the audio
generator
and
terminate
the
MIC
and the
AUX
INput jacks with the dummy
resistors
(MIC—6002,
AUX-10k2).
(4)
Rewind
the recorded
tape and erase a part
of the recorded
tape
(record mode
with
no signal input).
(5) Be sure that the ratio of the recorded part
of the tape to the erased part on the VTVM
is more
than 45 dB.
tape, blank
AF
osc
REC Amp.
AU
1 kHz, -10 dB
LINE
OUT
Fig. 12-26
Overall S/N ratio measurement setup
12-19.
Distortion
Measurement
Connection:
As shown in Fig. 12-27.
Switch Setting:
MONITOR
switch ......... TAPE
VR Setting:
AUX
VOLUME............. indicated on page 25
Procedures:
(1) Before measuring the distortion, be sure that
the trap coil adjustment
has been
made.
— 36 —
Advertisement
Table of Contents
