VTVM
Fig.
10
Conditions for measurement :
Power voltage ...... DC 6V
Volume control ...... Maximum
Equipment required:
VTVM, AF OSC, oscilloscope, resistors (8Q, 10Q, 1000, 600Q).
SIGNAL SOURCE
OUTPUT
ITEM
CONNECTION
CONNECTION
MODE
ADJUSTMENT
SPEC.
REMARKS
Adjust the AF OSC to
obtain a circular and
Measurement of
Oscilloscope with
stationary Lissajous'
oscillation
aoe
AF OSC, as shown | Record
=
40+
pattern on the oscilol-
fsaien
in fie. 9
5 kHZ}
scope.
Bias oscillation
quency.
8. ¥ .
frequency is indicated
by the scale of the AF
OSC.
VTVM to both
Measurement of
ends of erase
Record
6V
7
erase current.
head, as shown in
fig. 10.
Set the volume control
to ee
Measurement of
100 resistor and
Bias curren
recording bias
—_
VTVM, as shown
Record
——
75+
O79
0.09 m8)
wy
0.5 mV
Voltage value
current.
in fig. 11.
(7.5-£0.5 mV)
™ Resistance
value
(109)
1 kHz —72+4 dB
Measurement of
to MIC input jack,
| The same as
Stop the bias oscillator
recording level.
as shown in
above.
Recors
Sc ad
by removing R17.
fig. 12.
Measurement of
1kHz ~80+3dB
| VTVM with 8Q
playback amplifier
| as shown in
resistor to EXT SP | Playback
ee
1V
——-
gain.
fig. 13.
jack.
:
Head angle
Head angle
Thread 3 kHz
ee
SP | Playback
adjustment
Maxi
adjustment.
alignment tape.
}
¥
screw @.
sata
jack.
:
See fig. 14.
Record Mode
