TM 32-5835-005-14 & P
b. Insert into the unit a cassette test
This speed is the nominal speed of the
tape prerecorded with a 3kHz .5% signal
tape transport. Note and record read
at 15/16 IPS. Turn GAIN CONTROL 1 fully
readings. Speed should not be off more
clockwise. Set CHANNEL SELECTOR switch
than 5% around the indicated speed.
to position 1.
c. Place unit into REPRODUCE mode of
f. Repeat steps a. through e. at
operation, adjust GAIN of recorder to
1-7/8 IPS. Set SPEED SELECTOR to 1-7/8
obtain sufficient calibration voltage
IPS. Nominal frequency of tape at this
for the Flutter Meter.
speed will be 6KHz .5%
d. Calibrate Flutter Meter and take
NOTE
10 readings across the length of the
tape.
The measured nominal speeds of the tape
e. Average readings of Meter. Note and
transport will serve as the reference
recordreadings. Readings should not
speeds with respect to all speed meas-
exceed 6.3% peak-to-peak.
urements made during the operational
f. Repeat steps a. through e. at
testing procedures.
1-7/8 IPS using a 3KHz .5% signal at
15/16 IPS cassette in unit.
8-37. Variable Speed.
a. Adjust GAIN control 1 to maximum
Frequency Response
8-39.
15/16 IPS
and set SPEED SELECTOR to
position.
a. Set speed at 15/16 IPS.
b. Connect counter and oscilloscope to
HEADPHONE jack. Insert into the unit a
cassette test tape prerecorded with a
b. Set oscillator to 1KHz, 0dB output.
3kHz .5% signal at 15/16 IPS."
Put unit in RECORD mode.
c. Place unit into REPRODUCE mode of
c. Set gain of each channel so that
operation.
Vu Meter is in middle of red scale.
(This sets record gain).
d. Turn VARY speed control to the
extreme counterclockswise position.
d. Reduce oscillator level to -10dB.
Note and record percentage of deviation
Reset counter to 000.
from basic frequency of tape. Speed
variation should be at least 30%.
e. Record 5 to 10 counts at each of
these frequencies: 1KHz, 200Hz, 400Hz,
e. Repeat step d. with the VARY speed
2KHz, 4KHz. (When testing 1-7/8, also
control set to the extreme clockwise
8KHZ).
position.
f. Rewind to 000 on counter. Put
f. Adjust GAIN control 2 to maximum.
unit in REPRO.
Set SPEED SELECTOR to
1-7/8 IPS
position.
g. Set output of each channel to -10dB
during 1KHz playback, using MAN GAIN
g. Repeat steps b. through e.
CONTROL. This becomes the relative zero
Note: At 1-7/8 IPS, nominal frequency
dB point.
of tape is 6KHz.
h. Deleted.
8-38. Wow and Flutter.
a. Connect Wow and Flutter Meter to
output of HEADPHONE jack.
8-24
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