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 1-7/8 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
obtain sufficient calibration voltage
1-7/8 IPS. Nominal frequency of tape
for the Flutter Meter.
at this speed will be 3KHz .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 1.5% RMS.
urements made during the operational
f. Set AGC-MAN switch to MAN
testing procedures.
position. Adjust GAIN control 1 to
maximum. Set SPEED control to 1-7/8
8-37. Variable Speed.
IPS. Set CHANNEL SELECTOR switch to
position 1. Repeat steps a. through
a. Adjust GAIN control 1 to maximum
e.
IPS
and set SPEED SELECTOR to
position.
b. Connect counter and oscilloscope to
8-39.
Frequency Response
HEADPHONE jack. Insert into the unit a
cassette test tape prerecord with a
a. Set speed at 15/16 IPS.
3 .5% of signal at 1 7/8 IPS."
c. Place unit into REPRODUCE mode of
b. Set oscillator to 1KHz, 0dB output.
operation.
Put unit in RECORD mode.
d. Turn VARY speed control to the
c. Set gain of each channel for an
extreme counterclockwise position.
output of +7dBm.
Note and record percentage of deviation
from basic frequency of tape. Speed
d. Reduce oscillator level to -10dB.
variation should be at least 30%.
Reset counter to 000.
e. Repeat step d. with the VARY speed
e. Record 5 to 10 counts at each of
control set to the extreme clockwise
these frequencies: 1KHz, 200Hz, 400Hz,
position.
2KHz, 4KHz. (When testing 1-7/8, also
8KHZ).
f. Adjust GAIN control 2 to maximum.
IPS
Set SPEED SELECTOR
f. Rewind to 000 on counter. Put
position.
unit in REPRO.
g. Repeat steps b. through e.
g. Set output of each channel to
Note: At 1-7/8 IPS, nominal frequency
0dB during 1KHz playback, using MAN
of tape is 3KHz.
GAIN CONTROL. This becomes the
h. Deleted.
relative zero dB point.
8-38. Wow and Flutter.
a. Connect Wow and Flutter Meter to
output of HEADPHONE jack.
8-24
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