The recording of the synthetic random spectrum on the cassette is
procedurally identical to that used in the recording of the sine transfer tape
described in Chapter
3, Obtaining Sine Transfer Characteristics. The recording is made on the
same tape cassette as the sine sweep in accordance with the sequential steps
outlined in subsequent paragraphs.
4-5.2.1 Verify that the tape cassette is the correct one
for the test article and test setup. Determine which side of the cassette
corresponds to the test axis or condition to be recorded. Load the cassette
into the tape deck with the side designation required (A or B) facing
4-5.2.2 Rewind the tape cassette to its start position and
then set the tape deck counter to 000.
the tape deck counter reading for the end of the sine sweep. This information
is on the Tape Data Sheet, Figure 3-3
4-5.2.4 Advance the tape using the fast-forward control till the tape deck
counter reads 2 to 3 counts above that locating the end of the sine
4-5.2.5 Advance the tape using the play-back control (without recording)
for one minute of elapsed time. Stop the recorder at the conclusion of one
4-5.2.6 Switch the tape deck VU Meter for the left channel to record
(input) if manual switching is required.
4-5.2.7 Adjust the tape deck recording level control for the left channel
so that the left channel VU Meter reads between 0 and - 1.0 dB. The master
gain control of the random equalization system may also have to be
4-5.2.8 Place the tape deck in the record mode and record the random
voltage signal for an elapsed time of 17.5 minutes.
4-5.2.9 At the conclusion of 17.5 minutes gradually reduce the record level
control on the left channel to minimum. (For an elapsed time of approximately
4-5.2.10 Allow the tape deck to run with minimum input signal until it
automatically stops at the end of the tape.
all significant parameters (including tape recorder reading) on the Tape Data
Sheet. Figure 3-3