The basic premise upon which the taped random vibration technique has been structured is that a low amplitude sinusoidal frequency sweep can be used in determining the equalization required to shape a specific random spectrum for a test system.
In order to use the random equalization so derived in test operations, two conditions should
a. The dynamic characteristics of the vibration
system must not vary significantly.
b. The random noise spectrum must be reproduced accurately without
This requirement for system stability is of primary importance for making
the technique practical in day to day test operations with many samples of a
The degree of success in achieving these conditions will determine the type
of limitations and test tolerances that must be applied to the technique.
This section will examine these requirements and the methods developed to
assure their achievement.