 |
|||
|
|
|||
| ||||||||||
|
|  MIL-V-85033A(AS)
the rms acceleration level, The power spectral density of the test control
signal shall not deviate from. the specified requirements by more than +1OO,
-50 percent (3 dB) between 20 Hz and 2,000 Hz, except that deviations as
large as +300, -75 percent (6 dB) shall be allowed over a cumulative band-
width of 100 Hz, maximum, between 500 and 2,000 Hz.
Tolerance levels in terms of dB are defined as:
Where W1 = measured acceleration power spectral density of
2
g /HZ units.
The term W0 defines the specified level in g2/Hz units.
Confirmation of these tolerances shall be made by use of an anlysis system
providing statistical accuracies corresponding to a bandwidth-time constant
product. BT = 50 minimum. Specific analyzer characteristics shall be as
specified below or equivalent.
a.
On-line, contiguous filter, equalization/analysis system
having a bandwidth = B = 50 HZ maximum.
b.
Swept frequency analysis systems characterized as follows:
(1.)
Constant bandwidth analyzer.
(a) Filter bandwidth as follows:
B = 20 Hz, maximum between 20 and 200 Hz.
B = 50 Hz, maximum between 200 and 2,000 Hz.
(b) Analyzer averaging t i m e = T = 2 R C = 1 second,
minimum, where T = true averaging time and RC =
analyzer time constant.
(c) Analysis sweep rate [linear) = S =
see, whichever is smaller.
(2.) Constant percentage bandwidth analyzer.
(a) Filter bandwidth= pf = one third octave minimum
(0.23fc) where p = percentage and f c = analyzer
center frequency.
(b) Analyzer averaging time = T = 50/pfc, minimum.
16
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals