4: No A-Weighting; 75: Autospectrum Limit Db; 76: Weighted Tim~ U; 77: Weighted Time L - BRUEL & KJAER 2032 Instruction Manual

12.6.16. 74: No A-weighting
If Special Parameter 7 4 is set to 1, then the A-weighting selected by the A-weighting
field of the DISPLAY SETUP is disabled. Instead, a weighting function specified exter-
nally over the IEC/IEEE interface bus is selected.
12.6.17. 75: Autospectrum Limit dB
In a cepstrum calculation, Special Parameter 75 defines the lower limiting amplitude in
dB for the autospectrum on which the cepstrum is to be performed. The dB scale is
referred, in this case, to the maximum peak voltage setting for the channel in use.
12.6.18. 76: Weighted Time U
Special Parameter 76 allows the display of a time function for the upper trace to be
varied. The Parameter can be set to 0, 1, or 2.
0: gives normal display of the
time function
1: the time weighting function
is displayed instead of the
time function
2: the time function multiplied
by the time weighting function
is displayed instead of the
normal time function
12.6.19. 77: Weighted Time L
As for Special Parameter 76, but operating on the lower trace, see Section 12.6.9.
12.6.20. 78: Littered Cepstrum U
Special Parameter 78 allows the display of a Cepstrum for the upper trace to be
varied. The Parameter can be set to 0, 1 or 2.
0: gives normal display of the
Cepstrum
1: the lifter is displayed in-
stead of the Cepstrum
2: the littered cepstrum, that
is the original Cepstrum mul-
tiplied by the lifter is dis-
played instead of the Cep-
strum
12.6.21. 79: Littered Cepstrum L
As for Special Parameter 78, but operating on the lower trace, see Section 12.6.11.
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