Norsonic nor118, Instruction Manual

Page: 101 / 116

88 Chapter 18
Technical specifications
89 Norsonic Nor118
User Guide
Setting the amount of attenuation:
• In the Correction menu, press 1 (Corr.par) to gain
access to the correction parameter setup menu. Press
2 to gain access to the attenuation setting itself. Never
change this setting unless you know what you’re doing!
Use the   to set the attenuation
value. Press  twice to leave the menu. See Fig.
on the previous page for menu details
Self-noise compensation
e displayed values for -, - and -weighted levels may,
as an option (extension 20), be corrected automatically for
the self-noise of the microphone. e noise levels for each
of the spectral weightings must be specified. e correc-
tion is applied by unlinear level subtraction. e option
allows levels close to the self-noise to be displayed with
reduced level linearity error. When the level is equal to
the self-noise level, the correction is –3 dB.
Diffraction around the instrument casing
e instrument casing is designed to have low effects on
the sound measured at the microphone. e figure below
shows the measured effect of the instrument casing at
reference environmental conditions.
General I/O socket
A 15 pin socket for general / is placed on the right-hand
side of the instrument. Socket type:  -
1
 --
1.
The general
I
/
O
socket