Norsonic Nor1212, Instruction Manual

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Norsonic Nor1212
User Guide
5
2 Technical description
The Outdoor Kit, Nor1212, is designed to
operate in combination with Norsonic
microphone Nor1225 and the preamplifier
Nor1201 or Nor1206.
Some other types of free-field microphones
such as the Nor1223, Nor1226 and 1227 may
also be used with minor modifications of their
frequency and directional response as specified
for Nor1225.
Note that Nor1220 microphone should not to be
used with the Outdoor Kit as its uncompensated
frequency response may not be within the
requirements for a class 1 sound level meter.
If you need to connect the microphone system
to the measuring instrument with a coaxial
cable, we recommend to use the pre-polarised
microphone Nor1227 in combination with a
suitable ICP® type of preamplifier. We
recommend Nor1207 with desiccator TA202
(You need the desiccator due to the size of
Nor1207).
The outdoor kit Nor1212 protects the normal
measurement microphone Nor1225 from rain,
dust and insects, which sometimes may creep
behind the normal microphone grid. The
construction is shown on figure 2.1.
The microphone is mounted inside a tube. The
sound enters the microphone through 12
acoustic ports placed equidistantly around the
circumference. These ports have a drip-edge to
prevent water from entering the tube. For
Figure 2.1 The sound reaches the microphone through
the mesh and acoustic ports.