Model 90 Quantifier Sound Level Meter
Page 16
preamplifier from the Sound Level Meter.
Using Microphone Extension Cables
The MODEL 90 instruments can be used with a microphone extension cable if the
instrument is fitted with the removable preamplifier. If a microphone extension cable is
to be used during a measurement, the instrument must be calibrated with the cable
attached.
Connect the microphone extension cable in the same manner as the MV:200C
Preamplifier.
Batteries
The batteries of the MODEL 90 are located behind the cover on the bottom of the
instrument. Slide the cover to the right hand side to remove and to access the battery
holder.
Ensure the instrument is switched off. Remove the battery holder from the instrument
and insert the batteries. The MODEL 90 instruments uses two AA type batteries, also
known as LR6.
Ensure that the batteries are inserted correctly. DO NOT reverse the polarity
of the batteries as this may cause damage to the instrument.
