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Fast (F) and Slow (S) Response
Slide the Fast or Slow switch to select the response. Selection of Fast or Slow is determined by the
application and any directives or standards related to that application. For example, most hearing
conservation or OSHA related testing is done using SLOW and A weighting.
Setting the Range
Start with the highest range setting (120 dB) and work downward in range using the Rotary Switch until
there is significant deflection of the meter's pointing needle. For greatest accuracy, always use the lower of
any two possible settings. For example: If the RANGE is set to 80 dB and meter reads approx. -5, reset the
RANGE to 70 dB and the meter will read +3, for actual sound level of 73 dB.
Max Hold
Maximum Hold permits the user to freeze the meter's maximum reading by locking the needle indicator at
the sound level peak. Press the Max. button to activate Max. Hold. Press again to release.
Low Battery Indication
Place the Rotary Select switch to the 'BAT' position and observe the analog pointer for status of the battery
voltage. Replace the battery when the pointer indicates a weak battery. Remove power to the meter
whenever it is not being used to preserve battery life.