Introduction, Key features – General Tools and Instruments DSM403SD User Manual

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INTRODUCTION

Thank you for purchasing General Tools & Instruments’ DSM403SD Class 1 Sound Level
Meter with Excel-formatted Data Logging SD Card. Please read this user’s manual carefully
and thoroughly before using the instrument.

The DSM403SD is a general-purpose handheld instrument that measures the noise level of
an environment or the amplitude of sound produced by a piece of machinery. Using an
integrated 0.5 in. condenser microphone, the meter can measure sound levels from 30 to
130 dB with a resolution of 0.1 dB and show the results on a front-panel LCD.

Several features and capabilities enhance the meter’s versatility. Among them are the
option to make measurements using autoranging or any of three manual ranges, the ability
to hold readings and display maximum and minimum readings, and user-settable
measurement parameters such as frequency weighting (using the “A” and “C” standards)
and time weighting (fast or slow). The DSM403SD can be calibrated by an optional
laboratory instrument.

Because it is microprocessor-based, the DSM403SD can make full use of the portability,
reliability and large storage capacities that SD memory cards offer. Measurements can be
made automatically at any sampling rate between one second and one hour. After time-
stamping and storing the measurements on an SD card plugged into the instrument (a
process called data logging), the user can remove the card and plug it into to a laptop or
desktop computer either directly or via a USB card reader. The data logs are stored on the
card as files with the .xls extension, which can be opened by Microsoft’s Excel application.

The DSM403SD has a backlit 2-1/2 in. diagonal display and is powered by six “AA”
batteries or an optional 9V AC/DC adapter.

KEY FEATURES

• Big (2.5 in. diagonal) front-panel green backlit LCD is easy to read

• Makes measurements in autoranging mode or within any of three manual ranges

• Displays maximum and minimum readings and holds any reading

• Performs automatic data logging at sampling time settable from 1 second to 1 hour

• Also supports continuous manual data logging and changing of card storage location

• Outputs Excel-compatible data logs

• Accepts SD memory cards of up to 16 GB capacity

• Auto power off function that can be disabled to enable long-term data logging