DIGITAL SOUND LEVEL METER USER’S MANUAL DSM8930 Please read this manual carefully and thoroughly before using this product.
TABLE OF CONTENTS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 – 3 Key Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 What’s in the Blister Pack . . . . . . . . . . . . . . . . . . . . . . 4 Product Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 4 – 5 Setup Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Install Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Operating Instructions . . . . . . .
and a digital display resolution of 0.1dB. Real-time measurements are shown on a green backlit LCD in two forms: as a three- or four-digit dB value, and as a moving vertical line on a horizontal analog bar graph. Several features improve the meter’s versatility. Among them are “A” frequency weighting and “fast” (125 ms) time response. The meter can display real-time readings or the minimum or maximum sound levels measured since being powered on.
WHAT’S IN THE BLISTER PACK The DSM8930 comes fully assembled in a blister pack along with a wind shield ball, one “9V” battery and this user’s manual. PRODUCT OVERVIEW Figure 1 shows all of the controls, indicators and connectors on the front, bottom and right side of the DSM8930. Figure 2 shows all text and icons that could appear on the LCD. Familiarize yourself with the positions and functions of these symbols and structures before moving on to the Setup Instructions. A Fig. 1.
Fig. 2. All possible display indications and their meanings MAX Digital readout is highest level recorded since meter was powered on MIN Digital readout is lowest level recorded since meter was powered on SPL Abbreviation of sound pressure level (the parameter measured) Meter’s battery is very low on charge and should be replaced dB Sound level unit (accompanies reading at its left) 40 Range Baseline (low end of current measurement range, in dB).
SETUP INSTRUCTIONS INSTALL BATTERY 1. The meter’s battery compartment (Fig. 1, Callout D) is accessible from the back of the unit near the bottom. Use a Phillips-head screwdriver to loosen the screw holding the yellow battery compartment cover in place. Set the cover and screw aside. 2. Remove the “9V” battery from the blister pack and plug it into the wired socket inside the compartment.
the meter is operating in Autoranging mode. To demonstrate that autoranging is on in a quiet environment, rub the windscreen with your hand (to simulate a loud noise) and watch the Range Baseline change to 100 dB. To measure the loudness of a sound source, point the microphone at it. The measurement calculation reflects the meter’s fixed settings: “A” frequency weighting and fast time weighting.
To display the maximum sound level measured since the meter was powered on, press the MAX button. The text MAX will replace MIN on the top line of the display and the digital display will indicate the highest sound volume measured since power on. While the digital display is showing the maximum sound value, the meter continues to measure realtime sound level inputs and to display its results on the analog bar graph.
SPECIFICATIONS Measurement Range 40 to 130 dB over four ranges (40 to 70 dB, 60 to 90 dB, 80 to 110 dB, 100 to 130 dB) Measurement Accuracy ±2 dB Display Size/Type 4-digit (4000 count) LCD Digital Display Resolution 0.1 dB Digital Display Refresh Period 160 milliseconds Analog Bar Graph Resolution 1 dB Analog Bar Graph 40 milliseconds Refresh Period Frequency Range 100 Hz to 8.3 kHz Time Weighting Time Constant 125 milliseconds Microphone Diameter/Type 0.5 in. (12.
MAINTENANCE TIPS When the icon appears at the upper right of the display, it’s time to replace the “9V” battery that powers the instrument (although measurements will remain valid for several hours after the icon first appears). To replace the battery, follow the instructions on p. 6. Remove the battery when storing the meter and when you do not expect to use it for an extended period of time (months rather than weeks). Do not drop or disassemble the meter or immerse it in water.
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GENERAL TOOLS & INSTRUMENTS 80 White Street New York, NY 10013-3567 PHONE (212) 431-6100 FAX (212) 431-6499 TOLL FREE (800) 697-8665 e-mail: sales@generaltools.com www.generaltools.com DSM8930 User’s Manual Specifications subject to change without notice ©2012 GENERAL TOOLS & INSTRUMENTS NOTICE - WE ARE NOT RESPONSIBLE FOR TYPOGRAPHICAL ERRORS.
