General Tools DSM8925 User Manual
DIGITAL SOUND
METER WITH
JUMBO DISPLAY
USER’S MANUAL
DSM8925
Please read this manual carefully and thoroughly
before using this product.
TABLE OF CONTENTS
Introduction . . . . . . . . . . . . . . . . . . . . . . 3
Key Features . . . . . . . . . . . . . . . . . . . . . 4
What’s in the Box . . . . . . . . . . . . . . . . . 5
Product Overview . . . . . . . . . . . . . . 5 – 7
Setup Instructions . . . . . . . . . . . . . . . . . 8
Install Batteries . . . . . . . . . . . . . . . . 8
Operating Instructions . . . . . . . . . 8 – 15
Making Basic Measurements . . 8 – 9
Autoranging vs.
Manual Ranging . . . . . . . . . . . 9 – 11
Time and Frequency
Weighting Options . . . . . . . . . 11 – 12
Storing and Recalling
MIN and MAX Readings . . . . 12 – 13
Operating in
MAX HOLD mode . . . . . . . . . . 13 – 14
Disabling Auto Power Off . . . . . . . 14
Calibrating the Meter . . . . . . . . . . 15
Specifications . . . . . . . . . . . . . . . . . . . 16
Maintenance Tips . . . . . . . . . . . . . . . . 17
Warranty Information . . . . . . . . . .17 – 18
Return for Repair Policy . . . . . . . . . . . 18
2
INTRODUCTION
Thank you for purchasing General Tools &
Instruments’ DSM8925 Digital Sound Meter
with Jumbo Display. Please read this user’s
manual carefully and thoroughly before using
the instrument.
The DSM8925 uses an integrated condenser
microphone to measure the noise level of an
environment or the loudness of a machine,
typically in order to comply with health and/or
safety rules. The meter has a range of 30 to
130 dB and an accuracy of ±2 dB. Real-time
measurements are shown within a backlit
liquid-crystal display window in two forms: as
a three- or four-digit number, and as a line on
an analog bar graph.
Several features improve the meter’s
versatility. Among them are two userselectable operating modes: “A” or “C”
frequency weighting, and fast or slow time
response. Users also can override autoranging
(the default mode) and manually select a fixed
measurement range, improving the meter’s
response time and measurement resolution.
The meter can display the minimum and
maximum sound levels measured during a
recording session, as well as hold a maximum
level on-screen until it is exceeded.
3
Physical features of the DSM8925 include an
analog output jack for connecting to a data
logger or chart recorder, a tripod mounting
socket, and an adjustment screw for
calibrating the meter to a standard 94 dB
input.
The DSM8925 includes a wind shield ball
and is powered by four “AAA” batteries
(also included).
KEY FEATURES
• Measures sound level of a machine
or an environment
• Jumbo LCD is easy to read
• “A” or “C” frequency weighting
• Fast or slow time weighting
• Autoranging or manual ranging
• Displays maximum and minimum readings
• Max reading can be held until exceeded
• Auto power off
• Analog output for data logging
• Calibrates to standard 94dB signal
• Tripod mount socket on back
• Includes wind shield ball
• Powered by four “AAA” batteries
4
WHAT’S IN THE BOX
The DSM8925 comes fully assembled in a box
along with a wind shield ball, four “AAA”
batteries and this user’s manual.
PRODUCT OVERVIEW
Figure 1 shows all of the controls, indicators
and connectors on the front and right side of
the DSM8925. Familiarize yourself with their
positions and functions before moving on to
the setup procedure.
1. The DSM8925’s controls, indicators
and connectors
A. Wind shield ball
B. Microphone
C. Liquid-crystal display
D. Power on/off button
E. A/C—Selects “A” or “C” frequency
weighting
5
B
C
D
E
F
G
H
I
J
K
A
FRONT
RIGHT SIDE
F. R E C —Enters/exits Recording mode
G. RNG—Selects autoranging or manual
ranging
H. F/S—Selects fast or slow time response
I. MAX HOLD button
J. Calibration adjustment screw
K. Analog output jack
Figure 2 shows all text and icons that could
appear in the display window at various times.
2. All possible display indications and their
meanings
REC Meter is in Recording mode, tracking
maximum and minimum sound level
measurements
MAX Digital readout is highest level
recorded since entering Recording
mode
MIN Digital readout is lowest level
recorded since entering Recording
mode
MAX HOLD Meter is in Max Hold mode. Digital
readout is highest level measured
since entering this mode
6
Loading...