Measuring The Sound Level - Monacor SM-2 Manual De Instrucciones

5 Measuring the Sound Level

1) For a precise measurement, check the calibration
beforehand: Set the sliding switch (9) to the
position "CAL" . 94 .0 dB should be displayed . If
not, adjust the trimming control (5) by means
of a screw driver so that 94 .0 dB is displayed .
2) For measuring the sound level in accordance
with the auditory sensation of the human ear,
set the sliding switch to the position "A" . In the
position "C", the physical sound level is meas-
ured (linear) .
3) For measuring, hold the meter horizontally
with the microphone (1) pointing to the sound
source .
4) After switching on, the lower measuring range
35 – 100 dB is always selected . On the left side
of the display "Lo" is indicated .
When measuring values exceeding 100 dB,
"OVER" is indicated at the right bottom of the
display . In this case, switch to the upper range
65 – 130 dB with the key Lo / Hi (3) . Instead of
"Lo", "Hi" is displayed .
When measuring values below 65 dB in the
upper range, "OVER" is also indicated . In this
case, return to the lower range with the key Lo / Hi .
5) After switching on, the dynamic measuring
mode is set to sound levels changing fast . On the
right side of the display, "F" (fast) is indicated .
For measuring sound levels changing slowly,
switch to the second mode with the key S / F (4) .
The indication changes from "F" to "S" (slow) .
6) For holding the present value measured, press
the key HOLD (8) . At the top of the display
"DATA HOLD" is indicated . To return to the
present value measured, actuate the key HOLD
once again .
7) To determine the maximum level occurring, press
the key MAX (6) . At the top of the display "MAX
HOLD" is indicated . Now the level value of the
highest volume occurring after actuating the key
MAX will be held . For switching off the function,
actuate the key MAX once again .
Notes:
a The sound level measured largely depends on the
distance of the meter from the sound source . When
measuring, observe a defined distance (e . g . 1 m for
speaker measurements) or state the distance at which
the measurement was made .
b The level measured also depends on the angle to the
sound source . It may be necessary to measure the lev-
els at different angles (but at the same distance) to
determine the sound radiation be haviour of the sound
source .
5.1 Picking up a Microphone Signal or
a DC Voltage proportional to Level
At the output jack (7), the following voltages are
pres ent to be picked up for a control depending on
the level or for further analysis . For this purpose,
connect a 3-pole 3 .5 mm plug to the jack .
Signals at the 3 .5 mm plug connected
tip – body:
microphone signal
in the lower measuring range "Lo" 38 mV/dB
in the upper measuring range "Hi" 8 .3 mV/dB
impedance 100 Ω
ring – body:
DC voltage proportional to level 10 mV/dB
impedance 100 Ω
6 Specifications
Display: � � � � � � � � � � � � � � �17 mm LCD, 3½ digits
Measuring ranges
Lo (low):� � � � � � � � � � � � �35 – 100 dB
Hi (high): � � � � � � � � � � � �65 – 130 dB
Resolution: � � � � � � � � � � �0�1 dB
Accuracy: � � � � � � � � � � � � �±1�5 dB at 94 dB, 1 kHz
Frequency range: � � � � � � � �31�5 – 8000 Hz
Level weighting: � � � � � � � �A or C
Type of microphone: � � � � �electret microphone
Output jack (signals at the plug)
tip – body: � � � � � � � � � � �microphone signal,
ring – body: � � � � � � � � � �DC voltage proportional to
Ambient temperature: � � � �0 – 40 °C
Power supply: � � � � � � � � � �1 × 9 V battery
Dimensions, weight: � � � � �63 × 253 × 30 mm, 250 g
Subject to technical modification .
All rights reserved by MONACOR
GmbH & Co. KG. No part of this instruction manual
may be reproduced in any form or by any means for
any commercial use.
impedance 100 Ω
level 10 mV/dB, 100 Ω
INTERNATIONAL
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