Convergence Instruments NSRTW mk3 User manual

NSRTW_mk3
User’s Manual
January 29 2019
Bruno Paillard

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1INTRODUCTION _____________________________________________ 3
2APPLICATIONS ______________________________________________ 3
3WARNINGS _________________________________________________ 4
4GETTING STARTED __________________________________________ 4
4.1 Software Installation ____________________________________________________________ 4
4.2 Hardware Installation___________________________________________________________ 4
4.3 Initial Test and Configuration ____________________________________________________ 5
5INSTRUMENT FUNCTIONS AND DESCRIPTION ___________________ 5
6PRINCIPLE OF OPERATION____________________________________ 6
6.1 Power Consumption ____________________________________________________________ 6
6.2 Battery Charging_______________________________________________________________ 6
6.3 Modes of Operation_____________________________________________________________ 7
6.4 LED Indicators ________________________________________________________________ 7
6.4.1 Charge LED________________________________________________________________ 7
6.4.2 Operation LED _____________________________________________________________ 8
6.5 Sound Level Calculation_________________________________________________________ 8
6.6 Manual Recording______________________________________________________________ 9
6.7 Automatic Recording with WiFi™ Connection (“W” model only) ______________________ 10
6.7.1 WiFi™ Connectivity ________________________________________________________ 10
7INSTRUMENT_MANAGER APPLICATION________________________ 12
7.1 Starting the Application ________________________________________________________ 15
7.2 Main Functions _______________________________________________________________ 16
7.3 Setup Tab ____________________________________________________________________ 16
7.3.1 Time and Date Field ________________________________________________________ 16
7.3.2 Temperature Field __________________________________________________________ 16
7.3.3 Instrument Info Field________________________________________________________ 16
7.3.4 Recording Field ____________________________________________________________ 17
7.3.5 Settings Field______________________________________________________________ 18
7.3.6 Battery Field ______________________________________________________________ 21

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7.3.7 Signals Field ______________________________________________________________ 21
7.4 Records Tab__________________________________________________________________ 21
7.4.1 Instrument Download _______________________________________________________ 21
7.4.2 File Save _________________________________________________________________ 22
7.4.3 File Open _________________________________________________________________ 22
7.4.4 Exporting Data_____________________________________________________________ 22
7.4.5 Global Level Calculations ____________________________________________________ 22
7.4.6 Graph Controls ____________________________________________________________ 23
7.4.7 Cursor Control_____________________________________________________________ 23
7.5 Spectrum Tab_________________________________________________________________ 24
7.5.1 Window __________________________________________________________________ 24
7.5.2 Weighting ________________________________________________________________ 24
7.5.3 Scale ____________________________________________________________________ 24
7.5.4 Cursor, Zoom and Pan_______________________________________________________ 25
7.6 WiFi Tab (“W” model only) _____________________________________________________ 25
7.6.1 Connection Status __________________________________________________________ 25
7.6.2 Cloud Setup _______________________________________________________________ 26
7.6.3 WiFi Settings (Without Cloud Service)__________________________________________ 29
7.6.4 Manual Connection _________________________________________________________ 30
7.6.5 Setting Up the Server to Work in a Local or Wide Area Network. _____________________ 30
7.6.6 Email Setup (Without Cloud Service) ___________________________________________ 31
7.6.7 WiFi™Battery Drain _______________________________________________________ 33
8INSTRUMENT_LISTENER APPLICATION ________________________ 33
8.1 File Storage___________________________________________________________________ 34
9MAINTENANCE _____________________________________________ 35
9.1 Battery Care__________________________________________________________________ 35
9.2 Reset Procedure_______________________________________________________________ 35
9.3 Operation Outdoors ___________________________________________________________ 35
9.4 Cleaning _____________________________________________________________________ 35
9.5 Software and Firmware Upgrades________________________________________________ 35
10 TROUBLESHOOTING_______________________________________ 36
10.1 USB Power Limitation _________________________________________________________ 36
10.2 USB Driver Installation_________________________________________________________ 36
10.3 Connection Problems __________________________________________________________ 36

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1Introduction
NSRTW_mk3 is the third generation of Convergence Instrument’s WiFi™ enabled smart integrating
sound-level meter/datalogger. It includes a type 1 digital MEMS microphone, an accurate date/time
clock, a non-volatile 128 Mb recording memory and wireless connectivity with fast USB and WiFi™
download (“W” model only).
Running on battery, it can record sound pressure levels and report them through WiFi™for a week.
Connected to an external USB charger it can record and report for months. Its very small size allows it
to be attached to or embedded within the monitored equipment.
The NSRTW_mk3 includes the following features:
•Type I precision.
•A, C and Z weighting curves.
•Integrating Sound-Level Meter, records L-max, L-min and Leq levels.
•Log interval adjustable from 125 ms (8 points per second) up to hours.
•Individual Manufacturer’s Certificate of Calibration from Convergence Instrument provided with
every instrument purchased.
•WiFi™connectivity to report measured levels remotely and automatically at preset intervals
(“W”model only).
•Email alarms for sound detected over specified threshold, as well as low-battery.
•Digital very sensitive MEMS microphone (30 dBA typical noise floor).
•Completely sealed weatherproof enclosure designed for outdoors applications.
•All-digital design.
•Ultra-stable sensitivity (field recalibration is easily done, but seldom required).
•Very low sensitivity variation due to temperature changes.
•Very low sensitivity to vibrations.
•Software function calculates global Leq and/or dose, according to ISO and OSHA methods.
•Adjustable response time.
•Preprogrammed recording start date/time.
•Integrated oscilloscope function that can show the acoustic signal in real time.
•Integrated spectral analyzer function that can show the spectrum (or 3rd-octave bands) in real
time.
•Can be used as a high-quality USB digital microphone.
•Allows the observation of recorded levels while the recording is ongoing.
•Works standalone, or USB connected.
•Long life internal rechargeable battery that recharges from USB and most USB chargers.
•Can be field-calibrated.
•Observes and records 100% of the acoustic signal (no missed samples).
•Editable individual custom ID for easier instrument management.
•All settings are stored in non-volatile memory. So the instrument will regain full functionality
and WiFi™connection from hard-reset or battery loss.
•Compatible with Convergence Instrument’s Cloud service.
2Applications
•Sound level and acoustic dose measurement and recording.
•Monitoring of safe working conditions.
•24/7 monitoring of construction noise.
•Email Alarms when the noise is too loud.
•Activity detection and logging.
•Long-term measurement and recording of acoustic levels for environmental impact studies.

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•Specially designed for long-term outdoors applications.
3Warnings
Never blow air at the microphone.
Avoid over-discharging the battery
•Recharge the instrument immediately if the LED indicates a low-battery condition.
•Even if the instrument is Idle all or most of the time, recharge it fully at least once every 6
months.
•When leaving the instrument idle for a long time, make sure the WiFi™periodic connection is
disabled.
Do not store or operate the instrument at temperatures exceeding the following limits
•-20 °C to 60 °C (-4 °F to 140 °F)
When using the instrument outdoors, make sure the USB connector is facing down.
This way rain will not accumulate in the connector and microphone port.
4Getting Started
4.1 Software Installation
•On the PC that is used to setup the instrument, run Instrument_Manager_Installer.exe. This
installs the Instrument_Manager application, as well as its USB driver and documentation.
•On the PC that is used as a server, to collect data over the network (“”W”model only), run
Instrument_Listener_Installer.exe. This installs the listener application that is used to respond
to instrument’s incoming connections, and create and fill the corresponding data files.
Note: The same PC can be used for both applications.
Note: Perform the software installation above BEFORE connecting the instrument to the PC for the
first time.
4.2 Hardware Installation
1. Connect the instrument to an available USB port on the PC

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2. Verify that the PC properly detects the instrument and loads the driver. In case of doubt see
section Troubleshooting.
4.3 Initial Test and Configuration
1. Upon connection to the PC, the charge LED should light-up yellow (charging) or green
(charged). The operating LED should blink once per second.
2. Go into Start\All Programs\Convergence_Instruments\Instrument_Managerand run
Instrument_Manager.exe. The front-panel described in Figure 2 appears, and the application
tries to connect to the instrument. If it fails to find the instrument it indicates No Device Found. If
this is the case see section Troubleshooting
3. Otherwise the application switches-on the NSRTW_mk3 and starts communicating with it.
4. If the Time and Date in the upper right corner of the application window are not properly
adjusted the application asks if you want the instrument time to be synchronized to the PC
time. Only say YES if the PC time is correct.
5. In addition, the application detects if the time zone of the instrument is different from the time
zone of the PC. If it is, the application asks to set the instrument to the same time zone as the
PC.
Note: If (in rare cases) the instrument is not intended to be used in the same time zone as
that of the PC used to configure it, we suggest to temporarily change the PC’s time zone to the
time zone where the instrument will be recording, let the application set the instrument to the
PC’s time zone, and change the PC’s time zone back after that initial setting. Afterwards
if/whenever the application asks to change the instrument time zone back to the PC’s time
zone, simply choose to cancel the adjustment.
6. In the front-panel of the application you should see the acoustic signal display in real-time.
5Instrument Functions and Description
The instrument connects to a PC on a USB port. The Instrument_Manager application is used to set its
operating parameters and download recorded data.

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Figure 1 NSRTW_mk3
1. Charge LED
2. Operation LED
3. USB Connector
4. Reset Button
6Principle of Operation
6.1 Power Consumption
The NSRTW_mk3 is always on. However, when not in operation it only measures time, which only
takes a tiny operating current. In that Idle state it can stay on for up to 6 months.When the
NSRTW_mk3 is actively measuring, its power consumption allows it to record for 1 week.
The NSRTW_mk3 can be configured to connect to a server at regular intervals. When that function is
enabled, the NSRTW_mk3 will activate its WiFi™ interface at the defined interval, and attempt to
connect via WiFi™ for up to 1 minute. During that time, the instrument’s power consumption will be
increased. If the connection fails the NSRTW_mk3 will fall back to its previous state (Sleep or
Recording).
Note: WiFi™communications consume battery, so when leaving the NSRTW_mk3 unused for a
long time, it is important to disable the WiFi™periodic connection feature.
In applications where the NSRTW_mk3 must record for longer periods of time, it can be connected to a
USB charger https://convergenceinstruments.com/product/universal-usb-wall-charger-usbw-001\. For
outdoor-use, a USB-output solar panel, such as the one found in
https://convergenceinstruments.com/product/data-logger-accessories-solar-pannel/ is an ideal solution
that will power the instrument indefinitely.
6.2 Battery Charging
The battery charges whenever the following conditions are met:
•The battery has not reached full charge.
•The instrument is connected to a PC’s USB port and the PC is not in standby, or
•The instrument is connected to a USB charger.

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While charging, the charge LED is orange. When fully charged, the LED changes to green and the
charging stops.
The charge time from a completely discharged state varies with the amount of power the PC allows the
instrument to draw. Charge time is normally around 2H30. If the PC only allows 300 mA, the charge
time can increase up to 5 to 6 hours.
Note: When connected to a PC, battery charging stops while the PC is in standby.
Note: It is OK to leave the instrument connected to a PC or USB charger all the time. The smart
charger inside the instrument will stop charging as soon as the battery reaches full-charge.
6.3 Modes of Operation
The NSRTW_mk3 has four modes of operation:
Mode
Operation
Power Consumption
Idle
Disconnected from USB and not actively
recording - Only keeps time.
Minimal: can stay on for up to 6
months.
Active
Connected to USB – Not recording –
Instrument is fully on and measuring
Instrument draws power from USB to
power itself, and if necessary recharge
its battery. Battery is not depleted.
Recording
USB-connected or not - Fully on and
recording.
If USB-connected, power comes from
USB. If not, power comes from the
internal battery.
If not connected the
instrument can record for up to 7 days.
Periodic
WiFi™
Connect (“W”
model only)
From any state, including Idle and
Recording, the instrument can periodically
wake up its WiFi™interface and attempt
to connect to a server. If the connection is
not established after 1 minute it falls back
to its original state until the next connection
time.
If USB-connected, power comes from
USB. If not, power comes from the
battery. The Periodic Connect feature
consumes battery. This is especially
the case if the connection interval is set
to be short so it occurs often.
Table 1
6.4 LED Indicators
The NSRTW_mk3 has two LED indicators:
6.4.1 Charge LED
The charge LED is always fully on or off.

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LED State
Meaning
Off
Instrument is disconnected, or is connected to a PC that is in standby.
Green
Instrument is connected to a PC or USB charger, and the battery is full.
Orange
Instrument is connected to a PC or USB charger, and the battery is charging.
Table 2
6.4.2 Operation LED
The operation LED is always blinking.
LED State
Meaning
Off
Instrument is in Idle mode.
1-blink/second
Instrument is in Active mode, but is not actively recording.
2-blinks/second
Instrument is actively recording.
1-blink/second
(off-beat)
Instrument is presently communicating with a server via WiFi™
4-blinks/second
Battery is low. Recharge as soon as possible. If the battery level becomes critical
the instrument will go to Idle mode (LED-off) in order to safeguard the battery
against over-discharge as much as possible.
Table 3
6.5 Sound Level Calculation
After extracting the signal power, the calculated sound levels are low-pass filtered (smoothed) using an
adjustable time constant. This time constant is applied to the calculation of L-min and L-max, but not
Leq. A typical short time constant (125 ms) allows the measurements to track sharp changes, while a
longer time constant (1s) provides more stable (cleaner) RMS values that averages-out short
transients.
The Leq is integrated linearly over the specified log interval, irrespective of the time constant setting.
The sound level statistics (L-min, L-max and Leq) are gathered for the specified log-interval before
being written to the recording memory. The log-interval represents the interval at which the selected
statistics are written to memory. Therefore a longer log-interval uses less memory, while a shorter log-
interval provides better time resolution and allows the user to distinguish between events that occurred
close together. The statistics (L-min, L-max and Leq) are reset at the beginning of each log-interval.
Then the statistics are gathered sample-by-sample during the log-interval. At the end of each log
interval the calculated statistics are written to memory, and the next log-interval is started. No portion of
the signal is overlooked.
The log interval is set to 1 second by default. It can be set to as short as 1/8 s.

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Note: The time constant only affects the calculation of Lmin and Lmax. The Leq is integrated linearly
over the specified log interval.
6.6 Manual Recording
Every time a recording is started, a new record is created in memory and filled until the recording is
stopped. That record is time-stamped, so the signals can be displayed with respect to absolute
date/time. Records are stored sequentially in the instrument’s memory. There is no limit to the number
of records that the memory can contain, only a limit to the total size of the data recorded. The
Instrument_Manager application displays the total memory recording time as a function of the various
setup parameters.
After (or while) recording, the records contained in memory can be downloaded from the instrument
and observed or exported. In case a recording is ongoing the last record is only displayed up to the
present time.
The recording is stopped automatically when the recording memory is full. This way a new record will
not overwrite an old one.
The recording memory is non-volatile, so there is no risk of losing the data that has already been
recorded, even in the case of a reset or battery failure.
Note: It is perfectly legal to find empty records in memory. That occurs typically when a recording is
started and stopped quickly (for a time shorter than the log interval), before any data had time to be
written to memory. In that case only the time-stamp is written to memory.
An empty record can also occur when a recording was started but no data (Lmin, Lmax or Leq) was
selected to be recorded.
To record sound levels proceed as follows:
1. Select the statistics to be recorded (L-min, L-max and/or Leq).
2. Select the log-interval. Note that the total recording time is automatically calculated and
displayed by the Instrument_Manager application, as a function of the log-interval and statistics
selected. The log-interval is adjustable in 125 ms increments, from 125 ms up to 2H.
3. Select the time constant used to smooth the measured sound levels for L-min and L-max.
Choose the Fast time constant (125 ms) to be able to detect short peaks and valleys. Choose
the Long time constant (1 s) to provide cleaner more stable sound levels. Or adjust to another
value, as required by the application.
4. When ready to start a recording immediately, simply press the Record button. Press Record
again to stop the recording.
5. Or to set a start time/date:
•Check to make sure that the instrument time is correct. If that is not the case press the
Sync button in order to automatically set the instrument time to the PC time.
•Press the Timer button. Set a start time and date using the calendar.
•Click OK to arm the trigger.

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6.7 Automatic Recording with WiFi™ Connection ( “W” model only)
The NSRTW_mk3 supports a mode of operation where it periodically connects to a server (a Windows
PC running the Instrument_Listener application) through WiFi™, or Convergence Instrument’s cloud
solution. This feature is designed to let the instrument record autonomously, periodically report the
levels recorded since the last connection, and optionally send emails with noise-level or low-battery
alerts. When set, this feature will work, even if the instrument is reset, or if it loses and regains battery
power (for instance if the instrument is reconnected to a charger after the battery has been completely
drained).
This PC-server being connected-to does not have to be in the vicinity of the instrument. It can be a
continent apart, as long as it is reachable through the internet, and all firewalls have been set to allow
the connection.
The instrument connects to a WiFi™ Router or Access Point that is in its vicinity. From there, it will find
the server to connect to, either by its IP address, or by its domain name.
6.7.1
WiFi™ Connectivity
6.7.1.1 WiFi™ Reporting Without Cloud Service
Note: When using the instrument with WiFi™ connectivity, do not start a recording manually, or via
the timer. The instrument will be completely controlled by the server, including starting the recording,
erasing memory if required, and resetting the time.
When using the WiFi™feature, the instrument will try to connect to a known server at regular intervals,
or immediately in case of alarm.
Whenever it connects, the instrument will talk to a special Instrument_Listener application running on
the server. That application will do the following:
•If the instrument was recording:
oUpload the latest recorded data from the instrument and updates a growing file with
that data (create the file if it was not already created).
•If the instrument was not recording (for instance if the recording was stopped earlier because
the memory was full):
oUpload the latest recorded data from the instrument (if any) and update the recording
file.
oAdjust the instrument time (does not adjust the time zone of the instrument, just
precisely readjust the Universal-Time-Code running in the instrument).
oDelete all data in the instrument’s memory (all that data has already been safely
stored in the recording file on the server).
oStart a new recording.
6.7.1.2 Email Alarms
In addition to trying to connect to the server at regular intervals, the instrument will try to connect
immediately to the email server in case of alarm. The alarm function does not require the use of a
server or Listener application. The instrument will typically connect to an email server, such as a gmail
account.

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In order to be able to send an alarm email, the instrument must have the following setup:
•A WiFi™ Router or Access Point must be in the instrument’s vicinity, and the instrument must
have been configured with that router’s connection parameters. That is part of the WiFi Setup
of the instrument.
•The instrument must have been configured with an outgoing email account and connection
parameters. That is part of the Email Setup of the instrument.
Two alarms can be enabled:
•A noise level over a preset threshold.
•The battery is close to being depleted.
6.7.1.3 WiFi™ Reporting Via Cloud Service
Reporting and email alerts via the cloud service work exactly like reporting without the cloud service,
except that it uses Convergence Instrument’s servers, and the user does not have to deploy their own
server for the instruments to be able to connect. In addition the user can view and download their
instrument’s data from anywhere in the world, using any platform that has a web browser, including
PCs, phones, tablets… etc.
More information about the cloud service can be found at:
https://convergenceinstruments.com/data-collection/

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7Instrument_Manager Application
Figure 2 Setup Tab
1. Real-Time Acoustic signal
2. Auto-Range button
3. Memory fill indicator
4. Timer button
5. Record button
6. Instrument Time indicator
7. Tab selector
8. Instrument Temperature indicator
9. Erase button
10. Instrument User ID
11. Instrument Information
12. Settings button
13. Field calibration button
14. Battery Condition, Charge and Recording Time Field
15. Sound Level indicator

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Figure 3 Record Tab
1. Cursor field
2. Recorded levels
3. dB/Lin button
4. Pan and zoom buttons
5. Record number selector
6. Cursor
7. Data source
8. File Save button
9. File Open button
10. Instrument Download button
11. Export button
12. Global level/dose calculation method
13. Global Level/Time-Weighted-Average value
14. Percentiles

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Figure 4 Spectrum Tab
1. Cursor, Zoom and Pan controls
2. Cursor values display
3. dB/Lin button
4. Auto-scale button
5. Cursor
6. Spectrum
7. Spectral controls
8. Spectrum reset button

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Figure 5 WiFi Tab
1. Connection Test Button
2. Disable All WiFi Button
3. Cloud Setup Button
4. Email Setup Button
5. WiFi Setup Button
6. Name (SSID) of WiFi Access Point or Router
7. IP address of the instrument
8. WiFi Active Indicator
9. Link Indicator
10. Router or Access Point Connected Indicator
11. Network Connected Indicator
12. Server IP address
13. Server Connection Indicator
14. Email Active Indicator
7.1 Starting the Application
Note: The application can be run with or without an NSRTW_mk3 connected. When an
NSRTW_mk3 is not connected the application can only be used to display and analyze a previously
saved log file. All the controls and indicators related to the instrument are grayed out.
To control an NSRTW_mk3 using the Instrument_Manager, proceed as follows:

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1. Connect the instrument to an available USB connector on the PC.
2. Make sure that the charge LED lights-up yellow or green, and that the operation LED starts
blinking. If not, review the installation procedure, or see section Troubleshooting.
3. Go to Start\All-Programs\Convergence_Instruments\Instrument_Manager, and run
Instrument_Manager.exe.
4. The front-panel described in Figure 2 appears, and the application tries to connect to the
instrument. If it fails to find the instrument it indicates No Device Found. If this is the case see
section Troubleshooting.
5. Otherwise the application immediately starts communicating with the NSRTW_mk3.
7.2 Main Functions
The application has four main tabs:
•The Setup Tab: Is used to setup the instrument and monitor real-time signal (see
Figure 2).
•The Records Tab: Is used to download, display and export the data from the
NSRTW_mk3 (see Figure 3).
•The Spectrum Tab: Is used to display a real-time power spectrum from the NSRTW_mk3
(see Figure 4).
•The WiFi Tab: Is used to display the present connection state of the NSRTW_mk3,
and to setup its connection parameters (SSID, Security, Password…etc.) (see Figure 5).
7.3 Setup Tab
The setup tab is seen in Figure 2. It is divided into seven fields.
7.3.1 Time and Date Field
This field displays the internal time of the instrument. If the instrument time is not properly adjusted,
press Synchronize. This synchronizes precisely the instrument time to the PC time. Make sure the PC
time is accurate before synchronizing the instrument.
Note: Time synchronization is not allowed while the instrument is recording.
7.3.2 Temperature Field
This field is used to display the instrument’s internal temperature in °C or °F. It is normal for the internal
temperature to rise slightly while the instrument is charging.
7.3.3 Instrument Info Field
The instrument info field provides instrument information, such as instrument model, serial number and
firmware revision. In addition the User-ID field may be used to assign a custom identifier to the
instrument.

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To set, modify or delete the User-ID, simply place the cursor in the User-ID box and write a new
identifier or clear the text. The new identifier is written to the instrument’s memory as soon as return or
enter is pressed, or if the mouse is left-clicked outside of the box.
The User-ID is written to non-volatile memory, so it is retained even in the event of a reset or battery
failure.
7.3.4 Recording Field
Note: When using the instrument with WiFi™ connectivity, do not use any of the controls in the
Recording field. The instrument will be completely controlled by the server, including starting the
recording, erasing memory if required, and resetting the time.
The recording field has three buttons:
•Record The Record button is used to immediately create a new record and start
recording. The new record is placed in memory immediately after the last one. The recording
stops when the memory is full, or when the Record button is pressed again. The recording
parameters, such as number and types of values recorded…etc. must be adjusted prior to
starting the recording.
•Timer The Timer button is used to set a time and date to start the recording
automatically. This is only allowed when a recording is not already in progress. To set the
timer, press the Timer button. Then set the recording date and time, and press the OK button
to arm the timer.
•Erase The Erase button erases unconditionally all the data that has been recorded
in the instrument, making room for new records.
The Memory Depth bar provides two indications:
•The percentage of memory already used (indicated by the green bar). The bar is completely
grey when the memory is empty and completely green when the memory is full.
•The total memory time, in Days-Hours-Minutes-Seconds. The total memory time is displayed
at the right extremity of the scale. It is calculated as a function of the instrument settings, such
as log interval, statistics recorded…etc. Therefore it will change dynamically as the settings
are modified, to reflect the new overall memorytime.
7.3.4.1 Timer Setting
When the Timer button is pressed, the timer settings panel appears.
Either use the direct entry field (Figure 6 (4)), or press the Calendar View button (Figure 6 (3)) to set
the date and time when the recording must start.
Press the OK button to exit and arm the timer.
Press the Cancel button, or the Window-Close button to exit without arming the timer.

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Figure 6 Timer Settings Panel
1. Cancel button – Closes the window without arming the timer
2. OK button – Closes the window and arms the timer
3. Calendar button – Brings the calendar view to enter date and time
4. Date/Time field – Can be used to enter date and time directly
5. Window close button - Closes the window without arming the timer
Figure 7 Calendar View
1. Cancel button – Closes the window without changing the date/time setting
2. OK button – Closes the window and accepts the newly set date/time
3. Set to Now button – Set the time and date to the present time
4. Date setting field – Click a date to set
5. Time setting field – Use the field to set a new time
6. Window close button - Closes the window without changing the date/time setting
7.3.5 Settings Field
The settings field contains the Settings and Calibration buttons.
7.3.5.1 Instrument Settings Panel
The instrument settings panel opens when the user presses the Settings button. Changing the settings
is only allowed when the instrument is not actively recording.

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Figure 8 Instrument Settings Panel
1. OK button – Closes the window
2. Recall Button – Recalls a configuration from a configuration file
3. Save Button - Saves a configuration to a configuration file
4. Time constant for sound level measurement (only affects Lmin and Lmax)
5. Recorded Data selector
6. Log interval control
7. Bandwidth Selector
8. dB-A/dB-C/dB-Z selector
7.3.5.1.1 dB-A/dB-C/dB-Z Selector
Use this selector to choose the weighting curve. The default is dB-A, which approximates the sensitivity
of human hearing.
7.3.5.1.2 Bandwidth Selector
Use this selector to choose the sampling frequency/bandwidth.
•16 kHz bandwidth (32 kHz sampling frequency)
•24 kHz bandwidth (48 kHz sampling frequency)
7.3.5.1.3 Log Interval
The log interval defines the time between two successive recorded points. That also defines the
integration period for the LEQ, and the observation period for L-min and L-max.
The log interval can be adjusted from 125 ms (1/8th s) to 2 H in increments of 125 ms.
The amount of memory consumed is inversely proportional to the log interval. The Memory-Depth
indicator in the Setup panel automatically calculates the overall recording time as a function of the
selection.