HTA102 Sound Level Meter User Manual

1. Precautions and Safety Measures

This instrument is designed in compliance with safety directives for electronic measuring instruments. For your safety and to prevent damage, carefully follow the procedures in this manual and pay close attention to notes preceded by the [Caution] symbol (⚠️). Observe the following instructions before and after measurements:

• Do not measure in humid environments.
• Do not measure in the presence of gas, explosive materials, flammables, or in dusty environments.
• Do not measure if you find anomalies such as deformation, substance leaks, or absence of display.

Symbols used in this manual:

• [Caution]: Observe instructions; improper use may damage the instrument or its components.
• [Double Insulation]: This instrument belongs to Class 2 (double insulation).
• CE: This instrument complies with CE marking standards.

1.1. Preliminary Instructions

• Follow standard safety rules to prevent incorrect use.
• If the instrument has not been used for a long time or was used in critical conditions, recalibration is recommended (see § 5.4).
• Ensure the battery is correctly inserted.

1.2. During Use

Please read the following recommendations and instructions carefully:

[CAUTION] Failure to comply with caution notes and/or instructions may damage the instrument or its components, or endanger the operator.

• Do not perform tests under environmental conditions exceeding limits indicated in § 8.3.
• Always use the wind protection screen for measurements in windy environments.
• Avoid mechanical shocks and keep the microphone dry.
• If the measured value remains unchanged during measurement, check if the HOLD function is enabled.

1.3. After Use

• Switch off the instrument after measurements.
• If the instrument will not be used for a long time, remove the battery.

2. General Description

The instrument offers the following functions:

• Measurement of Sound Pressure Level (SPL).
• Weighted frequency measurements using A or C curves.
• Measurements with FAST or SLOW integration.
• Measurement of maximum and minimum SPL values.
• Analogue AC/DC output for connection to external multimeters and dataloggers.
• Automatic range selection.
• PC connection via SoundLink software for recording operations.

Function keys on the front panel allow selection of these functions (see § 4.3). The measured value is displayed on the LCD with the unit and enabled functions. The instrument's side features the analogue AC/DC output, the terminal for external power supply (when not using the battery), the mini USB port for PC connection, and an adjustment trimmer. A hole on the back allows mounting on a tripod.

3. Preparation for Use

3.1. Initial Checks

The instrument was checked electrically and mechanically before shipping. While precautions were taken to ensure undamaged delivery, it is recommended to check for any transport damage. Contact the Dealer or HT's After-sales Service if anomalies are found. Verify that all components listed in § 8.4.1 are present. Contact the Dealer for discrepancies. For returns, follow instructions in § 9.

3.2. Instrument Power Supply

The instrument is powered by a 1x9V alkaline battery (IEC 6F22), included. The [Low Battery] symbol (?) appears when the battery is low. Replace the battery as per § 7.2. An external DC 9V supply (see § 8.2) can also be used.

3.3. Storage

For precise measurements after long storage or under extreme environmental conditions, allow the instrument to return to normal operating conditions (see § 8.3).

4. Nomenclature

4.1. Description of the Instrument

Figure 1: Description of the instrument

• 1. Wind protection screen
• 2. LCD display
• 3. Key [unspecified symbol]
• 4. Key MAX/MIN
• 5. Key REC
• 6. Key HLD
• 7. Key A/C
• 8. Key SET
• 9. Key F/S
• 10. Key LEV
• 11. Key ON/OFF
• 12. Microphone
• 13. Input for external power supply
• 14. Mini USB port
• 15. Analogue AC/DC output
• 16. Adjustment trimmer
• 17. Hole for tripod insertion
• 18. Battery compartment

4.2. Description of the Display

Figure 2: Display description

• 1. Low value indication (UNDER)
• 2. Active MIN function
• 3. Active FAST function
• 4. Full scale indication (OVER)
• 5. Active SLOW function
• 6. Measuring range indication
• 7. Active autorange
• 8. Active HOLD function
• 9. Weighting unit A (dBA)
• 10. Weighting unit C (dBC)
• 11. Active recording
• 12. Memory full
• 13. Low battery indication (?)
• 14. Active Auto Power OFF function ([APO])
• 15. LCD display
• 16. System time
• 17. Analogue bargraph
• 18. Active MAX function

4.3. Description of Function Keys

4.3.1. Key ON/OFF

Press ON/OFF to turn on the instrument. Press and hold ON/OFF until the countdown "3", "2", "1" finishes and "P-OFF" is displayed to turn off the instrument.

4.3.2. Key HLD

Press HLD to activate/deactivate the HOLD function, freezing the measured value on the display. The "HOLD" symbol appears. HLD is also used to confirm parameters during system date/time and sampling interval settings (see § 4.3.9).

4.3.3. Key [Backlight]

Press this key to activate/deactivate the display backlight. It can also be used to set the sampling interval during recording (see § 5.2).

4.3.4. Key A/C

Press A/C to select weighting curves A or C. Curve "A" is for general SPL measurements. Curve "C" is for SPL measurements with low-frequency components. If "C" results are much higher than "A", significant low-frequency noise is present. "dBA" or "dBC" is shown on the display.

4.3.5. Key LEV

Press LEV to select the measuring range (see Fig. 2, part 6). Available ranges: 30-80dB (low), 50-100dB (medium), 80-130dB (high), 30-130dB (Autorange). "AUTO" appears for Autorange. "UNDER" (Fig. 2, part 1) indicates a value below the selected range's minimum. "OVER" (Fig. 2, part 4) indicates a value above the selected range's maximum. LEV is also used for system date/time settings (see § 4.3.9).

4.3.6. Key F/S

Press F/S to select integration type: "FAST" for short SPL measurements (every 125ms) or "SLOW" for average SPL over time (every second).

4.3.7. Key MAX MIN

Press MAX MIN to activate/deactivate Maximum and Minimum SPL measurement. Select the appropriate range first (see § 4.3.5). "MAX" or "MIN" symbols appear on the display, showing the respective values, which update automatically. Press and hold MAX MIN (>2s) to exit and return to measuring mode.

4.3.8. Key REC

Press REC to activate/deactivate sound pressure level (SPL) recording (see § 5.2).

4.3.9. Key SET

Key SET allows:

• Activation/deactivation of the Auto Power OFF (APO) function. The [APO] symbol (⚙️) appears/disappears (not possible with HOLD active).
• Setting system date/time:
  1. Switch off the instrument (ON/OFF key).
  2. Press and hold SET, then switch on with ON/OFF. Release SET when "TIME" is shown. The current date (e.g., 26/03/18) is displayed (see Fig. 3).
  3. Press SET to enter "Minutes" programming.
  4. Press LEV to set Minutes, then SET to set Hour (see Fig. 3).
  5. Press LEV to set Hour (h-P for PM, h-A for AM).
  6. Press SET to set the Date (see Fig. 4).
  7. Press LEV to set Day, then SET to proceed (see Fig. 4 middle).
  8. Press LEV to set Month, then SET to proceed (see Fig. 4 right).
  9. Press LEV to set Year, then HLD to confirm date/time and exit.
  10. After setting the Year, pressing SET again shows the reset screen (see Fig. 5).

Figure 3: System time setting shows screens for date, minutes, and hour settings.

Figure 4: System date setting shows screens for day, month, and year settings.

Figure 5: Activating the instrument's reset

• Press SET to save date/time and exit.
• Alternatively, press HLD to reset system date/time to default configuration. This is useful if date/time cannot be set due to low battery or replacement.

5. Operating Instructions

5.1. Real-Time Measurement of Sound Pressure Level

[CAUTION] Always use the wind protection screen in windy conditions or if wind speed exceeds 10m/s. Avoid mechanical shocks and keep the microphone dry.

1. Switch on the instrument using the ON/OFF key.
2. Check and reset system date/time if necessary (see § 4.3.9).
3. Perform a full calibration if the instrument hasn't been used for a long time, using the mobile calibrator SC05 (see § 5.4).
4. Press A/C to select the weighting curve (see § 4.3.4).
5. Press F/S to select the integration type (see § 4.3.6).
6. Press LEV to select the appropriate range for SPL measurement (see § 4.3.5).
7. Read the measured SPL on the display.
8. For better comfort, use the provided tripod inserted into the threaded hole on the back (see Fig. 1, part 17).
9. Refer to § 4.3.2 and § 4.3.7 for HOLD and MAX MIN functions.

5.2. Recording of Sound Pressure Level

The instrument records SPL over time with a programmable sampling interval. Recordings are saved internally and can be downloaded via the SoundLink software.

1. Switch on the instrument (ON/OFF key).
2. Check and reset system date/time if necessary (see § 4.3.9).
3. Switch off the instrument (ON/OFF key).
4. Zero the internal memory: press and hold REC while switching on with ON/OFF. The "CLR" screen appears briefly (see Fig. 6).
5. Switch off the instrument (ON/OFF key).
6. Set the sampling interval: press and hold the [Backlight] key (as described in 4.3.3) while switching on with ON/OFF. The "Int" screen appears (see Fig. 7).
7. Press LEV to set the sampling interval (1s to 59s).
8. Press HLD to confirm and return to the measuring screen.
9. Perform a full calibration if the instrument hasn't been used for a long time, using the mobile calibrator SC05 (see § 5.4).
10. Press A/C to select the weighting curve (see § 4.3.4).
11. Press F/S to select the integration type (see § 4.3.6).
12. Press LEV to select the appropriate SPL measuring range (see § 4.3.5).
13. Connect the external power supply (see Fig. 1, part 13).
14. Press REC at the desired instant to activate recording. The "REC" message appears on the display (see Fig. 8).
15. Press REC again to end recording and save it.
16. Connect the instrument to the PC using the USB cable (see Fig. 1, part 14).
17. Launch the SoundLink software.
18. Press SET to disable Auto Power OFF (if not already done) and check the instrument-software connection (refer to software Help).
19. Select the "DataLogger" command in SoundLink. The PC displays a screen showing recorded data (see Fig. 9).

Figure 6: Zeroing of the internal memory shows a "CLR" display.

Figure 7: Setting of the sampling interval shows an "Int" display.

Figure 8: Activation of SPL recording shows the display with "REC", time, and measured value.

Figure 9: Download and display of recording on software SoundLink shows the software interface with a graph and data list.

Double-click the recording name to view the graph. For SoundLink usage, refer to the software's Help section.

Switch off the instrument using the ON/OFF key.

5.3. Connection to Analogue AC/DC Output

The instrument can connect to external multimeters or dataloggers for recording via the analogue AC/DC output (see Fig. 1, part 15) using a 3.5mm jack (not provided). The analogue output characteristics are:

• AC output: 1Vrms with respect to selected FS, Output impedance: 100Ω.
• DC output: Output: 10mV/dB, Output impedance: 1kΩ.

Figure 10: Analogue AC/CD output characteristics illustrates these specifications.

5.4. Calibration of the Instrument

Figure 11: Connect the mobile calibrator to the instrument shows the calibration setup.

1. Turn on the instrument using the ON/OFF key.
2. Set the following configurations:
   • Weighting curve: A (dBA)
   • Integration type: FAST
   • Measuring range: 50 ÷ 100dB
3. Insert the mobile calibrator SC05 into the instrument's microphone until it clicks, as shown in Fig. 11.
4. Switch on the calibrator, selecting 94dB at 1kHz sinusoidal frequency.
5. Insert the provided screwdriver into the trimmer (see Fig. 1, part 16) and adjust manually until the display shows "94.0".
6. Remove the calibrator from the microphone and switch it off.

6. Using Software SoundLink

The "SoundLink" software connects the HTA102 to a PC for real-time SPL recordings and data saving.

6.1. Minimum System Requirements

• Hardware: Pentium IV
• RAM memory: 32MB
• Output interface: USB ports
• CD-ROM reader: Present
• Screen resolution: 800x600 (16 bit)
• Operating system: Windows XP or higher

6.2. Installation of Software SoundLink and of USB Driver

1. Insert the installation CD-ROM into the PC.
2. Launch "SoundLink_setup.exe" and follow the installation prompts.
3. Install the USB driver by launching "CP210XCPInstaller_x86.exe" (32-bit) or "CP210XCPInstaller_x64.exe" (64-bit) from the CD-ROM.
4. Connect the instrument to the PC using COM3 or COM4 ports.

6.3. Main Characteristics of Software SoundLink

The initial screen of the launched program is shown below (see Fig. 12).

Figure 12: Starting screen of software SoundLink shows the software interface with options for real-time data, graph display, and data logging.

Main characteristics:

• Real-time display of instrument values.
• Setting of sampling interval for recording (DataLogger).
• Starting SPL recording and displaying data numerically/graphically.
• Data saving in TXT format and exporting to Excel (XLS).

For detailed usage information, refer to the SoundLink software's Help section.

7. Maintenance

7.1. General Information

Observe manual recommendations during use and storage to prevent damage or danger. Do not use in high humidity or high temperatures, or expose to direct sunlight. Always switch off the instrument after use. If storing for a long period, remove the battery to prevent leaks that could damage internal circuits.

7.2. Replacing the Battery

When the LCD displays the [Low Battery] symbol (?), the battery needs replacement.

[CAUTION] This operation should only be performed by expert technicians. Ensure the probe is removed from the input terminal before proceeding.

1. Switch off the instrument.
2. Remove the battery compartment cover (see Fig. 1, part 18).
3. Disconnect the battery from the connector.
4. Connect the new battery, paying attention to polarity.
5. Replace the battery compartment cover.
6. Dispose of old batteries responsibly in designated containers.

7.3. Cleaning the Instrument

Use a soft, dry cloth. Do not use wet cloths, solvents, or water.

7.4. End of Life

[Caution] The [End of Life Disposal] symbol (♻️) on the instrument indicates that the appliance and its accessories must be collected and disposed of separately and correctly.

8. Technical Specifications

8.1. Technical Characteristics

Accuracy is specified at 23°C ± 5°C with relative humidity <80%RH.

Measurement of Sound Pressure Level (SPL)

Integration

Analogue Output

Microphone

Microphone with ½" Electret condenser.

Reference Standards

• Noise measurements: IEC61672-1 Class 2
• EMC: IEC/EN61326-1

8.2. General Characteristics

Mechanical Characteristics

• Size (L x W x H): 260 x 65 x 50mm (10 x 3 x 2in)
• Weight (battery included): 280g (10 ounces)
• Mechanical protection: IP40

Power Supply

• Battery type: 1x9V alkaline battery IEC 6F22
• Low battery indication: [Low Battery] symbol (?) on the display
• Battery duration: Approx. 30 hours
• External power supply: 100-240VAC, 50/60Hz, 0.3A / 9VDC, 500mA
• Auto Power OFF: After 15 minutes' idling

Display

• Characteristics: 4 LCD, Custom, backlit, bargraph
• Display update: 2/s

Recordings

• Sampling interval: Selectable between 1s and 59s
• Memory: Max 32700 recordings can be saved internally.

Output connector

mini USB

8.3. Environmental Conditions for Use

• Reference temperature: 23°C ± 5°C (73°F ± 41°F)
• Operating temperature: 0°C ÷ 40°C (32°F ÷ 104°F)
• Allowable relative humidity: <90%RH
• Storage temperature: -10°C ÷ 60°C (14°F ÷ 140°F)
• Storage humidity: <75%RH
• Max operating altitude: 2000m (6562ft)

This instrument complies with Directive EMC 2014/30/EU.

This instrument satisfies the requirements of European Directives 2011/65/EU (RoHS) and 2012/19/EU (WEEE).

8.4. Accessories

8.4.1. Accessories Provided

• Portable calibrator SC05
• Wind screen protection
• Adjustment screwdriver
• USB cable
• CD-ROM with software SoundLink
• Tripod
• 9V battery, 2 pcs
• Power supply + 4 universal plugs
• User manual of the instrument
• User manual of calibrator
• Rigid transport case

9. Assistance

9.1. Warranty Conditions

This instrument is warranted against material or manufacturing defects, in compliance with general sales conditions. Defective parts may be replaced during the warranty period. The manufacturer reserves the right to repair or replace the product. Return transport to the After-sales Service or a Dealer is at the Customer's charge, but shipment must be agreed in advance. A report detailing the reason for return must accompany shipments. Use original packaging for returns; damage from non-original packaging is charged to the Customer. The manufacturer is not responsible for injury to people or damage to property.

The warranty does not cover:

• Repair/replacement of accessories and battery.
• Repairs due to incorrect use or use with non-compatible appliances.
• Repairs due to improper packaging.
• Repairs performed by unauthorized personnel.
• Modifications made without the manufacturer's explicit authorization.
• Use not specified in the instrument's specifications or manual.

The content of this manual cannot be reproduced without the manufacturer's authorization.

Products are patented and trademarks are registered. The manufacturer reserves the right to make changes to specifications and prices due to technological improvements.

9.2. Assistance

If the instrument malfunctions, check battery and cable conditions before contacting After-sales Service. If issues persist, ensure the product is operated according to this manual. For returns to After-sales Service or a Dealer, transport is at the Customer's charge, with shipment agreed in advance. A report stating the return reason must be included. Use original packaging; damage from non-original packaging is charged to the Customer.