ANALOG SOUND LEVEL METER 92282 ASSEMBLY AND OPERATING INSTRUCTIONS 3491 Mission Oaks Blvd., Camarillo, CA 93011 Visit our Web site at http://www.harborfreight.com Copyright 2004 by Harbor Freight Tools. All rights reserved. No portion of this manual or any artwork contained herein may be reproduced in any shape or form without the express written consent of Harbor Freight Tools. For technical questions and replacement parts, please call 1-800-444-3353
Specifications Min/Max. Decibel Measurements 50-126 db (7 Range Settings) Accuracy + / - 2 db @ 114 db A-Weighted Reading 500 to 10 KHz (Frequency) C-Weighted Reading 30 to 10 KHz (Frequency) Features: Built-in 5/8 Dia. Microphone, 9 Volt Battery Included, Fast and Slow Response Settings, Output Jack (to connect to test equipment or home theatre),1/4-20 Threaded Insert for Tripod Mount. Save This Manual You will need the manual for the safety warnings and precautions, assembly instructions, operating and maintenance procedures, parts list and diagram. Keep your invoice with this manual. Write the invoice number on the inside of the front cover. Keep the manual and invoice in a safe and dry place for future reference. Safety Warnings and Precautions WARNING: When using tool, basic safety precautions should always be followed to reduce the risk of personal injury and damage to equipment. Read all instructions before using this tool! 1. Keep work area clean. Cluttered areas invite injuries. 2. Observe work area conditions. Do not use electric products in damp or wet locations. Don t expose to rain. Keep work area well lighted. Do not use electrically powered tools in the presence of flammable gases or liquids. 3. Keep children away. Children must never be allowed in the work area. Do not let them handle the Sound Level Meter. 4. Store idle equipment. When not in use, the Sound Level Meter must be stored in a dry location to inhibit rust. Always lock up tools and keep out of reach of children. 5. Use the right tool for the job. Do not attempt to force a small Sound Level Meter to do the work of a larger industrial Sound Level Meter There are certain applications for which this tool was designed. It will do the job better and more safely at the rate for which it was intended. Do not modify this tool and do not use this tool for a purpose for which it was not intended. 6. Dress properly. Protective, electrically non-conductive clothes and non-skid footwear are recommended when working. Wear restrictive hair covering to contain long hair. 7. Use eye and ear protection. Always wear ANSI approved impact safety goggles. Use appropriate ear protection when testing. Make sure children, pets, and all bystanders are clear of the area when testing. High volume testing can result in permanent hearing damage without proper ear protection. 8. Maintain tools with care. The unit must be kept clean, dry, and free from oil and grease at all times. Page 2
9. Disconnect power. Remove the battery when not in use for a week or more. Leave the Range Selector in the Off position when not in use (to conserve battery power). 10. Stay alert. Watch what you are doing, use common sense. Do not operate any tool when you are tired. 11. Check for damaged parts. Before using the Sound Level Meter, any part that appears damaged should be carefully checked to determine that it will operate properly and perform its intended function. Check for alignment and binding of moving parts; any broken parts or mounting fixtures; and any other condition that may affect proper operation. Any part that is damaged should be properly repaired or replaced by a qualified technician. Do not use the tool if any switch does not turn On and Off properly. 12. Guard against electric shock. Prevent body contact with grounded surfaces such as pipes, radiators, ranges, and refrigerator enclosures. 13. Do not operate the Sound Level Meter if under the influence of alcohol or drugs. Read warning labels if taking prescription medicine to determine if your judgment or reflexes are impaired while taking drugs. If there is any doubt, do not operate the tool. 14. Maintenance. For your safety, service and maintenance should be performed regularly by a qualified technician. 15. Pacemaker safety warning. People with pacemakers should consult with their physician(s) before using this product; operation of equipment in close proximity to a heart pacemaker could cause interference or failure of the pacemaker. Warning: The warnings, cautions, and instructions discussed in this instruction manual cannot cover all possible conditions and situations that may occur. It must be understood by the operator that common sense and caution are factors which cannot be built into this product, but must be supplied by the operator. Unpacking When unpacking, check to make sure the parts shown on page 7 are included. If any parts are missing or broken, please call Harbor Freight Tools at the number on the cover of this manual as soon as possible. Page 3
Introduction Designed to measure sound intensity in acoustic environments, this Sound Level Meter works in continuous or intermittent, loud or soft, high/low pitched, or broadband conditions. Examples of usage areas include home theatre installations, factories, offices, schools, airports, auditoriums, and studios. You may connect directly to home theatre systems or external test equipment using the output jack (see Assembly Drawing on page 7). A and C weightings allow you to check compliance with safety regulations while analyzing area acoustics. Slow and Fast Response Settings check peak and average noise levels. Operation Refer to the Assembly Drawing on page 7. FIGURE 1 Installing the Battery This unit comes with a 9 Volt battery. To install or replace, use a Phillips head screwdriver (not included) to remove the screw on the battery compartment as shown in FIGURE 1. Remove the old battery, and replace it with a new one, making sure that the positive (+) and negative (-) battery terminals match polarity markings in the unit. Replace the back panel. Testing the Battery To test the battery, set the RANGE to BATT. If the meter shows a reading in the red BATT TEST region, the battery is still good. If the reading is out of the red BATT TEST region, it means you need to change the battery. When finished, to save power, set the RANGE to OFF. Remove the battery if you are not using the unit for more than a week. See FIGURE 2. FIGURE 2 Good Battery Area Page 4
Operation (continued) How the RANGE selector works. You can select one of seven sound level ranges, each containing 16 different ranges (see FIGURE 3). Each number on the range number refers to the mid-point of each range. The needle point on the scale (see FIGURE 2) shows the actual sound level, displaced from the mid-point. For example, If you set the range to 90, and the meter scale reads -3, the actual sound level is 87 (at value where the RANGE is set). FIGURE 3 7 Ranges Taking Sound Measurements. Never hold the Meter directly between you and the sound source. Doing so may produce an error (of several decibels) in the frequency range above 100 Hz. Position the Meter as if there were an imaginary line between you and the Meter, and the line is perpendicular to a line between the meter and the sound source. See FIGURE 4 below. FIGURE 4 Sound Source Imaginary Line Meter YOU Imaginary Line Note: Handle the Meter carefully. The fragile internal movement and microphone will be damaged if dropped. Never operate the Meter at a range setting that causes the needle to Peg back and forth. Pegging may damage the meter scale. 1. If you want to measure short bursts of sound, or peak values, set the RESPONSE to FAST. If you want to measure average sound levels, set the RESPONSE to SLOW. 2. To measure noise level, set the WEIGHTING to A. Set the WEIGHTING to C to measure sound levels of musical material. Note: In the A position, the Meter measures frequencies in the 500 to 10 KHz frequency. In the C position, the Meter measures in the 30 to 10 KHz frequency. Page 5
Operation (continued) 3. Set the RANGE to the highest setting (120 db) and then adjust it down until there is a significant deflection of the needle. Always use the lower of any two possible settings. For example, If the RANGE is set at 90 db and the Meter reads around -5, reset the Range to 80 db so that the Meter reads +3 for an actual sound level of 83 db. Note: For an accurate reading, any sound that you measure must be at least 10 db louder than the background noise level. Note: For the best reading, point the Microphone toward the sound source. Use the following chart to determine the acceptable level of noise: Extracted from the U.S. Dept. of Labor Noise Regulations Using the Tripod Adapter You can mount the Meter on a standard tripod (1/4-20 thread) to help eliminate hand noise and noise reflected off of your body. It is also preferable to use a tripod when using external recording or test equipment. Calibration Although the unit comes pre-calibrated from the factory and should not need further calibrating, it may become necessary in the future. If so, take the unit to an authorized audio professional, who can recalibrate the unit by inserting special equipment into the CAL hole on the side of the unit. See page 7. Maintenance 1. Keep the unit clean and dry. Wipe it off with a lint free cloth after each use. 2. Remove the batteries if you are not using the unit for over a week. 3 Store the unit in a dry location. Do not let it freeze or sit in direct sunlight. Page 6
Assembly Drawing Microphone Calibration Hole (only to be accessed by an authorized audio professional) Range Selector Weighting Selector Response Selector Output Jack Scale Battery Compartment (Access on back of unit) No Replacement Parts Available For This Unit PLEASE READ THE FOLLOWING CAREFULLY THE MANUFACTURER AND/OR DISTRIBUTOR HAS PROVIDED THE PARTS DIAGRAM IN THIS MANUAL AS A REFERENCE TOOL ONLY. NEITHER THE MANUFACTURER NOR DISTRIBUTOR MAKES ANY REPRESENTATION OR WARRANTY OF ANY KIND TO THE BUYER THAT HE OR SHE IS QUALIFIED TO MAKE ANY REPAIRS TO THE PRODUCT OR THAT HE OR SHE IS QUALIFIED TO REPLACE ANY PARTS OF THE PRODUCT. IN FACT, THE MANUFACTURER AND/OR DISTRIBUTOR EXPRESSLY STATES THAT ALL REPAIRS AND PARTS REPLACEMENTS SHOULD BE UNDERTAKEN BY CERTIFIED AND LICENSED TECHNICIANS AND NOT BY THE BUYER. THE BUYER ASSUMES ALL RISK AND LIABILITY ARISING OUT OF HIS OR HER REPAIRS TO THE ORIGINAL PRODUCT OR REPLACEMENT PARTS THERETO, OR ARISING OUT OF HIS OR HER INSTALLATION OF REPLACEMENT PARTS THERETO. NOTE: Some parts are listed and shown for illustration purposes only and are not available individually as replacement parts. Page 7