Extech 407750 Operating Manual

User's Guide

Digital Sound Level Meter Model 407750

Warranty

EXTECH INSTRUMENTS CORPORATION warrants this instrument to be free of defects in parts and workmanship for one year from date of shipment (a six month limited warranty applies on sensors and cables). If it should become necessary to return the instrument for service during or beyond the warranty period, contact the Customer Service Department at (781) 890-7440 ext. 210 for authorization or visit our website at www.extech.com (click on ‘Contact Extech’ and go to ‘Service Department’ to request an RA number). A Return Authorization (RA) number must be issued before any product is returned to Extech. The sender is responsible for shipping charges, freight, insurance and proper packaging to prevent damage in transit. This warranty does not apply to defects resulting from action of the user such as misuse, improper wiring, operation outside of specification, improper maintenance or repair, or unauthorized modification. Extech specifically disclaims any implied warranties or merchantability or fitness for a specific purpose and will not be liable for any direct, indirect, incidental or consequential damages. Extech's total liability is limited to repair or replacement of the product. The warranty set forth above is inclusive and no other warranty, whether written or oral, is expressed or implied.

Introduction

Congratulations on your purchase of the Extech 407750. This device measures sound level in dB and the measurement range can be set automatically or manually. The 407750 offers selectable frequency weighting (‘A’ and ‘C’) and Time Response (Fast and Slow). The built-in RS-232 PC interface allows the user to record readings onto a PC in real-time. Careful use of this meter will provide years of reliable service.

Specifications

Display Backlit 2000 count LCD with analog bargraph Display update rate Main LCD digits: 0.5 seconds; Bargraph: 50mS Analog Bargraph 1dB steps with 50dB display range Microphone Electret condensor (0.5” diameter) Measurement Bandwidth 31.5Hz to 8KHz Measurement Range A weighting: 30 to 130dB; C weighting: 35 to 130dB

6 ranges in 10 dB steps: 30 to 80dB, 40 to 90dB, 50 to

100dB, 60 to 110dB, 70 to 120dB, 80 to 130dB Accuracy / Resolution ± 1.5dB / 0.1dB Time response selections Fast (125ms) and Slow (1 second) AC and DC Analog outputs 0.707VAC rms at full scale; 10mVDC / dB;

3.5mm output jacks Standards Meets ANSI and IEC Type 2 External Calibrator Extech models 407766 or 407744 Power 9V Battery; 20 hour battery life (typical) with low battery

Dimensions/weight 3.2 x 10.1 x 1.5” (80 x 256 x 38mm) / 8.5 oz. (240g)

indication

Model 407750 Version 2.1 February 2004

Meter Description

1. LCD Display

2. Microphone

3. ON/OFF key

4. REC (Record) key

5. MAXHLD (Max Hold) key

6. C/A Weighting Select key

7. BA (Background Absorber) key

8. F/S Fast / Slow Response select key

9. DOWN

10. Backlit (LCD backlighting) key

11. UPPER

12. AC adaptor jack

13. Calibration screw adjust

14. AC analog output jack

15. DC analog output jack

16. RS-232 output jack

Note: The Battery Compartment and the Threaded Tripod mount access are located on the back of the instrument (not pictured)

Model 407750 Version 2.1 February 2004

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