Extech 407738 Professional Digital Sound Level Meter with Memory
This unit was sparingly used and remained in storage. The unit is in excellent condition and works great. It comes with the carrying case, calibration screwdriver, instruction sheet and 3.5mm analog output jack as seen in the pictures.
Compliance: ANSI S1.4-1983: type 2; EN 651
Display: LCD
Description: Digital Sound Level Meter with Memory
Specifications & Description
Type 2 meter with manual data store and recall of up to 99 readings
High accuracy meets ANSI and IEC type 2 standards
Wide 26dB to 130dB range
Memory to store and recall up to 99 readings
Max/min recording with elapsed time stamp
A&C weighting
Fast and slow response
Large LCD display with analog bargraph
AC and DC analog output
Measurement Functions
Primary Functions Sound Pressure Level
Maximum Sound Level
Minimum Sound Level
Total range 26 to 130dB (32 to 130dB for ‘C’ weighted measurements)
Maximum level 130dB
Accuracy ± 1.5dB (under reference conditions)
Noise floor ‘A’ weighting: 26dB
‘C’ weighting: 32dB
Calibration signal 94dB at 1kHz (sinusoidal)
Range selections 26 to 80, 30 to 90, 40 to 100, 50 to 110, 60 to 120, 70 to 130
Frequency range 31.5 to 8000 Hz
Frequency weighting ‘A’ and ‘C’
Time weighting Fast (125ms) and Slow (1 second) Response
Notes on ‘A’ and ‘C’ Frequency Weighting
Use the ‘A’ and ‘C’ buttons to select ‘A’ or ‘C’ frequency weighting. With ‘A’ weighting selected, the frequency response of the meter is similar to the response of the human ear. ‘A’ weighting is commonly used for environmental or hearing conservation programs such as OSHA regulatory testing and noise ordinance law enforcement.
‘C’ weighting is a much flatter response and is suitable for the sound level
analysis of machines, engines, etc.
Most noise measurements are performed using 'A' Weighting
and SLOW Response.
Notes on ‘FAST’ and ‘SLOW’ Response Time
Use the FAST and SLOW buttons to select a FAST (125 ms) or a SLOW (1 second) response time. Select FAST to capture noise peaks and noises that occur very quickly. Select the SLOW response to monitor a sound source that has a consistent noise level or
to average quickly changing levels. Select SLOW response for
most applications.