Musktool-HY114 Class 2 IEC 61672-1:2013 Class 2 and GB/T 3785.1-2023 Class 2.Digital sound level meter

Introduction

Specifications

The electroacoustical performance specifications of HY114 are listed below.

a) Performance category

IEC 61672-1:2013 Class 2 and GB/T 3785.1-2023 Class 2.

b) Classification group for susceptibility to radio frequency fields

IEC 61672-1:2013 and GB/T 3785.1-2023 Group X.

c) Frequency weighting

A and C.

d) Time weighting

F (Fast response).

e) Normal model of operation

With no windscreen and dustproof device, microphone is fit directly.

f) Normal operational environmental conditions

－ air temperature     0℃～40℃;

－ relative humidity   25 %～90 %;

－ static pressure     65 kPa～108 kPa.

g) Reference environmental conditions

－ air temperature    23 ℃;

－ relative humidity   50 %;

－ static pressure     101.325 kPa;

－ no strong mechanical vibration, shock, presence of strong electromagnetic fields and corrosive gases around.

h) The model of microphone

12.7 mm (½˝) prepolarized condenser microphone Type HY205, Class 2, free field frequency response (typical frequency response of HY205 see Fig. 1).

                                                                                   Fig. 1  Frequency response of Microphone Type HY205

The microphone reference point is the geometrical center of the diaphragm of microphone.

Nominal sensitivity is 40 mV/Pa (nominal sensitivity level is -28 dB, re. 1V).

Cartridge capacitance is about 15 pF。

i) Detector and display device

True RMS wave detector with dynamic range 60 dB.

Dot-matrix liquid crystal display(128x64) with 0.1 dB display resolution. Data update cycle is 1 s. Resolution of analog indicator is 1 dB, while update cycle is 0.1 s. Meanwhile, overload, under range, battery status, maximum holding flag and unit of measurement can be displayed.

j) The total ranges of A- and C-weighting sound level that can be measured at 1 kHz

A-weighting sound level is 30 dB to 130 dB, divided into three range:

－ Low:  30 dB to 90 dB;

－ Mid:  50 dB to 110 dB；

－ High:  70 dB to 130 dB.

C-weighting sound level is 40 dB to 130 dB, divided into three range:

－ Low:  40 dB to 90 dB;

－ Mid:  50 dB to 110 dB;

－ High:  70 dB to 130 dB.

k) Directions

The directions of HY114 Sound Level Meter at 1 kHz , 2 kHz , 4 kHz and 8 kHz are shown in

Fig. 2.

              Fig. 2   The directions at different frequence

l) Power supply

Powered by 4 batteries of R6P/LR6. Continuous operating time in reference environmental conditions can be 6h when using R6P, or 30h using LR6. The maximum operating current is less than 75mA.

Battery flag on the LCD is full when the voltage is higher than 5.0 V, and will be empty and blinking when lower than 4.0 V.

Could show the power voltage when power-on.

Also can be powered by external DC supply of type HY9214, its nominal voltage is 5V or 6V.

m) Calibration check frequency

1 kHz.

n) The model of Acoustic Calibrator which is used to check and calibrate the Sound Level Meter.

Type HY603 or other Acoustic Calibrator that applies to the 12.7 mm microphone.

o) Effect due to use windscreen

Shall not exceed 0.5 dB over important frequency range.

p) Reference direction

Sound-incidence direction is perpendicular to microphone diaphragm (0º incidence).

q) Reference level range

“Mid” position (50 dB～110 dB).

r) Reference sound pressure level

94 dB re. 20 μPa.

s) Warm-up time

2 min.

t) Anticipated Self-generated noise level

The highest self-generated noise level anticipated for A-weighting is 25 dB and 35 dB for C-weighting at reference environmental conditions.

u) Analog output

AC linear voltage: 110 mVrms refer to the upper limit of each range.

DC logarithmic voltage: 15 mV/dB, 450 mV to 1950 mV refer to all three ranges, ie 450 mV to the lower limit, 1950 mV to the upper limit.

Used a 3.5 mm 2-ch earphone socket for output, its minimum impedance with load is 10kΩ.

v) Digital output

RS232 serial interface, output ASCII code. Baud rate is 300 bd. It can be set to 9600 bd for special request. Also Used a 3.5 mm 2-ch earphone socket for output.

w) Effect of temperature

The deviation of the sound level displayed at any temperature from the sound level displayed at the reference air temperature shall not exceed ±1.0 dB over the range of air temperature from 0℃ to 40℃.

x) Effect of humidity

The deviation of the sound level displayed at any relative humidity from the sound level displayed at the reference relative humidity shall not exceed ±1.0 dB over the range of relative humidity from 25% to 90%.

y) The limits of temperature and humidity may be causing damage to the sound level meter

－ -20℃, +60℃;

－ 95％RH.

z) The adjustment data to obtain equivalent free field response

The sound pressure response produced by the calibrator of Type HY603 or electrostatic acuator must be adjusted to obtain equivalent free field response. See Table 1.

Table 1  Adjustment data to obtain equivalent free field response

aa) The electrical impedance replaced microphone for test

15 pF in series with 10 Ω.

ab) The highest sound pressure level applied to the microphone without causing damage

146 dB.

ac) The maximum peak-to-peak voltage applied to the electric input

30 V.

ad) The range of supply voltage

4 V ～ 6.5 V.

ae) Overall dimensions

HY114: Length 256 mm, Width 74 mm, Depth 25 mm

HY114A: Length 276 mm, Width 74 mm, Depth 25 mm

Detailed see Fig. 3.

af) Weight

HY114  ：about 480 g;

HY114A ：about 500 g (not include extension cable). 

Fig. 3  Dimensions of HY114