Microphone & PreAmplifier Combinations

Type 4939-L-002  ¼-Inch Free-Field Microphone With Type 2669-L Preamplifier, 4 HZ TO 100 KHZ, 200 V Polarization

Type 4939-L-002 ¼-Inch Free-Field Microphone With Type 2669-L Preamplifier, 4 HZ TO 100 KHZ, 200 V Polarization

Type 4939-L-002 is designed for high-level and high-frequency measurements. By using stainless steel diaphragm and protection grid, the microphone is optimised to withstand rough environments and is capable of working at high temperatures up to 150°C (302°F).

USE SCENARIOS

  • High level measurements
  • High frequency measurements
  • Model work

THIS MICROPHONE IS A FACTORY-ASSEMBLED COMBINATION OF:

  • Microphone:  Type 4939
  • Preamplifier: Type 2669-L

The unit is assembled in a clean-room environment and sealed together, after which it is assigned one single type number and one single serial number. This means that the combined unit has better precision and long-time stability, and is handled as one complete unit.

The unit also contains TEDS, which means that information about the serial number, type and sensitivity is stored within it.

THE BENEFITS OF USING A MICROPHONE-PREAMPLIFIER COMBINATION ARE:

  • Better stability and precision. Because the unit is assembled in clean-room facilities, there is no contamination.
  • Ease of use. Your analyzer front-end and software will automatically detect the type number, serial number and sensitivity because of the built-in TEDS technology. There is no need to enter this manually for every channel.
  • Calibration integration. The TEDS technology means the microphone is automatically detected and identified by your data acquisition software, allowing it to be easily integrated with your calibration database.
  • Fewer errors. As your data acquisition software automatically knows the microphone type, serial number and sensitivity, manual inputs are greatly reduced – reducing human errors.

Capacitance: pF

Diameter: 1/4

Dynamic range: 35 – 164 dB

Frequency range: 4 – 100000 Hz

Inherent noise: 35 dB A

Lower limiting frequency -3dB: 4 Hz

Optimised: Free field

Polarization: Ext polarized

Polarization voltages: 200 V

Pressure coefficient: -0.007 dB/kPa

Sensitivity: 3.5 mV/Pa

Standards: IEC 61094-4 WS3F

Temperature coefficient: 0.003 db/ºC

Temperature range: -20 – 80 C

Venting: Side

Weight: gram

Sound field: Free-field

Input type: Classic

Microphone type: Free field