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The 130E20, 130E21, 130E22 and 130A23 Microphones (Figure 1) are all Array Microphones
with integral preamplifiers. These Microphones are 7mm in diameter and have a dynamic range
up to 122dB. The 130E20 includes a BNC Jack, 130E21 includes a 10-32 Coaxial Jack, and the
130E22 and 130A23 both include a SMB Coaxial Socket. All 130 series Microphones are
Prepolarized. By applying a high temperature polymer material, which contains frozen electrical
charges, to the top of the backplate, PCB has eliminated the need for external Polarization. This
saves you money and time.
The 130 Series Array Microphones have the following Features:
Lower per Channel Cost
Use ICP
Sensor Power
Prepolarized
Reduce Test Time
Increase Data Consistency
Integrate with Signal Conditioners
Includes TEDS compliant with IEEE
1451.4
With their integrated ICP
preamplifier and Prepolarization, these microphones can be powered
by simple, inexpensive, constant-current Signal Conditioners. These units are easy to operate,
and they interface with many standard signal analysis, data acquisition and recording
instruments. They utilize low-impedance cable on which signals can be driven long distances
with minimal signal loss.
3.0 Powering
All ICP
powered microphones require correct constant-current excitation for proper operation.
For this reason, use only PCB constant-current signal conditioners or other approved constant-
current sources. The signal conditioner consists of a regulated, 18-30 VDC source. The power is
regulated by a current-limiting circuit, which provides the constant current excitation required
for proper operation of the ICP
Microphone. In general, battery powered devices offer
versatility for portable low-noise measurements, whereas line-powered units provide the
capability for continuous monitoring. A typical system schematic is shown in Figure 2.
Figure 2
Certain models of signal conditioners have meters or LEDS, which enable users to monitor the
bias voltage output signal, check microphone operation, and detect cable faults. Normally, a
“yellow” reading indicates an open circuit (example: a cable disconnected); “green” indicates
normal operation and a “red” reading indicates a short circuit (example: a shorted cable). The
Note
: Under no circumstances should
a voltage be supplied to an ICP
microphone without a current-
regulating diode or equivalent
electrical circuit. This may include
ohmmeters, multi-meters and
continuity testers. Damage to the
built-in electronics resulting from the
application of incorrect power, or the
use of an unapproved power source, is
NOT covered under warranty.
Microphone
Signal
Conditioner
Readout
Summary of Contents for 130E22
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