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These microphones all have the same performance specifications but are fitted with different
electrical connectors to make them suitable for differing applications.
Model 130F20 features a
BNC connector while Model 130F21 uses a 10-32 coaxial jack connector. Model 130F22
terminates in a SMB connector.
These m
odels are shown in Figure 1.
The 130A23 and 130A24 are designed for high amplitude applications with an upper dynamic
range of 150 dB. Model 130A23 terminates in a SMB electrical connector. The 130A24 is an
enhanced, rugged, water and dust resistant design, and terminates in a BNC electrical connector.
Model 130A24 has a lower sensitivity (10 mV/Pa) than the 130A23 (14 mV/Pa), but otherwise
the performance specifications are the same.
All 130 Series array microphones include TEDS capable digital memory and communitation
electronics compliant with IEEE 1451.4. These microphones are easy to operate and interface
with many PCB® ICP® constant current signal conditioners and other data acquisition and
recording instruments available on the market today. In a complete microphone system, low-
impedance cables couple the microphone and signal conditioner to customer supplied read-out
instruments. The use of low impedance cables enables signals to be driven long distances with
negligible signal loss.
3.0 Powering
All ICP
powered microphones require 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 provides an AC-coupled output signal that is compatible with
most standard readout devices. Signal conditioners consist of a regulated 2-20mA, 18-30 VDC
source. They are available in single or multi channel, battery or line powered configurataions.
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
Signal conditioners have meters or LEDS, which enable users to monitor the bias voltage output
signal, check microphone operation, and detect cable faults. Typically yellow denotes an open
circuit; green indicates normal operation and red indicates a short circuit. Many FFT analyzers,
data acquisition modules, and data collectors have the proper constant-current excitation built-in
for direct use with ICP
microphones. Before using this feature, care should be taken to assure
the proper supply voltage and constant current excitation are provided. Check the enclosed
specification sheet to make sure the supply voltage and current are within acceptable limits for
your particular microphone.
Signal
Conditioner
Data Acquisition
Microphone
