Charge Amp (Ar-Gxch) - Teac GX-1 Instruction Manual

Amplifiers

Charge Amp (AR-GXCH)

When pressure is applied to certain crystals, electrical polarization
occurs. This phenomenon is called a piezoelectric effect. From among
the acceleration transducers that use this piezoelectric effect, the elec-
trical-charge output type transducers are connected to the AR-GXCH.
In the SI system of units, the unit of acceleration is m/s2. However,
former measurements of acceleration using the gravity acceleration
unit G (9.80665 m/s
common, so the units for the AR-GXCH range are G with the units of
sensitivity being pC/G. The recorded data is also in G units. If you
want to record in m/s
G = 9.81 m/s 2 .
Filters
Analog Filter
The analog filter is an 8th order Butterworth low-pass filter (–48
dB/oct). The cutoff frequency can be selected independently of the
sampling frequency. To prevent aliasing, the cutoff frequency must be
set to 50% or less of the sampling frequency.
Digital Filter
The digital filter using a DSP can attenuate from 40% of the set sam-
pling frequency. The digital filter is not functional at sampling fre-
quencies of 200 kHz, 100 kHz, and 50 kHz.
Calibration
Gain self-calibration using a DSP is performed whenever power is
turned on. The startup period when the power is turned on is longer
than for other types of amps. The signal used for calibration is built
into the amp.
4-30
2 , shortened to 9.81 in the descriptions below) are
2 units, use Change Unit in GX Navi to specify 1