Models 2680M1-XXX through 2680M7-XXX charge amplifiers are designed for use with piezoelectric transducers and are suitable for airborne applications. Hybrid microcircuit construction results in small size,
ruggedness and low power consumption. The airborne charge amplifiers have an output voltage proportional to the input charge. As a result, the amplifier sensitivity is not appreciably affected by the capacitance
of the input cable.
The use of modular construction techniques permits great versatility in gain and filter choices. This unit
has two outputs, a biased output and an unbiased output. Both outputs are adjustable with a common gain
control. The M1 through M7 defines the charge gain per Table 1.
The -XXX describes the upper cutoff frequency (-5% point) per Table 2. For example, a -101 has a low pass
filter which is flat up to 100 Hz, a -502 has a low pass filter which is flat up to 5000 Hz.
The following performance specifications conform to ISA-RP-37.2 (1964) and are typical values, referenced at +75˚F (+24˚C) and 100 Hz,
unless otherwise noted. Calibration data, traceable to National Institute of Standards and Technology (NIST), is supplied.