UHR GEOPHYSICAL SEISMIC RECORDER

INPUT CHARACTERISTICS

Number of Channels:

16 and 24 (Expandable in groups of 24)

Voltage Range Software Configurable:

±10V, ±1V, ±100mV or ±10mV.

Input Impedance:

2.0 Megohms line-line.

Common Mode Rejection:

95dB on lower ranges

Over voltage Protection:

±25 – Volt transients with power applied

A/D TRANSFER CHARACTERISTICS

Conversion Architecture:

24-Bit Delta-Sigma

Sample Rates:

0.4-105 kilosamples per second per channel in high-speed mode, 0.2-52 kilosamples per second in high-resolution mode.

Over sampling Factor:

x128 in high-resolution mode: x64 in high-speed mode.

DC Accuracy:

(Mean composite error after autocalibration)

Gain Range Accuracy:

±10V Range: ±1.0mv

±1V Range: ±0.3mv

±100mV Range: ±0.08mv

±10mV Range: ±0.02mv

Passband:

DC to typically 45 percent of the selected sample rate.

Passband Ripple:

±0.02dB maximum

Stopband threshold:

Typically 55 percent of the selected sample rate.

Stopband Attenuation:

98dB typical.

-3dB Bandwidth:

DC to typically 49 percent of the selected sample rate.

Integral Nonlinearity (INL):

0.001 percent of fullscale range; typical.

No Missing Codes:

24 Bits.

Dynamic Range:

103dB; typical in high-resolution mode, 100dB in high-speed mode.

Interchannel Crosstalk:

-96dB typical to 40kHz

Phase Skew:

Typically less than 100ns

Antialias Filtering:

Each ADC provides linear- phase digital lowpass filtering for “passband” and “stopband”. In addition to the didgitalfilter, a 2nd-order Butterworth lowpass analogue image filter in each channel provides a -3dB cutoff frequancy of approximately 150kHz to suppress images from the digital filter.