Features

General

The Samtec 2 receiver features up to five simultaneous channels, plus two more optional channels that may be used to monitor the magnetic field for remote reference data acquisition. Each channel has its own A/D converter and real time dynamic gain ranging. An internal reference pulse for both E and H sensors allows confirmation of system calibration.

Frequencies are measured at 18 preset values, in three frequency bands (low, middle, and high), for a total of 54 frequencies that may be measured. Fiber optic cable is used to connect the receiver to a PC through an interface unit called the IMT. The IMT may be used to store data, or can pass data directly to a PC.

The PC is used to control the system, monitor data quality as it is collected, and to process data. This includes management of time series data files containing 1024 samples for each channel. The following parameters may be displayed in real time during acquisition: resistivity, tipper phase, coherencies, amplitude spectrum, time series, skew, ellipticities, strike, and rotation angle.

Three magnetic sensors are available to cover the AMT and MT ranges. Each of these sensors has an internal calibration coil. The electric sensors consist of low noise nonpolarizable Pb-PbCl electrodes with battery powered preamplifiers connected to twenty meter electric lines.

Specifications

Multichannel Unit (MCU)

The MCU unit receives the signals coming from the sensors, It acquires data on three to five bands of 18 preset frequencies each.

One analog to digital converter per channel (14 bit)

Real time "dynamic gains" for high dynamic range

Low noise amplifiers and filtering 8 bits CMOS microprocessor remote controlled

On Site Test with internal noise generator of complete system with E and H sensors.

Supplied by standard 12V 40Ah car battery: 12V/1.4A (typically) for 5 channels with sensors

Galvanometer for supply voltage measurement

Weatherproof casing

High speed serial link by optical cable.

PC Interface Unit (IMT)

The IMT unit is an interface module between MCU unit and a PC computer. The PC computer initializes the IMT, but does not need to be connected to the IMT during the acquisition. The IMT unit can store up to 8 Mbytes of time series data.

Direct interface to high speed Samtec 2 optical link and PC computer (RS 232C serial link)

Acquisition management with Samtec 2 MCU

Internal real time clock

Time series data transfer in IMT internal memory or directly from MCU to PC computer in transparent mode

Battery voltage and communication control with galvanometer and LED

Memory: 384 data records of 1024 time series samples for each channel, and additional information, with 4 Mbytes backup memory board.

Weight: 2kg with six 1.5V size dry cells

Temperature Range: 0 - 50øC (-20øC to +70ø optional) IMT PC Software

Management of magnetotelluric acquisition and computation of geophysical parameters from time series.

Management of IMT and PC time series data files

Management of PC result files

Management of PC to IMT serial link

Standard magnetotelluric parameters computation using cascade decimation and impedances estimation

Display of time series data, geophysical results (resistivities, tippers, strikes, skews) and other results (coherencies, amplitudes,...) Easy to use menus with help file.

Sensors

Electric Line

Standard 20m long electric line

Low noise electric cable

Low noise Pb-PbCl electrodes

Low noise differential amplifier

5 kg complete electric system

CMA magnetic sensor

Frequency range: 1Hz - 7500Hz

Sensitivity: 100mV/g

Length: 1.2m

Diameter: 9cm

Weight: 22kg CMB magnetic sensor

Frequency range: 1Hz - 7500Hz

Sensitivity: 100mV/g

Length: 1m, Diameter: 9cm

Weight: 22kg

CMC magnetic sensor

Frequency range: 0.0005Hz - 400Hz

Sensitivity: 10 to 1000mV/g

Length: 1.2m

Diameter: 10cm

Weight: 22kg

Standard Components

Samtec 2 unit with 3 CMB sensors, Electrice field sensors, 50m long optical cable, IMT interface, and instruction manuals.

Ordering Information

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