ANT/4 Magnetic Antenna

DESCRIPTION

The ANT/4 is a low-noise magnetic field sensor designed for magnetotelluric investigations and other applications where measurements of the field at frequencies below 1 Hz are required. Using Triple-Nested magnetic feedback amplifier technology and including carefully designed mu-metal cores, this antenna is designed to be a highly flexible instrument, built to withstand the difficult conditions encountered in the field environment.


SPECIFICATIONS FOR THE ANT/4 MAGNETIC ANTENNA

Dimensions:

  • Length: 138.0 cm (54.0 in)
  • Diameter: 4.8 cm (1.875 in)
  • Weight: 6.2 kg (13.5 lb)

Power Specifications:

  • Power requirement: Internal batteries 2 x 9V, or external power ± 7.5 V to ± 15 V, 4.5 mA approximately 125 hours run time with batteries.
  • Inrush current: With external power supplies is less than 25 mA for 5 ms

Output Specifications:

  • Output: Differential analog output, 24 to 56 Vpp depending on Supply voltage. Will drive 300 m (1000 ft) or longer cable ± 4 mA max load.

Frequency Specifications:

  • Frequency Range: 0.0001 – 1000 Hz
  • Sensitivity in Passband: 100 mV/ (100 mV/nT)
  • Highpass: 0.25 Hz, 1 pole filter, useful down to 10,000 seconds.
  • Lowpass: 1 kHz, 3 pole filter

Noise Level:

  • 100 (100 fT) per Hz at 1 Hz
  • 12 (12 fT) per Hz nominal > 1 Hz

Application: MT / CSEM


OPTIONS

Highpass can be set down to 0.01 Hz at an extra cost of $400.

The following parameters can be adjusted to customer requirements at no extra cost:

  • Highpass can be set as low as 0.05 Hz.
  • Lowpass can be set as low as 10 Hz and up to 1200 Hz
  • Output sensitivity can be set between 10 mV to 500 mV/g. 500 mV/g would be used for seafloor applications.

Response:

ANT/4 Magnetic Antenna

Supporting Documents

Download Specification sheet for ANT-4