GMR 540V DC/DC Converter


  • Max. DC bus voltage: +/- 270V DC
  • Capacitance: 0.054 F
  • Charge current: +/- 1 A
  • Power supply: two 12V batteries


  • Auto shut-off
  • Analog voltmeters on panel


GMR 4800V Transmitter

Performance Specs:

  • Max. transmit voltage: 4800V AC
  • Max. transmit current: 600A, 25 A*s
  • Instrument dead time: <5ms
  • 4 identical transmit/receive channels (expandable to 8 or 12)
  • Receiver input noise: <500 pV/rt(Hz)
  • 24-bit wideband simultaneous sampling
  • Pulse sequences for FID (single-pulse),T1 (90-90 pulse),and T2 (CPMG and spin echo) acquisition with phase-cycling.

Safety Feature:

  • Auto-shut down in overcurrent state.

GMR Tuning Unit

Performance Specs:

  • Max tuning capacitance 15.5μF (expandable to 31.5μF)
  • Max. transmit voltage: 4000V AC
  • Max. transmit current: 600A
  • Adjustable by 0.5μF increments for fine tuning

Safety Features:

  • System will not operate unless tuning cover is securely closed
  • Rapid discharge (time constant ~ 1s)
  • Keyed access to high-voltage contacts

Software and Accessories

Standard Accessories and Software:

  • High voltage environmental-rated connectors with carrying case
  • GMR data acquisition software
  • GMR noise cancellation software
  • GMR 1D inversion software

Optional Software:

  • GMR 2D inversion software

Surface Wire Options:

  • #8 AWG, 4kV polyurethane insulated
  • #10 AWG, 4kV polyurethane insulated

Expansion Options

  • 4-channel Transmit/Receive Expansion Module (for accelerated 2D imaging)
  • 4-channel Receive Expansion Module
  • Two parallel DC DC Converters (for extended pulse output)
  • 16uF Tuning Expansion Module (for use at low Earth latitudes)
  • Custom ATA shipping cases