The DF-A0157 is a high-speed, 4-band switch intended for direction finding applications. It accepts four frequency bands, each with five antenna elements, and outputs the elements of any one band to the corresponding five RF outputs.

The switch is controlled via an RS-485 serial interface to allow remote control over a distance of up to 500m. All switching is solid state for rapid and unlimited switching cycles.

The DF-A0157 includes an internal noise source as well as an external input for chain calibration purposes. Either the internal noise source or the external calibration input may be selected to simultaneously inject a balanced signal in place of the antenna inputs and thereby correct errors caused by variations in the system’s RF path.

DF-A0157 Features

DF Switch

  • 4-band switch
  • External injection mode for chain calibration
  • Internal chain calibration noise source, selectable with either inline amplifier or with the amplifier bypassed.
  • Low noise amplifier on each channel with passive bypass capability
  • High-speed solid state switching


  • Single-channel amplifier
  • Low noise pre-amplifier on input
  • DC-injection to power upper stages

Advanced input stages:

  • ESD protection

Advanced output stages:

  • Output amplifiers for long cables
  • Cable slope correction
  • ESD protection