The Agilent 42841A is a bias current source for use with the Agilent E4980A or Agilent 4284A or Agilent 4285A. The configured measurement system has the capability to perform DC bias current measurements of up to 40 A in the 20 Hz to 2 MHz frequency range (with the E4980A) and up to 10 A in the 75 kHz to 30 MHz frequency range.