For general purpose dc or pulsed measurement, use the HP 41421B source monitor unit.  The equivalent of 4 instruments, this precision module forces voltage up to ± 100 V and simultaneously measures currents down to 20fA.  It can also force currents up to ± 100 mA while measuring voltage down to 40 µV.

• The HP Agilent 41421B is a used Source Monitor Unit Plug the for 4142B.
• Ranges: 100 microvolt to 100V range
• Current up to 100 mA