The Model 440 is a sensitive digital picoammeter with nine ranges from 100 picoamperes to 10 milliamperes full scale plus 100% overranging. FEATURES: Stability- Zero drift with time is less than 1 digit per day; drift with temperature is less than one digit per °C, making frequent adjustment unnecessary. Overload Protection. A transient overload of 1000 volts or a continuous overload of 600 volts at up to 20 mA will not damage the instrument. Damping. A front panel DAMPING control provides additional damping of noisy signals on the 100 nanoampere to 100-picoampere ranges. Digital Display. The digital display provides 3 digits with 0,1 picoampere resolution. Variable Display Rate. A front panel DISPLAY RATE control adjusts from 24 readings/sec. to 2 readings/minute to accommodate the mode of data retrieval. Optional BCD Output and Control Lines. Model 4401 Printer Output Cards are available as an accessory for factory or user installation. This option provides BCD outputs for significant digits, range , polarity, zero check, and overrange. Various remote control lines are also provided. The Output Buffer cards are easily inserted into prewired, prenmounted, card-edge connectors on the Model 440 chassis.