Model 70A is a full featured, wideband, differential instrumentation amplifier that can be used for a variety of applications. Designed to condition, amplify and filter low level analog signals it is used for data acquisition, analog recording, line driving, data filtering and signal isolation.
The basic element is a very stable, low noise differential amplifier with wideband response. Input impedance is 50 Megohms, linearity is 0.01% and common mode rejection is 130 dB for up to 300 Volts. Bandwidth exceeds 100 kHz for gains from 1 to 1000.
Eleven switch selectable gains and a variable gain multiplier provide continuous coverage from 1 to 5,000. Gain accuracy is ±0.1% with ±0.02% available as an option. The 70A-5 has a two pole, switch selectable, low pass filter with Bessel response. The 70A-6 is the same, but with six pole Bessel response. Butterworth response is also available.Model 70A provides two independently buffered ±10 Volt full scale outputs each with 100 milliampere drive current. Output impedance is less than 0.1 Ohm for driving long lines and capacitive loads. Output is short circuit protected and current is limited to safeguard external equipment.
Front panel switches select gain step, calibrated or variable gain and filter frequency. Multiturn screwdriver controls set variable gain and input and output zero. The input attenuator and AC/DC coupling options have front panel controls.
Each amplifier is floating and line powered providing channel to channel isolation. It is fully enclosed in a metal case and mechanically secured when installed in the enclosure. Ten amplifiers mount in a 5 1/4 inch high rack enclosure with a rear mounted connector panel. Mating connectors are supplied with the rack enclosure.