The Model 4290 Accelerometer/Data Amplifier is a dual-channel, medium gain device. Each channel can be configured as an AC-coupled amplifier with constant-current excitation for sensors, or as a differential input AC or DC amplifier. Designed for use in the instrumentation systems test environment, it includes many features that simplify the test setup of accelerometers and other sensors requiring differential input signal processing.
In order to simplify the setup of a large number of channels, the 4290 contains both Zero and Calibrate signal relays, which can be controlled from either the front panel or remotely via the RS-232 serial link. When actuated, the Zero relays provide the user with the ability to short the input of any amplifier to determine a base line noise for the amplifier. This is a simple way to deduce the amount of noise contributed by the sensor prior to amplification. A quick check of gain settings and accuracy can be made by activating the Calibrate signal relay that applies one of three internal DC reference signal levels (1V, 100 mV, 40 mV) or a user-supplied AC or DC signal to the input of a selected channel. These two features allow the user to quickly troubleshoot large channel-count systems.
Reduced High Frequency Noise
The 4290 provides a full 100 kHz bandwidth at a gain of 200. High frequency noise is significantly reduced using a 4 pole low pass filter with programmable cutoffs at 1, 5, or 20 kHz. A bypass mode in this filter allows the user to utilize the full 100 kHz bandwidth if desired.