This coupler accepts almost any resistive bridge transducer. It provides for 5, 7.5, or 10-volt excitation.
Coupling may be DC or 1.0 Hz AC. Five sensitivity ranges (plus two board-selectable preamp gain settings) and an off-calibrate vernier sensitivity control afford the user a wide latitude of control.
A major feature of this unit is the auto-balance control. A simple press of the auto-balance switch brings any transducer into zero balance with 20-mV accuracy. Transducer offset errors and weight or tension pre-loads such as encountered in startle, tremor, and ergometric activity or muscle preparations can be instantly zeroed out. The unit may be re-balanced to zero at any time via the manual switch or from program control via the logic input on the rear panel. When the balance switch is pressed the unit goes through an automatic balancing procedure and displays a yellow light indicating it is balanced to within 20 millivolts of zero.
The unit also allows manual balancing. Place the balance switch in the
Manual Balance
position and adjust the balance control knob as necessary. This feature allows for closer tolerances for applications that require more precision.
The resistive bridge coupler is used for applications involving blood pressure, aneroid pressure for respiration and other measures, strain, displacement, and acceleration.
The coupler is designed to couple resistive bridge-type transducers from various manufacturers with excitation voltages of 5, 7.5, or 10 volts into the CI system. It accepts a variety of Coulbourn Instruments and other transducers. A three-position switch permits user selection of the bridge excitation voltage.
Five calibrated sensitivity ranges are selectable and an off-calibrate vernier control permits settings between calibrated points if needed.
Some of the transducers may be excited by two or even three of the excitation voltages extending the gain/sensitivity options. Each transducer's sensitivity is listed on pages 35 and 36 for usable excitation and sensitivity settings.
An AC/DC coupling switch permits decoupling baseline and/or transducer drift via a 1.0 Hz low cutoff filter when desired.
There is an integrated output in addition to the other outputs. This is a convenience when a small amount of "smoothing" of the signal is needed in applications like startle using our ergometric startle platforms. The unit is shipped with a 10-millisecond integrating time constant but this can be changed by the user. Just change the resistor in the push-in sockets behind the integrated output on the board.
