Glossary - ADInstruments POWERLAB TEACHING SERIES Owner's Manual

Glossary

AC coupling. A filter option. When AC coupling is chosen, a 0.1 Hz highpass filter before the
first amplification stage removes DC and frequency components below 0.1 Hz. This removes
slowly changing baselines.
ADC (analog-to-digital converter). A device that converts analog information into some cor-
responding digital voltage or current.
amplitude. The maximum vertical distance of a periodic wave from the zero or mean position
about which the wave oscillates.
analog. Varying smoothly and continuously over a range. An analog signal varies continuously
over time, rather than changing in discrete steps.
analog input. This refers to the connectors on the front of the PowerLab marked 'Input'. These
inputs are designed to accept up to ±10 volts. Inputs can be either single-sided or differential
(the latter only in the case of the pod connectors).
analog output. This refers to the connectors on the front of the PowerLab marked 'Output'.
The analog output provides a software-controlled variable output (±10 V) that can be used
with applications either directly as a stimulator, or to control peripheral devices. Not for use
with human subjects.
analysis. When the PowerLab is not physically connected to the computer, then ADInstru-
ments software can be used to analyze and manipulate existing files if the analysis option is
chosen.
Applied Part. A part which necessarily comes into physical contact with the subject during
normal use
BNC (bayonet nut connector). A type of cable or connector; a BNC-to-BNC cable connects two
BNC connectors.
bridge transducer. A type of transducer using a Wheatstone bridge circuit. In its basic form,
the bridge consists of four two-terminal elements (usually strain gauges) connected to form a
quadrilateral. An excitation source is connected across one diagonal, and the transducer out-
put is taken across the other.
51 PowerLab Teaching Series - Owner's Guide