encoder: An IC that codes information to be transmitted by either infrared or
radio remote signal. See alsodecoder, integrated curcuit.ESD (electrostatic discharge): Seestatic electricity.farad: The unit of measurement for capacitance. (A microfarad is one mil-
lionth of a farad.) See alsocapacitor.flathead:A type of screw with a flat head and single slot; the screwdriver
used with a flathead screw.flux:A waxy substance used to make molten solder flow around components
and wire, assuring a good joint.frequency: A way to measure how often an AC signal repeats. The symbol for
frequency is f.gain: The amount that a signal is amplified. To calculate this, divide the volt-
age of the signal coming out by the voltage of the incoming signal.gauge: Seewire gauge.ground: A connection in a circuit used as a reference for 0 (zero) volts.H-bridge:A circuit or IC used to control the power to DC motors. See also
intergrated circuit.heat sink: A piece of metal used to protect components. The sink is attached
to the component and draws off heat to prevent destroying the component.hertz (Hz):The measurement used for the number of cycles per second that
occur in alternating current.high pass filter:A circuit that allows signals above a certain frequency to
pass through. See alsolow pass filter.high signal:In digital electronics, a signal at a value of higher than 0
(zero) volts.I:The symbol used for current.IC:Seeintegrated circuit.impedence: In an electrical current, a measurement of opposition to the flow
of alternating current.384 Electronics Projects For Dummies
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