Interval between two sounds whose fundamental
frequencies differ by a ratio of 2 to 1. 440 Hz. is one
octave above 220 Hz.
offset null
An op amp control pin used to eliminate the effects of
internal component voltages on the output of the device.
ohm
Unit of resistance symbolized by the Greek capital
letter omega (W).
ohmmeter
Device used to measure electrical resistance.
Ohm's law
Relationship between voltage, current and resistance.
Ohm's law states that current in a resistance varies in
direct proportion to voltage applied and inversely
proportional to resistance.
Ohms per volt
Refers to a value of ohms per volt of full scale
defection for a moving coil meter movement. The number
of ohms per volt is the reciprocal of the amount of
current required to produce full scale deflection of the
needle. A meter requiring 50 microamps for full scale
deflection has an internal resistance of 20 kW
per volt. The higher the ohms per volt rating, the more
sensitive the meter.
one-shot
Monostable multivibrator.
op-amp
Abbreviation for operational amplifier.
open loop gain
Gain of an amplifier when no feedback is present.
open loop mode
An amplifier circuit having no means of comparing the
output with the input. (No feedback.)
operational amplifier
A high gain DC amplifier that has a high input impedance
and a low output impedance. Op-amps are the most basic
type of linear integrated circuits.
oscillate
To produce a continuous output waveform without an input
signal present.
oscillator
An electronic circuit that produces a continuous output
waveform with only DC applied.
oscilloscope
An instrument used to display a signal graphically.
Shows signal amplitude, period and waveshape in addition
to any DC voltage present. A multiple trace oscilloscope
can show two or more waveforms at the same time for
phase comparison and timing measurements.
out of phase
When the maximum and minimum points of two or more
waveshpes do not occur at the same time.
output
Terminal at which a component, circuit or piece of
equipment delivers current, voltage or power.
output impedance
Impedance measured across the output terminals of a
device without a load connected.
output power
Amount of power a component, circuit or system can
deliver to a load.
overload
Codition that occurs when the load is greater than the
system was designed to handle. (Load resistance too
small, load current too high.) Overload results in
waveform distortion and/or overheating.
overload protection
Protective device such as a fuse or circuit breaker that
outomatically disconnects a load when current exceeds a
predetermined value.