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14 result(s) found where the letter starting with "A"

Acceleration , 2g tip-over
The ability of the oscillator to maintain its frequency as it changes orientation with respect to gravity
 

Accuracy
The degree of conformity of a measured or calculated value to its definition or with respect to a standard reference (see uncertainty).
 

Adjustment range
See mechanical frequency adjustment or voltage frequency adjustment
 

Ageing
The systematic change in frequency over time because of internal changes in the oscillator. For example, a 100 kHz quartz oscillator may age until its frequency becomes 100.01 kHz (see drift). Ageing is the frequency change with time when factors external to the oscillator such as environment and power supply are kept constant. See also "frequency Ageing"
 

Allan Deviation
A measure of the short term frequency stability of the oscillator made in the time domain. It is calculated and presented as the value of frequency variance over a specified time period (square of the standard deviation). It is a useful measurement for industries where accurate time intervals are required (e.g. global positioning, measurement of relativistic effects, etc.) see also Allen Variance.
 

Allan Variance
The standard method of characterizing the frequency stability of oscillators in the time domain, both short and long term, established by Dr. Allan
 

AM
Amplitude Modulated
 

Ambiguity
The properties of something that allows it to have more than one possible meaning. In the case of a clock, it displays 3 hours and 5 minutes, it could be morning or night. The clock is then said to be ambiguous to the hour.
 

ANSI
American National Standards Institute
 

ASCII
American Standard Code for Information Interchange
 

ATM
Asynchronous Transfer Mode (e.g. ATM switching)
 

Atomic Time Scale (TA)
A time scale based on atomic or molecular resonance phenomena. Elapsed time is measured by counting cycles of a frequency locked to an atomic or molecular transition. Earlier time scales were based on the rotational rate of the earth.
 

AU
administrative unit; a managed entity within the SDH structure
 

AV
Analog Video