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21 result(s) found where the letter starting with "D"

Date
A unique instant defined in a specified time scale. NOTE: The date can be conventionally expressed in years, months, days, hours, minutes, seconds, and fractions. Also, Julian Date (JD) and Modified Julian Date (MJD) are useful dating measures (see Julian Date and Modified Julian Date)
 

dB (decibel)
A measure of relative amplitude of a sine wave
 

dBm
dBm Decibels referenced to 1 milliwatt, it must be specified with load impedance (usually 50 ohms)
 

DCC
data communications channel; the main management channel inside SDH
 

DCLS
Direct Current Level Shifted
 

DCS
digital cross-connect system; an electronic multiport switch for digital traffic
 

DDS
Direct Digital Synthesiser

 

Design Frequency
See nominal frequency
 

Deviation Linearity
See linearity
 

Deviation slope polarity
The slope of the change in frequency with respect to the control voltage. A positive polarity indicates the frequency increases when the control voltage becomes more positive
 

DGPS
Differential Global Positioning System
 

DHCP
Dynamic Host Configuration Protocol
 

Direct compensation
A technique of building crystal oscillators in which the circuit components affecting the crystal load reactance are selected to have temperature characteristics such, that the crystal is re-tuned over temperature to reduce the effects of temperature on the frequency of the oscillator
 

DLC
Digital Loop Carrier
 

DO - (Disciplined Oscillator)
An oscillator with a servo loop that has its phase and frequency locked to an external reference signal
 

DOCXO
Double Oven Controlled Crystal Oscillator. A crystal oscillator maintained, during operation, at a fixed temperature so that frequency changes due to ambient temperature changes do not affect its performance.
 

Drift
A measure, in hertz per second, of how quickly the skew of a clock is changing. See also "skew"
 

Drift (frequency)
The linear (first-order) component of a systematic change in frequency of an oscillator over time. Drift is due to aging plus changes in the environment and other factors external to the oscillator (see aging)
 

DTCXO
Digital Temperature Compensated Crystal Oscillator
 

DUT1
The approximate time difference between UT1 and UTC, expressed to the nearest 0.1 s. DUT1 = UT1 + or - UTC. DUT1 may be regarded as a correction to be added to UTC to obtain a better approximation to UT1. The values of DUT1 are given by the International Earth Rotation Service (IERS) in integral multiples of 0.1 s
 

Duty cycle
A term with identical meaning to symmetry. Use of the term "symmetry" is preferred to avoid confusion with other parameters. See symmetry