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Database:
All of the information stored in a computer available
for retrieval and updating.
dBm:
A measurement of the power of a signal received
above a reference power of 1 milliwatt (10
-3
watts).
dBrn:
(dB reference noise): The reference for noise
measurement, a level equivalent to a tone at –90
dBm. 0 dBrn = –90 dBm and 0 dBm = 90 dBrn.
dBrnC:
dBrn measured with C-message weighting.
Decibel (dB):
A unit for measuring the relative strength of a signal
parameter, such as power or voltage, often used in
measuring loss or gain of power in a device or circuit.
DLL:
Dial Long Line – a loop treatment device to boost the
loop current.
Dial Pulse:
The method of telephone dialing by alternately
opening and closing (pulsing) a contact in the
telephone (dialing the digit 7 produces seven pulses).
Dial Up:
The means of establishing a connection through the
network over public dial ports.
Digital:
Information or graphic data that has been translated
into a discrete numerical value, and therefore can be
manipulated and reproduced without loss of quality.
DTMF:
Dual Tone Multiple Frequency – a touch-tone dial
frequency.
