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GLOSSARY
DTMF
Dual Tone Multifrequency.
Electret Microphone
A microphone made up of a capacitor with a dielectric that holds a permanent
electric charge.
FET
Field Effect Transistor.
Hook Switch
A switch inside the telephone which closes when the receiver is lifted.
IC
Integrated Circuit.
FCC
Federal Communications Commission.
Local Loop
The pair of wires between a telephone set and the telephone company Central
Office.
Mark Interval
The portion of a dial pulse during which loop current is flowing.
Pulse Dialing
A dialing system in which the number of pulses on the local loop represents the
number dialed.
Ring Wire
The red (negative) wire of the local loop.
Sidetone
The sound heard from the telephone receiver due to the speaker’s own voice.
Space Interval
The portion of the dial pulse during which current is not flowing.
Tip Wire
The green (positive) wire of the local loop.
Tone Dialing
A dialing system in which a combination of two frequencies on the local loop
represent the number dialed.
USOC
Universal Service Order Code.
Zener Diode
A diode that has nearly constant voltage drop over a wide range of reverse current.
Answer
s to Quiz:
1.B;
2.B;
3.C;
4.C;
5.A;
6.D;
7.C;
8.B;
9.A;
10.B
Содержание AK-700
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