Powerpoints Telephone Flashcards
Define following:
Backplane
Main board where other circuits and power supplies are plugged into.
Bandwidth:
Difference in Hz between ↑ and ↓ frequency of a group or band of frequencies (300Hz and 3100Hz)
BPS:
Bits per second
Buffer:
Storage device in a computer system that compensates for a difference in the rate data flows during transmission.
Byte:
8 bits
Bit:
Unit of information in binary (1+0)
CO (Central Office):
Telecom facility where switching of the telephone calls is accomplished.
COS (Class of Service):
Features and outside line accessible to extensions within a PBX system based on the user’s privilege level.
CODEC:
Chip contained within the line unit, converts analog to digital and then uses Pulse Code Modulation (PCM).
Cross Connect:
Connections between two cables on IDF or MDF.
Flash (Hookflash):
Momentary depress and release a hookswitch (i.e. conference,transfer or another call)
Frequency:
Number of cycles completed per units of time measured in Hertz (Hz)
Ground Start:
Signaling that uses DC in a ground return path to request service.
Hertz:
Unit of measurement for frequency (1 Hz = one cycle per second)
Hookswitch:
Physical switch on the telephone base.
Inside Plant:
Within the company or inside customer’s facility.
ISDN (Integrated Services Digital Network)
Simultaneous Tx of voice and data over multiplexed communications circuits.
Interconnect:
Connection between CPE (customer’s primary equipment) and public switched network.
Intermediate Distribution Frame (IDF):
Extension of the MDF (main) and connected by multi-pair copper or fiber optics.
KSU (key service units):
Cabinet that contains the control modules associated with key telephone systems.
Local Exchange:
Switch office where outgoing/incoming calls are routed and directed to end user / end office.
Loop:
“Last mile” communication path between company and subscriber’s site, referring to the two halves of a communication circuit.
Loss:
Reduction of power in a circuit, measured in -dB.
Microwave:
RF between 1 and 20 GHz.
Modem: (modem/demodulator):
Changes digital signals into analog signals for Tx over the telephone lines.
Macmonic: ?
Memory aid that helps you remember something else or an abbreviation for an operation in a computer code.
MUX (multiplayer unit):
Device that contains two or more signals over the same link.
North American Dialing Plan:
Area code, central office code, subscriber number (651-555-1492 example).
Off Hook:
Hookswitch released, closing the tip/ring loop, signaling a request for service.
Outside Plant:
Poles, cables and wires outside the company and customer’s premises.
