More Intercom Information: On Q/Greyfox Intercoms

On-Q/Legrand is a real innovator in the structured wiring industry. Their products are elegant and relatively easy to install. On our website we have a variety of solutions for everything from communication to computer networking to entertainment. I really do love their intercom system. It is small and powerful. I have their video monitor in my home and can see who is at my front door or what is going on in my swimming pool at the flick of a switch.

On their site On-Q has a glossary of structured wiring terms. If you are considering installing a structured wiring intercom or other product these definitions might help you, so I copied them here for you. If you need more information call us at 1-800-221-8227 and talk to any of our experts. We can help you design a structured wiring system for your home and the service is free. Or if you would rather, take a look at the On-Q solutions on our website.

GLOSSARY

Term	Definition

Off-Hook	when the handset is lifted from it's cradle it is off hook and competes the electrical loop, thus signaling the central office that it wishes to dial tone.
Off-Peak	periods of relatively low system demand. Usually referring to utilities, such as electricity or Internet.
Ohm	the unit of measurement of electrical resistance. The value of resistance though where a potential difference of one volt will maintain a current of one ampere
Ohm's Law	voltage equals current multiplied by resistance. V = c * R c = V / R R = V / c
On-Hook	when the phone handset is resting in its cradle and only the bell is active - it will ring if a call comes in.
Open	a circuit is not complete or the cable / fiber is broken. Sometimes called a fault.
Open Source	projects that are open to the public and which draw on other projects that are freely available to the general public
OSI Model (Open Systems Interconnect Reference Model)	an internally accepted set of standards for communication between different systems from different vendors. The model organizes the communications process into seven categories dependent on their relationship to the user.
	1. Physical Layer
	2. Data Link Layer
	3. Network Layer
	4. Transport Layer
	5. Session Layer
	6. Presentation Layer
	7. Application Layer
Outlet	wall-mounted device for connection to various services such as telephone, data, video, or audio
Over voltage	an increase in voltage similar to a surge but for a longer period of time over 2.5 seconds
Packet	the fundamental unit of information carriage in all modern computer networks
Packet Switching	the process of routing and transferring data by means of addressed packets so that a channel is occupied during the transmission of the packet only, and upon completion of the transmission of the channel is made available for the transfer of other traffic.
Pair	two wires, twisted together with a reciprocal color code.
Pair Twist	the uniform twist of an insulated copper pair that helps to improve the effects of capacitance imbalance and electromagnetic induction.
PAN	Personal Area Network
Parallel Circuit	circuit interconnection where all components share a common positive and common negative connection.
Parental Controls	refers to the ability to restrict access to content based on subject or rating.
Passive	a circuit or device that does not produce gain or use tubes, transistors or integrated circuits.
Passive Subwoofer	a speaker for reproducing bass frequencies that must be power red by a separate power amplifier. Contrasted with "active" or "powered" subwoofers that contain an integral amplifier.
Password	a string of characters that must be entered into a security system in a home or into a computer system to gain access.
Patch Chord	the chords interconnecting terminations at the central distribution panel or between equipment.
Patching	A means of connecting circuits via cords and connectors that can be easily disconnected and reconnected at another point.
Pay-Per-View (PPV)	TV programming services, such as live events or pre-recorded programs that are multicast only to those subscribers that have been authorized by the operator, usually meaning that the subscribers have paid for the right to view the event in advance. In order for the subscriber to place and confirm the order, a communication return-path is required back to the operator.
PBX (Private Branch exchange)	telephone switching center that is owned by a private business, compared to one that is owned by the common carrier or telephone company
Peer To Peer	a simple kind of network that sets up a conversation between two machines without a middleman. Both carry out the same functions.
Peripheral Component Interconnect (PCI)	and internal communications and expansion bus on computers. Most Network Interface Cards are PCI compatible.
Peripheral Device	external computer devices that are attached to the computer though an interface cable, such as CD-ROM drives, modems, and printers.
Personal Computer Memory Card International Association (PCMCIA)	the standard for small, credit card-sized devices, called PC cards. Originally designed for adding memory to portable computers, the PCMCIA standard has been expanded several times and is now suitable for many types of devices.
Photocell	a device that produces an electric current from visible radiant energy (light).
Picture-In-Picture (PIP)	displaying a small picture within a larger picture by scaling down one of the images to make it smaller. Each picture requires a video source (camera, VCR, channel selector). Consumer TV can use POP for viewing two channels at the same time or for viewing taped video and a channel, etc. Videoconferencing uses POP to display pictures from video sources at each participating site on each screen at the same time.
Pixel (Picture Element)	a digital video image is composed of individual dots called pixels that create the image patterns and colors.
Plasma Display	a type of flat-panel display, approximately three to five inches thick, that works by sandwiching a neon/xenon gas mixture between two sealed glass plates with parallel electrodes deposited on their surfaces. The plates are sealed so that the voltage pulse passes between two electrodes, the gas breaks down and products weakly ionized plasma that emits UV radiation. The UV radiation activates color phosphors and visible light is emitted from each pixel.
Plenum	space above the ceiling and below the floor or roof above, used for air distribution or ductwork placement.
Plug	a male component of a plug/ jack connector system in premises wiring that provides the means for a user to connect communications equipment to the communications outlet.
Polarity	describes which side of an electrical circuit is the positive and which is the negative.
Poly Vinyl Chloride (PVC)	the material most commonly used for the insulation and jacketing of cable. Also used to make hard, strong plastic pipe pieces and other products.
PostScript	the page description language created and licensed by Adobe Systems Incorporated. PostScript technology allows various computer software packages to create pages that can be printed on any printer with PostScript Interpreter.
POTS (Plain Old Telephone Service)	The traditional telephone at the end of a telephone line connection to the public switched telephone network
Power Amplifier	electronic device that ingresses the power of an incoming low level signal to accommodate the power requirements of a loudspeaker.
Power Output	a measure of a power amplifier's ability, in watts, to deliver electrical voltage and current to a speaker.
Power Sum
Preamplifier	the control center of an audio/video system. Source component switching is done here, as generally has some degree of signal amplification associated with it.
Premise Wiring System	the entire wiring system on the user's premises, especially the supporting wiring that connects the communications outlets to the network interface jack.
Premises	Telephony term for the space occupied by a customer or authorized/joint user in a building (s) on continuous or contiguous property (except railroad rights of way, etc.) not separated by a public road or highway.
Pre-wire	the installation of wiring in a home before the drywall is installed during new construction.
Private Branch Exchange (PBX)	a small, privately owned version of the phone company's larger central switching office.
Protocol	a set of agreed-upon standards that define the format, order, time, "handshaking" and error checking method for data transfer over a network.
PSTN (public switched telephone network)	the concatenation of the world's public circuit-switched telephone networks, in much the same way that the Internet is the concatenation of the world's public IP-based packet-switched networks
Public Hot Spot	a public location where people can user their laptops, PDAs, or other wireless devices to access the Internet or other network services via Wi-Fi technologies.
Public Switched Telephone Network (PTSN)	the switched telephone network that carries long distance calls and point-to-point network communications.
Pulling Tension	the amount of pull (foot-pounds of tension) placed on a cable during installation.
Punch Block	A type of terminal strip used to connect telephone or data lines to each other. Also called "punch-down block," "quick-connect block," "terminating block" and "connecting block," punch blocks use "insulation displacement connectors" (IDCs), which cut through the insulation as the wire is pushed into them.
Punch Down	a method for securing wire to a quick clip in which the insulated wire is placed in the terminal groove and pushed down with the special tool. As the wire is seated, the terminal displaces the wire insulation to make an electrical connection. The punch down operation may also be called trip the wire as it terminates. Also called cut down. Usually used for telephone wiring.
Quality of Service (QOS)	a networking term that specifies a guaranteed throughput level.
R.E.N.	Ringer Equivalence Number (REN) is the limit set by a Service Provider for the total number of telephones that may be connected simultaneously to a standard wired telephone line.
Radiation	RF energy that is emitted or leaks from a distribution system and travels though space. These signals often cause interference with other communication services.
Radio Frequency (RF)	refers to alternating current having characteristics such that, if the current is input to an antenna, an electromagnetic (EM) field is generated suitable for wireless broadcasting and/or communications. These frequencies cover a significant portion of the electromagnetic radiation spectrum, extending from the nine kilohertz (9 kHz), the lowest allocated wireless communications frequency (it's within the range of human hearing), to thousands of gigahertz (GHz).
	525-1710 kHz	Am Radio Broadcasting
	49 MHz	Unlicensed Devices (typically garage door openers, cordless phones, baby monitors)
	50-54 MHz	Amateur Radio
	54-108 MHz	TV Broadcasting
	154-173 MHz	VHF Industrial / Commercial (Police, Fire, and Ambulance)
	174-216 MHz	TV Broadcasting
	218-219 MHz	Interactive Video and Data
	220-222 MHz	Land Mobile Systems
	310 MHz	Remote Control Products
	450-470 MHz	UHF Industrial / Commercial
	470-806 MHz	UHF TV Broadcasting
	810-890 MHz	Trucking Systems and Cellular Telephone
	902-928 MHz	Unlicensed Devices (Part 15 of the FCC's Rules): 900 MHz used to be designated for utility DA systems, but expired in 1992 and was not reassigned due to under-use.
	928-960 MHz	Multiple Address and Point-to-Point Data Communications; Microwave Frequency band is from 953-959 MHz
	1.8-2 GHz	Personal Communication Services
	2.31-2.36 GHz	Satellite Digital Audio Radio
	2.4-2.483 GHz	Unlicensed Devices
Radio Frequency Interference (RFI)	electromagnetic radiation which is emitted by electrical circuits carrying rapidly changing signals, as a by-product of their normal operation, and which causes unwanted signals (interference or noise) to be induced in other circuits. This interrupts, obstructs, or otherwise degrades or limits the effective performance of those other circuits
Random Access Memory (RAM)	a type of computer memory that can be accessed randomly; that is, any byte of memory can be accessed without touching the preceding bytes. RAM is the primary memory used by a computer for storing short-term data while processing. All data is lost when the power is removed.
Raster	the series of scan lines that make up a TV picture or a computer's display. The term "raster line" is the same as "scan line". All of the scan lines that make up a frame of video form a raster; lines and rows of dots such as those on the illuminated face of a video screen. It is a matrix of pixels or the scan lines on a CRT.
RBOC (Regional Bell operating companies )	the result of the United States antitrust action against AT&T in 1983.
Read Only Memory (ROM)	computer memory where data has been prerecorded. Once data has been written onto a ROM chip, it cannot be removed and can only be read. ROM retains its contents even when the computer is t turned off.
Rear Projector	a type of viewing device with a translucent pane of glass or acrylic with a customized coating and structure to optimally refract video and computer imagery projected onto the side farthest from the audience.
Receiver	component used in home theater and stereo applications. A decoder, audio/ video switcher, AM/FM tuner, and an amplifier built into one unit. The part of a communications system that converts electrical signals into visible or audible form.
Red, Green, Blue (RGB)	the chroma information in a video signal. The basic components of a color television system. They are also the primary colors of light in the additive color process.
Redacted Instruction Set Computer (RISC)	a method of computer processor design where the processor uses several small, simple operations to break down a complex calculation. RISC excels at small instructions.
Redundancy	planning for future needs or problems by running extra cables during the rough-in phase.
Reflector Lamp (R-Lamp)	an incandescent filament or electric discharge lamp where the sides of the outer blown-glass bulb are coated with a reflecting material so as to direct the light. The light-transmitting region may be clear, frosted, or patterned.
Refresh Rate	the rate at which the picture redraws itself in one second. Usually expressed in hertz (Hz).
Regional Bell Operating Company (RBOC)	seven RBOCs exist, each owns two or more Bell Operating Companies (BOCs). The RBOCs were carved out of the old AT&T/Bell System during the divestiture of the Bell operating companies from AT&T in 1984
Registered Jack (RJ)	telephone and data jacks/ applications registered with the FCC.
Remote Alarm	an alarm signal that is transmitted to a remote central monitoring station.
Repeaters	a device that amplifies and regenerates signals so they can travel further.
Residential Gateway (RG)	a devices that allows consumer premise equipment connected to in-home networks to access and use services from any external network regardless of media.
Resistance	the opposition to the current caused by the nature and physical dimension of a conductor. Expressed in ohms.
Resolution	the density of lines or dots for a given area that make up an image. Resolution determines the detail and quality in the image. A measure of the ability of a camera or video system to reproduce detail, or the amount of detail that can be seen in an image. A sharp, clear picture has high resolution.
Return Loss	noise or interference caused by impedance discontinues along the transmission line at various frequencies. Expressed in decibels.
Return Path	the communications connection carrying signaling from the subscriber, back to the operator. A return path is required for true interactive television, and, for on-demand services such as pay-per-view programming, VOD, and games.
RG59 Cable	a coaxial cable used for broadband video applications with a 22 gauge center conductor. Uses standard "F" connectors for video equipment connections.
RG-6	low loss at high frequency for satellite television and cable modem
RG6 Cable	a coaxial cable used for broadband video applications with a 20 gauge center conductor, allowing a higher bandwidth then RG59 cable. Uses standard "F" connectors for video equipment connections.
Ring / Tip	The transmit and receive wires on a telephone.
Ring topology	A network topology in which every node has exactly two branches connected to it. These nodes and branches form a ring. If one of the nodes on the ring fails than the ring is broken and cannot work. A dual ring topology has four branches connected to it, and is more resistant to failures.
RJ	general term for electrical connector designs registered with the US Federal Communications Commission
RJ11	a communications jack with four wire connection most commonly used for telephones, modems and fax machines.
RJ31	a special telephone jack used to allow equipment (typically security systems) to seize immediate control of the phone line even if that phone line was in use.
RJ45	a communications jack were eight wire connection most commonly used to connect computers and other devices to a local area network (LAN). RJ-45 connectors look similar to RJ11 connectors used for connecting telephone equipment but that are somewhat wider.
Rough-In	the phase of a project where the boxes, cables, and in-wall connections are installed, before the drywall is installed.
Router	a device that directs data traffic among different networks. Routers have software that understand a wide number of protocols and can make complex decisions.