Functional Block Diagram - Blonder Tongue Laboratories Inc.

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Broadband Specification Guide CATV Terms & Definitions Infrared Electromagnetic radiation with wavelength between 0.7 micrometer and about I millimeter. Wavelengths at the shorter end of this range are frequently called "near" infrared, and those longer than about 20 micrometers, "far" infrared. Intrinsic Noise (See Noise, intrinsic) Isolation Electrical separation (or loss) between two locations or pieces of equipment. Degree of isolation usually specified in dB. Jacket A layer of material, generally plastic, that surrounds an optical fiber to protect it from physical damage. Unlike the cladding, the jacket is physically distinct from the fiber core. Joule An international unit of work or energy. The work required to maintain a current of one ampere through one ohm for one second. A Watt-second. Kilo A prefix for one thousand (1,000 or 101). Kilobit One thousand bits. Kilocycle (Kc) See Kilohertz. Kilohertz (kHz) 1. One thousand hertz. 2. One thousand cycles per second. Ku Band Range of frequencies used in satellite transmissions. Common uplink frequency for U.S. domestic satellites is 14 to 14.5 GHz with a downlink frequency of 11.7 to 12.2 GHz. Laser Acronym for "light amplification by stimulated emission of radiation." A device which generates or amplifies electromagnetic oscillations at wavelengths between the far infrared (sub-millimeter) and ultraviolet. Like any electromagnetic oscillator, a laser oscillator consists of two basic elements: an amplifying (active) medium and a regeneration or feedback device (resonant cavity). A laser's amplifying medium can be a gas, semiconductor, dye solution, etc. Feedback is typically from two mirrors. Distinctive properties of the electromagnetic oscillations produced include monochromaticity, high intensity, small beam divergence, and phase coherence. As a description of a device, "laser" refers to the active medium plus all equipment necessary to produce the effect called lasing. Lashed Cable An aerial cable fastened to its supporting messenger by a continuous spirally wrapped steel wire. Light Emitting Diode (LED) Acronym for light emitting diode. Lightguide Synonym for optical waveguide. Light Source A generic term that includes lasers and LED's. Lightwave Any electromagnetic radiation having a wavelength in the Range from 800 to 1,600 nanometers in the near infrared region. Linear The characteristic of a device or network whose output signal voltage is directly proportional to its input signal voltage. Line Extender An unsophisticated amplifier operating at relatively high transmission levels in the feeder sub-system of a trunk plus feeder designed CATV system. LNA Low Noise Amplifier. Provides initial amplification of downlink signal at antenna location. LNB Low Noise <strong>Block</strong> (converter). Integrated LNA and down converter. Available in either C or Ku band inputs. The most prevalent output frequency scheme is 950-1450 MHz, however other schemes that have been used include 900-1400, 1000-1500 and 270-770 MHz. Local Origination Channels that are generated on site, such as those that are derived from character generators, laser disks, or VCR’s in the headend. Long Wavelength As applied to fiber optic systems, this term generally refers to operation at wavelengths in the range of 1,100 nanometers to 1,700 nanometers. Look Angle TVRO term that refers to both the azimuth and elevation angles required to sight or aim a dish to a given satellite. Loss Reduction in signal strength usually expressed in dB. Synonymous with attenuation. Low Band The radio spectrum between 54 and 88 MHz. Standard VHF television channels 2 through 6 fall within this spectrum. 88
Broadband Specification Guide CATV Terms & Definitions Loss Power dissipated in a device, cable, or network expressed in decibels. See attenuation. Matching Obtaining like impedances to provide a reflection free transfer of signal. Matching Transformer Device to transform signals from one impedance to another impedance. IN TV systems usually 75 ohm unbalanced to 300 ohm balanced. Also known as a balun. MATV Master Antenna Television. MDF Short for main distribution frame, a cable rack that interconnects and manages the telecommunications wiring between itself and any number of IDFs. Unlike an IDF, which connects internal lines to the MDF, the MDF connects private or public lines coming into a building with the internal network. For example, an enterprise that encompasses a building with several floors may have one centralized MDF on the first floor and one IDF on each of the floors that is connected to the MDF. MDS Is an acronym for Multipoint Distribution System. MDS is former line-of-sight microwave transmission consisting of two 6 MHz analog channels in the 2150-2162 MHz frequency range. It was typically used to provide premium programming on a subscription basis. The FCC has subsequently relocated this service to the BRS/EBS band. The 2150-2162 MHz band is now allocated for Advanced Wireless Services (AWS). Mechanical Splice A fiber splice accomplished by fixtures or materials, rather than by thermal fusion. Index matching material may be applied between the two fiber ends. Media Retrieval Type of headend system used in educational facilities that allows remote control of headend video playback equipment (VCR’s, laser disks, etc.) from the classrooms. Mega- A prefix for one million (1,000,000 or 101). Megabit (mb) One million bits. Megacycle (mc) (See Megahertz) Megahertz (MHz) One million hertz. One million cycles per second. See Hertz and Cycle. Micro- A prefix for one millionth (10-'). Micron The unit used for specifying the wavelength of light, equal to one millionth of a meter. Microwave A term denoting radio waves which are in the electromagnetic spectrum at frequencies approximately 1,000 MHz and higher. Mid-band The radio spectrum between 88 and 174 MHz, which lies between standard VHF television, channels 6 and 7. CATV channels A through I (nine channels) fall within the mid-band spectrum. Mid-Split Two way cable communications frequency plan, where the diplex filter’s crossover frequency is in the mid-band. Consists of an incoming frequency range of 5-108 MHz and an out-going of 150-450 MHz. Milli- A prefix for one thousandth (10-1). Milliwatt One thousandth of a Watt. Mixer Device to combine signals while maintaining impedance. MMDS Abbreviation for Multichannel Multipoint Distribution Service, also known as Wireless Cable. Over-the-air subscription service transmitted on MDS and ITFS frequencies now known as the BRS/EBS band. Mode Field Diameter A functional representation of the energy carrying region of the fiber. Also referred to as Spot size. Modem A single unit of equipment which combines the functions of modulator and demodulator. This is an economical arrangement, since the two circuits can use common elements. Modulation MER is a measure used to quantify the performance of a digital RF transmitter or receiver in a communications system using digital modulation such as QAM or QPSK. It is caused by various system imperfections such as noise, low image rejection ratio, phase noise, carrier suppression, distortion, etc. Modulation Error Rate (MER) The process by which some characteristic of a wave such as amplitude, frequency, or phase is varied in accordance with a modulating wave. This term is also commonly used to refer to the information (intelligence) present on a modulated carrier. 89
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Functional Block Diagram - Blonder Tongue Laboratories Inc.

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