Functional Block Diagram - Blonder Tongue Laboratories Inc.

Broadband Specification Guide
CATV Terms & Definitions
Termination
Resistive device at end of distribution line or unused outputs of equipment
to avoid reflections (ghost).
Thru-Line Loss
Insertion loss of a tapoff.
Tilt Control
Circuit on an amplifier to compensate for cable slope. Also referred to as
slope control.
Transmitter
In a fiber optic system, the device which converts a modulated
electrical signal into an optical signal for transmission through a fiber. A
transmitter typically consists of a light source (LED or diode laser) and
driving electronics.
Transponder
A frequency converter (translator) aboard a satellite that changes the
uplink signal to the downlink signal and provides amplifications. Typical
C-Band domestic satellites have 24 transponders.
Trap
A device used to attenuate specific frequencies of channels.
Triple Beat Distortion
Spurious signals generated when three or more carriers are passed
through a nonlinear circuit. The spurious signals are sum and difference
products of any three carriers, sometimes referred to as "beats." Triple
beat distortion is calculated as a voltage addition.
Trunk
1. One telephone communication channel between (a) two ranks of
switching equipment in the same central office, (b) between central
office units in the same switching center, or (c) between two switching
centers. A trunk is for the common use of all calls of one class between
its two terminals.
2. A sub-system within a trunk plus feeder designed CATV system which
provides somewhat limited, arterial distribution of signals broadly
across the CATV service area.
Trunk Plus Feeder Design (trunk/feeder)
A technique for designing CATV systems which involves two or more
transmission levels, applied within different sub-systems of the same
system. Generally requires some significant amount of paralleling
cable placement.
TVRO
An abbreviation for "television receive only." Defines a facility which can
include antennas, preamplifiers, and receivers for the reception only of
television signals from a geostationary satellite in space.
Twinlead
A balanced transmission line usually of 300 ohm impedance.
Two-way
Describing a transmission system, which can transport signals in both
directions simultaneously.
Two-way Filter
A combination of low and high pass filters to subdivide spectrum in a
CATV system, allocating some spectrum for transmission in one direction,
and some spectrum for transmission in the opposite direction.
T-1 Carrier System
A 24-channel, transistorized, time-division, pulse-code modulation, voice
carrier used on exchange cable to provide short-haul trunks. Uses two
pairs, in one or two cables, for two directions of transmission. Requires
regenerative pulse repeaters at 6000 feet intervals.
UHF
Ultra High Frequencies TV channels 14-69 (470-806 MHz)
Ultra-high Frequency (UHF)
The radio spectrum between 300 and 3,000 MHz. The term UHF is also
commonly used to denote standard television channels 14 through 69,
which fall within this spectrum.
Ultraviolet
Electromagnetic radiation with wavelengths between about 40 and 400
nanometers. Radiation between 40 and 200 nm is termed "vacuum
ultraviolet" because it is absorbed by air and travels only through a
vacuum. The "near" ultraviolet has wavelengths close to those of visible
light; the "far" ultraviolet has shorter wavelengths.
Underground Cable
Cable installed in subsurface conduits terminating at intervals in manholes,
thus permitting the placing, replacing, or removal of cables at will.
Uplink
Transmission from earth to a satellite.
Usable Gain (See Gain, usable)
VHF
Very High Frequencies TV channels 2 thru 13 and FM (54-216 MHz).
Velocity of Light
The velocity of light in a vacuum is 2,997,925. meters per second or
186,280 miles per second. For rough calculations the figure of 3,000,000
meters per second is generally used.
Very High Frequency (VHF)
The radio spectrum between 30 and 300 MHz. The term VHF is also
commonly used to denote standard television channels 2 through 13,
which fall within this spectrum.
Vestigial Side Band (VSB)
In amplitude-modulated transmissions, a portion of only one sideband
of a modulated carrier. The modulated carrier is passed through a filter
having a graduated cut-off characteristic near the carrier frequency. A
substantial portion of the modulated carrier is suppressed in this fashion.
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