Tait TB7100, Инструкция по установке и эксплуатации

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TB7100 Installation and Operation Manual Glossary 133
© Tait Electronics Limited December 2005
F
FFSK
FFSK (fast frequency shift keying). In Trunking applications this is the
method by which code words are sent over the control channel. In 1200
baud FFSK, a 1200 Hz tone represents a zero and an 1800 Hz tone
represents a one.
frequency band
The range of frequencies that the equipment is capable of operating on.
front panel
The part of the chassis that has the user interface on it.
Full Duplex
Full duplex is the action of receiving and transmitting at the same time.
function key
A function key is a key on a radio or radio accessory that can have functions
assigned to it.
G
gating
Gating is the process of opening and closing the receiver audio path. When
a valid signal is received, the receiver audio path opens.
GPIO
General Purpose Input Output (GPIO) lines are used on the TB7100 to
configure it for different modes.
H
hysteresis
Hysteresis is the difference between the upper and lower trigger points. For
example, the receiver gate opens when the upper trigger point is reached,
but will not close until the level falls to the lower trigger point. An adequate
hysteresis prevents the receiver gate from repeatedly opening and closing
when the level is about that of the trigger point.
I
inactive
Digital outputs are inactive if the base station is doing nothing to them. They
are floating, open collector outputs. Digital inputs are inactive when they are
open circuit.
indicator
Indicators provide feedback to the radio user on how the current operation
is proceeding and on the operating state of the radio. For example, keypress
confidence tones are the tones heard when a keypad key or a function key
is pressed and tell the user that an action is permitted. Tait radios use
combinations of audible indicators and visual indicators.
inhibit
Prevents the radio state changing.