TMC Radio SRP 9100, Service Manual

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2 ~ SERVICE PHILOSOPHY
Link Establish Time
A delay incorporated into the start of every selective call or DTMF transmission
that allows for the finite delay of the radio equipment in responding to any radio
signal. This includes both the commencement time of the originating transmitter
and the response time of the receiver.
Locked
A state of a channel whereby it is not possible to change channels using the
normal up/down keys on the channel menu until the OK key is pressed. See Auto
Channel Selection Lock.
MEP Miniaturisation Extent Parameter. Used in systems that use ANN numbering.
Modifier
Part of a dialled string that modifies the nature of the call made to a number (e.g.
dialling "*9" before the number that is to be dialled will modify the call to be an
emergency call).
MPT1327 A signalling standard for Trunked Private Land Mobile Radio Systems. Defined for
systems in the UK but also used outside the UK. Issued January 1988.
MPT1343 A System Interface Specification for commercial Trunking networks. Defined for
systems in the UK but also used outside the UK. Issued January 1988.
Noise Blanker
A circuit designed to reduce automotive ignition interference.
NDD Network Dependent Data. This is a field within the CCSC codeword that is used by
the trunking system to identify information about the trunking network and, in
particular, information specific to the site that is radiating the control channel. It is
used by the radio when it is acquiring a control channel to identify valid channels.
Null Id A Selcall identity that is not defined and whose tones' field is displayed as a blank.
Open A state where transmit and receive are allowed. The channel is no longer open
when reset. Contrast with Closed.
Normally an Open channel would not have Selcall Mute and PTT Inhibit would be
disabled.
OPID Network Operator Identity used in Regional Systems. See Roaming.
PABX Private Automatic Branch Exchange.
Password
An optional password system available on the radio. This feature is only available
if the radio does has a display and a keypad. To make available: go to Hardware
Components, Terminal Settings and set Product Type to one which has a display
and a keypad.
PFIX
The 7 most significant bits of an MPT1327 address number. Normally same fleet
units have same prefix. Relates to individual and group address numbers.
PLL Phased Locked Loop.
PMR
Private Mobile Radio (not normally trunked).
Priority Channel A channel in a search group that is scanned between every other channel.
PSTN Public Switched Telephone Network
PTT Press To Talk. This is the term given to the operator’s key normally used to
commence transmitting a message.
PTT Inhibit A state whereby transmission using the PTT is not allowed. Also know as Tx
Lockout.
PWM
Pulse Width Modulation
Queuing The storing of a Selcall Identity for later transmission.