User's Manual

VTU-3 Users Guide
Page 18 of 18
LoJack Confidential Proprietary
Document Not To Be Copied Or Retransmitted In Any Form Without Prior Authorization
Standard Message A message generally sent from the TRTU system to the VLUX unit.
Standard messages conform to the original LoJack message format
Timed Remote Transmitter Unit (TRTU).......... Refers to a system of synchronous RTUs which incorporate
precise timing control, facilitating the use of time-windowed synchronization of VLU-
5Ns. The LoJack TRTU system and the TRTU systems use different timing.
TRACKER Network Unit (TNU) A name for a TRACKER version of a VLU-5N.
TRACKER Repeater Unit (TRU)...A specially configured TRACKER "MK 2" unit that relays TRTU messages
downstream and Uplink messages upstream. TRUs can be daisy chained such that a
TRU feeds another TRU. Used to fill in areas of coverage and relay reply codes from
activated units.
Transmitter Battery A 6V battery that provides power solely to the transmitter circuits in a
portable VLU-5N. This battery uses the same input connection as the Backup Battery
on the Adaptive Model.
Transmission System Communications subsystem that interfaces to Remote Transmission Units
Transponder Category of RF equipment that the Vehicle Locating Unit belongs in.
Unit ID
Uplink Frequency Shift Keying transmission from Vehicle Locating Unit to Remote Transmission
Units
Uplink An infrastructure enhancement that allows VLUs to send appropriately formatted
messages directly to the TRTU system. The Uplink operates on the same basic
frequency as the rest of the system infrastructure. The Uplink channel uses a much
slower data rate to help make up for the reduced signal margin of the VLU transmit
power relative to that of TRTU towers.
Uplink Central.....
Uplink Receiver... Receiver Analogue Unit designed for decoding Uplink (Frequency Shift Keying)
messages transmitted by Vehicle Locating Unit s
VB VOICE VB VOICE is a Visual Basic programming module, including a hardware board, which
performs automated calling of phone numbers with voice messages.
Vehicle Transceiver (VT, VLU, or VLC).A vehicle mounted module, which can be activated by a compatible
system and tracked by a tracking receiver. Also referred to as Vehicle Location Units
(VLUs), or Vehicle Location Communicators (VLCs).
Vehicle power The +12V vehicle electrical system supplies power to the VLU-5N in either TRTU or non-
TRTU configurations, except in portable units.
Vehicle Tracking Receiver or Units (VTR or PTC) ....Provides the ability to track an activated VLU-5N, and
allows the vehicle location to be determined. Usually mounted on police vehicles and
are often referred to as Police Tracking Computers (PTCs).
VLU Vehicle Locating Unit. A transponder hidden in the vehicles that can be remotely
activated. The transmission from Vehicle Locating Unit can be decoded by Vehicle
Tracking Unit.
VTU Vehicle Tracking Unit. A direction-finding receiver used by the tracking agency in a
mobile environment. (Used to be called PTC.)