20-428 Owner’s Manual
Page 10 of 50
LTR mode
You can set your scanner so it decodes the talk group IDs used with LTR (E.F. Johnson) systems.
This setting is called the LTR mode.
LTR frequencies are organized in a specific order. Each frequency is assigned a Home Repeater
Number (HR). For the scanner to correctly switch to an active frequency, you must program the
frequencies in HR order, starting with Memory X01 in the selected bank.
Your PRO-2055 scanner features a new tool to help you determine the correct channel mapping for
LTR system frequencies. The scanner’s LTR Repeater Finder displays the current Home Repeater
when monitoring LTR transmissions in manual mode.
To determine the correct Home Repeater programming, enter the system channels of an LTR system
in any order. Be sure to program the mode for each LTR channel to LT. Listen to each channel one at
a time in manual mode and watch for the decoded LTR data at the bottom of the scanner’s display.
When an LTR transmission occurs, you should see the LTR talkgroup information on the bottom
line of the display, and a number preceded by “R” in the bottom right hand corner (i.e., R12). The “R”
number is the Home Repeater number that the current transmission is occurring on. To correctly
program this Home Repeater number into your scanner, be sure that the channel number in the
bank is equal to the number that is displayed after the “R”. For example, if you see R12 displayed on
a particular LTR frequency, that frequency needs to be programmed into Channel 12 of the current
bank in order to track the LTR system activity properly.
LTR systems are trunking systems used primarily by business or private communications service
providers, such as taxicabs, delivery trucks, and repair services. These systems encode all trunking
information as digital subaudible data that accompanies each transmission. Users on an LTR
system are assigned to specific talk groups, which are identified by the radio as six-digit numbers.
These numbers are in the form AHHUUU, where:
A=Area code (0 or 1)
H=Home repeater (01 through 20)
U=User ID (000 through 254)
When the scanner receives a transmission on a channel set to the LTR mode, it first decodes the
LTR data included with the transmission. In the open mode, the scanner stops on the transmission
and displays the talk group ID on the bottom line of the display. In the closed mode, the scanner
only stops on the transmission if the LTR data matches a talk group ID that you have stored in the
bank’s talk group ID list and have not locked out.
LTR systems are frequently programmed so that each radio has a unique ID code.
open and closed modes