User's Manual

CONVENTIONAL MODE FEATURES
35
F2 key to begin the data transfer. This mode over-
writes all this information currently in the slave
radio. None of the previous information is retained
except for the IDs as described in Section 5.16.1.
5.17 PROJECT 25 MODE FEATURES
NOTE: The following features are unique to
conventional P25 channels.
5.17.1 UNIT ID CODE
Each radio that operates on Project 25 (digital)
channels is programmed with an eight-digit unit ID.
This ID is unique for each radio and can be any
number from 1-16,777,216. When power is turned on
with a Project 25 channel selected, this ID is briefly
displayed.
5.17.2 GROUP ID CODE
Each Project 25 channel is programmed with a
group ID that determines which group of radios will
receive the call. A call is received on a channel if a
selected or scanned channel is programmed with that
ID and the correct NAC is detected (see following).
Group IDs can be any number from 0-65,535. Group
ID detect can be disabled by the Normal/Selective
squelch function described in Section 5.5.2 or the
monitor mode described in Section 5.3
5.17.3 NETWORK ACCESS CODE
Project 25 conventional channels also use a NAC
(Network Access Code) to control which calls are
received on a channel. The NAC can be 0-4095, and
each transmit and receive channel can be programmed
for a different code. Other operation, such as moni-
toring before transmitting, is similar to that of analog
channels. NAC (and group ID) detect can be disabled
by the monitor mode described in Section 5.3.
5.17.4 P25 GROUP CALLS
P25 group calls are placed by simply selecting the
channel programmed for the desired group, monitoring
the channel if required, and transmitting.
When a P25 group call is received, the alias (or
frequency) of the selected channel is displayed. The
radio can be programmed so that the following are
also displayed for 0.5-7.0 seconds or continuously
during the call.
P25 PTT ID- The unit ID of the radio placing the
call is displayed.
P25 Talk Group - The alias of the talk group on
which the call is being received is displayed.
User Group ID - If the group ID of the call being
received is included in a preprogrammed User
Group ID list, the alias programmed in that list for
that group is displayed.
Changing a Channel Talk Group
If the Digital Talk Group Select option switch or
Select TG menu parameter is programmed, the talk
group assigned to a channel can be changed by the
user. The new talk group continues to be assigned to
the channel until it is manually changed again (cycling
radio power or selecting another channel does not
reselect a default talk group). Change the talk group
assigned to a channel as follows:
1. Select the channel to be changed.
2. To select the talk group from the list of programmed
talk groups, briefly press the Talk Group Select
option switch or select the Select TG > ID List
menu parameter. Then press the Up/Down switch
until the alias of the desired talk group is displayed.
If talk group selection has been disabled on the
channel by programming, “NO LIST” is displayed,
a tone sounds, and no change occurs. Press the F2
switch to select the talk group and return to normal
operation.
3. To enter a new talk group number from 1-65,535,
press and hold the Talk Group Select option switch
or select the Select TG > Enter ID menu parameter.
Enter the desired talk group directly using the
keypad. If less than five digits are entered, press the
F2 switch to select the talk group and return to
normal operation.
5.17.5 P25 UNIT CALLS
Unit Calls (also called Individual Calls) can be
placed to a specific radio on a Project 25 channel if the
Unit Call option switch or menu parameter is