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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.

5.17.1  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