E F Johnson Company 2425341 Benutzerhandbuch

31

This feature is not available with the 5300 

mobile. It is available with the 5100 portable only.

5.15.1  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.

5.15.2  GROUP ID CODE

Each Project 25 channel is programmed with a 

group ID that determines which group of mobiles 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 and the 
Monitor Mode described in Section 5.3.

5.15.3  NETWORK ACCESS CODE (NAC)

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.

5.15.4  P25 GROUP CALLS

General

P25 Group calls are placed by simply selecting 

the channel programmed for the desired group, moni-
toring 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 mobile 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 Talk Group Assigned To a Channel

If the TG SEL option switch 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 
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 and then press the 

TG SEL option switch.

2. Rotate the Select switch to display the talk group to 

be assigned to that channel. Talk groups are indi-
cated by a unique identification in the alphanumeric 
display.

3. To select that talk group and return to normal oper-

ation, press the TG SEL switch again or press the 
Select switch. If talk group selection has been 
disabled on the channel by programming, the talk 
group does not change, “NO LIST” is displayed, 
and a tone sounds.

5.15.5  P25 UNIT CALLS

Unit calls (also called Individual Calls) can be 

placed to a specific radio on Project 25 channels If the 
CALL option switch is programmed. Only the indi-
vidual ID of the target radio is sent (a talk group ID is 
not sent). The mobiles that can be called are prepro-
grammed in the Unit Call list. 

To receive a unit call, the RF channel of the call 

must be selected or scanned and the correct NAC and 
unit ID must be detected. The ID of the calling radio is 

* This feature requires firmware 1.24.1/2.2.1/3.2.1 or 
later and PCConfigure 1.22.0 or later.