E F Johnson Company 2425M80 Benutzerhandbuch

Draft 02 - Sep 1 2015

7-5

The radio may need to be connected to a constant power source to preserve the encryption 
keys in memory. The programming of the Infinite Key Retention parameter determines if 
keys are permanently stored in memory or erased soon after power is removed.

When Infinite Key Retention is enabled, keys are stored in memory and are not lost when 
power is removed. 

With Viking Series mobile models, the keys are maintained for approximately 24 hours 
with this feature disabled. However, a tamper switch causes immediate key erasure when 
the radio cover over the logic board is removed.

When multiple encryption keys are programmed (see preceding information), the Key 
Select option switch can be programmed to allow selection of another key for the current 
channel. This feature changes the PID (hardware location) of the key on the channel for 
Conventional Digital and P25 Trunking Talkgroups, and the change is permanent (cycling 
power or selecting a different channel does not reselect the original key). Therefore, to 
switch back to the original key, it must be manually reselected. Proceed as follows to 
select a key:

1 Press the Key Select option switch and HW KEY (or SW KEY, if optioned/

programmed for software keys) will be displayed. 

2 Rotate the Select switch to display the desired key and then press the Select switch to 

select it. Press the Key Select option switch again to return the display to normal 
operation.

An Erase Keys option switch can be programmed that allows the user to permanently 
erase all stored keys. If OTAR TEK and KEK keys are stored, all keys of both types are 
erased. This function can be used to ensure that unauthorized encrypted calls can no 
longer be placed or received by a radio.