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Saturday, May 28, 2016

APCO Phase II - The basic concept.

Many people have asked me - “What is Apco P25 Phase II for”?
 
A good example is the Victoria Digital CFA Network.
 
Currently the CFA Digital network uses an Apco P25 system, each frequency is based on a 12.5kHz step. (Space between each frequency)
At this point - only one channel or talk group can used for the individual frequency.
 
For example - Let’s say A CFA member may talk on frequency 161.0000.
While this frequency is being used, no one else in that general location can use the same frequency.
 
Ok - well thats not entirely true - but we want to keep this simple..disregard CTCSS and NAC codes for a minute.
 
To make better use of the CFA allocated frequencies, you can add Phase II, this means that two users can now talk on the same frequency at the same time without congestion or overlap of voice.
It’s as simple as that.
 
Phase II simply turns 10 frequencies into 20 useable frequencies by allowing a second transmission on the same frequency.
 
Now - a UBCD396XT Scanner is NOT Phase II capable..
A UBCD536-PT and a UBCD436-PT however are.
 
So when the CFA decide to start using Phase II, you may want to update your Scanner..
 
You can find out more here.