Uniden UBCD396T Scanner User Manual


 
Understanding Scanning
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Conventional Scanning
Conventional scanning is a relatively simple concept.
Each group of users in a conventional system is
assigned a single frequency (for simplex systems) or
two frequencies (for repeater systems). Any time one
of them transmits, their transmission always goes out
on the same frequency. Up until the late 1980s, this
was the primary way that radio systems operated.
Even today, there are many 2-way radio users who
operate using a conventional system:
Aircraft
Amateur radio
UHF/PRS users
Broadcast AM/FM/TV stations
Many business radio users
When you want to store a conventional system, all
you need to know is the frequencies they operate on.
When you are scanning a conventional system, the
scanner stops very briefly on each channel to see if
there is activity. If there isn’t, the scanner quickly
moves to the next channel. If there is, then the
scanner pauses on the transmission until it is over.