Uniden America Corporation UB328 Manuale Utente

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Understanding Scanning
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 
• FRS/GMRS 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. 
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