Uniden BC246T 사용자 설명서

다운로드
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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 oper-
ate 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. 
Simplex Operation
Simplex systems use a single frequency for both transmit 
and receive. Most radios using this type of operation are 
limited to line-of-sight operation. This type of radio is 
frequently used at construction job sites, and with 
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