UB334 Paper OM reduced size.fm Page 11 Friday, September 9, 2005 11:16 AM
Understanding Scanning
This section provides you with background on how scanning works. You don’t really need to know all of this to use your scanner, but some background knowledge will help you get the most from your UBC69XLT.
What is Scanning?
Unlike standard AM or FM radio stations, most two- way communications do not transmit continuously. Your UBC69XLT scans programmed channels until it finds an active frequency, then stops on that frequency and remains on that channel as long as the transmission continues. When the transmission ends, the scanning cycle resumes until the scanner receives another transmission.
What is Searching?
The UBC69XLT can search for active frequencies. This is different from scanning because you are searching for frequencies that have not been programmed into the scanner. When you select frequency bands to search, the scanner searches for any active frequency within the lower and upper limits you specify. When the scanner finds an active frequency, it stops on that frequency as long as the transmission lasts. If you think the frequency is interesting, you can program it into one of the banks. If not, you can continue to search.
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 1980’s
Understanding Scanning
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