Albrecht AE33 H, Руководство пользователя

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English 35
UNDERSTANDING SCANNING
This sectio
n 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 AE33H.
WHAT IS SCANNING?
Unlike standard AM or FM radio stations, most two-way communications do
not transmit continuously. Your AE33H 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.
CONVENTIONAL (ANALOGUE) 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 this was the primary way that radio systems operated.
Even today, there are many 2-way radio users who operate using a
conventional system:
•
Emergency Services (Police/Fire/Ambulance)
•
Freenet
•
PMR 446
•
Marine Radio
•
Aircraft
•
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.
WHERE TO OBTAIN MORE INFORMATION
By itself, this manual really only provides part of what you need to know to
have fun scanning
– how to program and use the scanner.