Uniden BCD325P2, Руководство пользователя

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Quick Search - lets you search from the currently-tuned frequency or channel or
enter a frequency and start searching.
Automatic Channel Setup - accepts frequencies on any valid channel step, even if
it does not fall within the band plan’s default steps.
Configurable Band Defaults - allows you to set the step (5, 6.25, 7.5, 8.33, 10,
12.5,15, 20, 25, 50 or 100 kHz) and modulation (AM, FM, NFM, WFM, or FMB) for
31 different bands.
Attenuator - you can set the scanner’s attenuator to reduce the input strength of
strong signals by about 20 dB per channel, search band, close call band, or trunked
system.
Duplicate Frequency Alert - alerts you if you try to enter a duplicate name or
frequency already stored in the scanner.
Search Lockouts - you can lock out up to 500 frequencies (250 temporary, 250
permanent) in search or close call search.
Built-in Battery Charger - allows you to charge the batteries in the scanner with a
timer to set up to 14 hours.
UNDERSTANDING DYNAMIC MEMORY
CONVENTIONAL SIMPLEX AND REPEATER SYSTEMS
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 inexpensive consumer radios such
as GMRS/FRS radios. The range is typically 1-8 miles, depending upon the terrain
and many other factors.
Repeater systems use two frequencies: one transmits from the radio to a central
repeater; the other transmits from the repeater to other radios in the system. With a
repeater based system, the repeater is located on top of a tall building or on a radio
tower that provides great visibility to the area of operation. When a user transmits (on
an input frequency), the signal is picked up by the repeater and retransmitted (on an
output frequency). The user’s radios always listen for activity on the output frequency
and transmit on the input frequency. Since the repeater is located very high, there is
a very large line of sight. Typical repeater systems provide coverage out to about a
25-mile radius from the repeater location.
UNDERSTANDING CTCSS/DCS/NAC
Continuous Tone Coded Squelch System (CTCSS) and Digital Coded Squelch
(DCS) are two methods used to prevent interference by other radio communications.
Your scanner can receive transmissions that use these codes (or more commonly
referred to as tone codes).