PRO-92 Handheld Scanner
(200-0522A) Understanding Scanners Faxback Doc. # 61680
About Your Scanner
Once you understand a few simple terms used in this manual and familiarize
yourself with your scanner's features, you can put the scanner to work for
you. You simply determine the type of communications you want to receive,
then set the scanner to scan them.
A frequency is the receiving signal location (expressed in kHz or MHz). To
find active frequencies, you can use the search function.
You can also search the SEARCH banks, which are preprogrammed frequencies
in the scanner's memory (see "Searching a Preprogrammed Frequency Range"
in Faxback Doc. # 61681 for the frequency list). You can change the SEARCH
frequency ranges.
When you find a frequency, you can store it into a programmable memory
location called a channel, which is grouped with your other channels in a
channel-storage bank. You can then scan the channel-storage banks to see
if there is activity on the frequencies stored there. Each time the
scanner finds an active frequency, it stays on that channel until the
transmission ends. See "Trucking Operation" in Faxback Doc. # 61683 for
terms related to trunking systems.
A Look At The Keypad
Your scanner's keys might seem confusing at first, but this information
should help you understand each key's function.
FUNC (function) - lets you use various functions by pressing this key
along with other keys.
SCAN - scans through the programmed channels.
MANUAL - stops scanning and lets you directly enter a channel
number.
TRUNK - stores the trunking ID code or holds the trunking ID
while scanning.
WX - scans through the 7 preprogrammed weather channels.
PRI (priority) - sets and turns the priority function on or off.
TEXT - lets you input text.
STEP - changes the frequency step or displays step frequency
during search, selects PL or DPL codes when programming
MODE - changes the receive mode (AM, FM, PL, DL, LT, MO, ED,
See "Changing the Receive Mode," Faxback Doc. # 61682).
(key symbol)/LIT - turns on/off the display's backlight or locks/ unlocks
(Light) the keypad to prevent accidental entries.
TUNE - lets you input a frequency and allows you to fine tune
a frequency along with /\ or \/.
ATT (attenuate) - turns attenuation on to reduce the scanner's
sensitivity, or turns it off to increase it.
/\ or \/ - selects the search direction during search or tuning to
a frequency.
SEARCH - lets you search the ten search banks.
L/OUT (lock out) - lets you lock out a selected channel, skip a specified
frequency during search, or lock out a selected ID code
PGM - programs frequencies into channels.
ENTER - lets you complete the entry of frequencies and text.
1/DELAY - enters a 1, or programs a 2-second delay for the
selected channel/search bank, or inputs characters 0
through 9.
2/ABC - enters a 2, or inputs characters A, B, or C.
3/DEF - enters a 3, or inputs characters D, E, or F.
4/GHI - enters a 4, or inputs characters G, H, or I.
5/JKL - enters a 5, or inputs characters J, K, or L.
6/MNO - enters a 6, or inputs characters M, N, or O.
7/PQRS - enters a 7, or inputs characters P, Q, R, or S.
8/TUV - enters an 8, or inputs characters T, U, or V.
9/WXYZ - enters a 9, or inputs characters W, X, Y, or Z.
0 - enters a zero, or inputs characters., -, # _, @, +, *,
&, /, `, $, %, !, ^, ?, >, `, and ^.
(.) - enters a decimal point (necessary when programming
frequencies), space, or hyphen (in Motorola Type I code
setting).
CL - clears an incorrect entry.
A Look At The Display
(See Faxback Doc. # .)
Understanding Banks
Channel Storage Banks
To make it easier to identify and select the channels you want to listen
to, channels are divided into 10 banks (0-9) of 50 (00 to 49) channels
each. Use each channel-storage bank to group frequencies, such as those
used by the police department, fire department, ambulance services, or
aircraft (see "Typical Band Usage" in Faxback Doc. # 61684). For example,
the police department might use four frequencies, one for each side of
town. You could program the police frequencies starting with 000 (the 1st
channel in bank 0) and program the fire department frequencies starting
with 100 (the 1st channel in bank 1). The 1st digit identifies the bank
(0-9). The 2nd and 3rd digits identify the channel within the bank (00-49)
Search Banks
This scanner is able to search 10 search banks. You can also replace a
bank with one of the pre-programmed service bands. (For the default
setting, see "Searching a Preprogrammed Frequency Range" in Faxback Doc.
# 61681).
Note: You can increase the number of preprogrammed frequency ranges your
scanner can receive (up to 100) using an optional PC interface kit
(available at your local RadioShack store).
Understanding CTCSS/DCS
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.
When your scanner receives a CTCSS transmission, PL (private line) appears
When your scanner receives a DCS transmission, DPL (digital private line)
and a 3-digit code appear.
PL Codes
PL codes are low-frequency audio tones that are used to differentiate
different users on the same channel. PL codes appear according to the EIA
standard CTCSS tones, and range from 67 Hz to 254.1 Hz. PL codes are
displayed directly as a frequency.
DPL Codes
DPL codes are similar to PL codes, except they might be transmitted as
either tones or digital codes. Although there are as many 4096 DPL codes,
only about 100 are actually used.
DPL codes appear in the format Dxxx, where xxx is an octal code.
Understanding Your Scanner's Modes
You can program each channel with any of seven receive modes. Each mode
affects how your scanner operates when scanning and receiving
transmissions, and also affects what transmissions you receive when you
set the scanner to the closed mode (see "Open and Closed Modes" in Faxback
Doc. # 61683). The following sections describe each mode and how they
affect your scanners operation. See "Changing the Receive Mode" in Faxback
Doc. # 61682.
PL, DPL and trunking systems all use some form of coded squelch. Coded
squelch techniques involve the transmission of a special "code" signal
along with the audio of a radio transmission. A receiver with coded
squelch only activates when the received signal has the correct "code."
This lets many users share a single frequency, and decreases interference
caused by distant transmitters on the same channel.
In all major metropolitan areas of the United States, every available
radio channel is assigned to more than one user. Public safety radio
systems on the same frequency are usually set up at a distance of 40 miles
apart, or more. This means that you may hear transmissions from a distant
system when your local system is not transmitting. By entering the PL for
a local system, and operating the bank in closed mode, the scanner will
not stop on transmissions from the distant system.
With few exceptions, such as the VHF Aircraft and Marine bands, almost
every other VHF or UHF radio system uses some form of coded squelch. By
far, PL is the most popular mode among non-trunked systems. For most
scanning use, try setting PL mode for all non-trunked channels. If you
operate the bank in open mode, the scanner will display the appropriate
code.
Open and Closed Modes
You can set your scanner to change the way it receives signals. These
settings, called open mode and closed mode, affect how the scanner
receives signals from communications systems that use some type of closed
squelch (such as PL, DPL, LTR, MOT, and ED systems).
You can set each of the scanner's channel storage banks to open or closed
mode.
In open mode, the scanner scans signals transmitted in all systems. In
closed mode, the scanner scans signals transmitted only under the
following conditions:
When the signals are in the FM mode.
When the signals are in the LT, MO, or ED mode and the signal's ID code
matches the programmed ID code.
When the signals are in the PL or DPL mode and the signal's ID code
matches the programmed ID code.
Note: When the signals are in the PL or DPL mode, the scanner receives
all signals on a channel when the ID code is set to NONE.
You can select the users or talk groups you want the scanner to receive in
closed mode.
When you set a channel storage bank to open mode, + (open) appears under
the bank's number while scanning. When you set a channel storage bank to
closed mode, - (closed) appears under the channel storage bank's number
while scanning. Or, OPEN or CLOSED appears while the scanner is in manual
mode or while the scanner is receiving a signal during scanning.
See " Changing the Open/Closed Mode" in Faxback Doc. # 61683 for more
information about setting the open and closed modes.
AM Mode
This sets the scanner to receive transmissions using amplitude modulation
(AM). AM is used for aircraft, military, some amateur radio, and some
government transmissions. When the scanner receives a transmission on a
channel set to the AM mode, it always stops on the transmission.
FM Mode
This sets the scanner to receive transmissions using frequency modulation
(FM). FM is used for most public safety transmissions, as well as
broadcast, business, and amateur radio transmissions. When the scanner
receives a transmission on a channel set to the FM mode, it always stops
on the transmission.
LTR (E. F. Johnson) Mode
You can set your scanner so it decodes the talk group Ids used with
LTR systems. This setting is called the LTR mode.
LTR systems are trunking systems used primarily by business or private
communications service providers, such as taxicabs, delivery trucks, and
repair services. These systems encode all trunking information as digital
subaudible data that accompanies each transmission. Users on an LTR
system are assigned to specific talk groups, which are identified by the
radio as a six-digit number. The number is in the form AHHUUU, where:
A = Area code (0 or 1)
H = Home repeater (01 through 20)
U = User ID (000 through 254)
When the scanner receives a transmission on a channel set to the LTR mode,
it first decodes the LTR data included with the transmission. In the open
mode, the scanner stops on the transmission and displays the talk group ID
on the bottom line of the display. In the closed mode, the scanner only
stops on the transmission if the LTR data matches a talk group ID that you
have stored in the bank's talk group ID list and have not locked out.
LTR systems are frequently programmed so that each radio has a unique ID
code.
Motorola Mode
You can set your scanner so it decodes the talk group ID's used with
Motorola trunking systems. This setting is called the Motorola mode.
Motorola systems are trunking systems used primarily by business and
public safety groups to efficiently allocate a small number of frequencies
(as few as 5) to many groups of users (as many as several thousand). To
do this, each group of users in the system is assigned to a specific talk
group. For example, the east side patrol officers might all be assigned
to talk group 2160. One channel in the system is continuously transmitting
data that identifies which talk groups are active on which channel. In
addition, this talk group information is also transmitted as subaudible
data on each active channel.
When the scanner receives a transmission on a channel set to the Motorola
mode, it first decodes the talk group ID data included with the
transmission. In the open mode, the scanner stops on the transmission and
displays the talk group ID on the bottom line of the display. In the
closed mode, the scanner only stops on the transmission if the talk group
ID matches a talk group ID that you have stored in the bank's talk group
ID list and have not locked out.
Motorola trunking systems come in three categories: Type I, Type II, and
Type I/II Hybrids. Each category displays and uses talk group ID's in
slightly different ways.
Motorola Type I ID's are in the form FFF-SS, where:
FFF = Fleet ID
SS = Subfleet ID
Type I systems are usually organized with different user groups assigned
to different fleets. For example, a valid fleet/subfleet ID identifying
all detectives within a police department might be 000-12 where 000
identifies all police users and 12 identifies the Detective division.
To properly map the raw Type I data to the correct fleet-subfleet format,
you must program the correct fleet map into the scanner. Fleet map
information is widely available on the Internet for most Type I systems in
use.
Type II system talk groups are identified by a 5-digit number. Valid talk
group IDs are divisible by 16. If you try to enter an invalid talk group
ID, the scanner rounds the ID down to the next valid ID.
Type I/II hybrid systems use both fleet-subfleet and 5-digit formats for
talk group ID's.
Note: If the scanner decodes control channel data while receiving
transmissions from a Motorola trunking system, CNTRL appears on the
bottom line of the display.
EDACS Mode
You can set your scanner so it decodes the talk group ID's used with an
EDACS (GE/Ericsson) trunking systems. This setting is called the EDACS
mode.
EDACS systems are trunking systems used primarily by business or private
communications service providers, as well as by some public safety
organizations. EDACS systems transmit active talk group information only
on a dedicated control channel.
EDACS frequencies are organized in a specific order. Each frequency is
assigned a Logical Channel Number (LCN). For the scanner to correctly
switch to an active frequency, you must program the frequencies in LCN
order, starting with Memory 01. EDACS talk group ID's are entered as a
4-digit decimal number from 0000 to 4095.
When there is activity on an EDACS system, that information is sent out on
the control channel. The scanner decodes the ID for the active talk group.
In the open mode, the scanner then goes to the transmission and displays
the talk group ID on the bottom line of the display. In the closed mode,
the scanner only goes to transmissions with ID's that match talk group IDs
you have stored in the bank's talk group ID list which are not locked out.
Because EDACS scanning requires clear reception of the control channel at
all times, EDACS systems tend to have a smaller usable area. An external
antenna can greatly improve EDACS scanning in a fringe area. If you are
having trouble scanning an EDACS system, try manually selecting the data
channel. If you are getting good reception, the scanner will indicate talk
group CTR-01. Try changing your location or using an outdoor antenna to
improve reception.
(GLW EB 9/8/00)
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