Uniden Bc246t Trunk Tracker Scanner Owners Manual

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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 
operate 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 
inexpensive consumer radios such as GMRS/FRS radios. 
The range is typically 1-8 miles, depending upon the 
terrain and many other factors. 
452 454 455 462 464 465 466 503
506 516 523 526 532 546 565 606
612 624 627 631 632 654 662 664
703 712 723 731 732 734 743 754
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Understanding Scanning
Repeater Operation
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. 
What is Trunk Tracking?
Your BC246T is designed to track the following types of 
trunking systems.
• Motorola Type I, Type II, Type IIi hybrid, SMARTNET, 
and PRIVACYPLUS analog trunking systems, which 
are extensively used in 800 MHz communication 
systems. 
• LTR trunking systems
• EDACS SCAT trunking systems
• EDACS trunking systems
When tracking these types of systems, you might want to 
remember these important points: 
• Your scanner can track more than one trunking 
system at a time and scan conventional and trunked 
systems at the same time. 
Conventional scanning is a simple concept. You enter a 
frequency used by someone you want to monitor into 
your scanner’s memory. For example, the police in your 
area might transmit on 460.500 MHz, the fire department 
on 154.445 MHz, the highway department on 37.900 
MHz, etc. So when your scanner stops on a frequency, 
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Understanding Scanning
you usually know who it is, and more importantly, you can 
stop on a channel and listen to an entire conversation. 
This type of scanning is easy and fun. 
However, as the demand for public communications has 
increased, many public radio users do not have enough 
frequencies to meet their needs, creating a serious 
problem. Trunking radio systems help solve this problem. 
Trunked Scanning
While conventional scanning worked great while there 
were only a few groups wanting to use the frequencies, 
with the advent of smaller, lower-cost radios more and 
more agencies and businesses wanted to take advantage 
of the utility of 2-way radio. As a result, the bands that 
were used most became full, so new users were not able 
to take advantage of the technology as quickly as they 
wanted. 
Trunking solved this frequency shortage by allowing 
multiple groups to use the same set of frequencies in a 
very efficient way. While each type of trunking system 
operates a little differently (see the next few sections), 
they all work on the same basic premise: even in a 
system with a lot of users, only a few users are ever 
transmitting at any one time. 
Instead of being assigned a frequency, as with 
conventional systems, each group is assigned a talk 
group ID. A central computer controls the frequency each 
group operates on...and this frequency selection is made 
each time a user transmits. So, while on a conventional 
system queries, replies, and follow-ups are all on a single 
frequency, they could each be on completely different 
frequencies on a trunked system. This semi-random 
frequency assignment made monitoring such a system 
impossible prior to Uniden’s invention of the 
Trunktracking scanner. 
Not only does your BC246T scan channels like a 
conventional scanner, it actually follows the users of a 
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Understanding Scanning
trunked radio system. Once you know a talk group’s ID, 
you won’t miss any of the action. 
If you are a new scanner enthusiast, you might want to 
read the first part of this manual and use your scanner in 
conventional mode before you begin trunk tracking. 
Understanding scanning fundamentals and terminology 
will make trunk tracking much easier. If you are already 
an experienced scanner operator, you might want to go to 
“Programming Motorola Systems” on Page 54, “Program-
ming EDACS Systems” on Page 58, or “Programming 
LTR Systems” on Page 60 now.
Types of Trunking Systems
Trunking systems divide a few frequencies among many 
different users, but the way that each system does this is 
slightly different. This section describes some of the
technical data behind Motorola, EDACS, and LTR trunked 
radio systems.
Motorola Trunking
While there are different types of Motorola trunking 
systems, they all use the same basic trunking method. 
The system consists of one control channel (or as many 
as 4 per system), plus one or more voice channels 
(typically 10, 20, or 28 total channels). When a user 
presses Push To Talk (PTT) to transmit, their radio first 
sends their talk group information to the control channel. 
The computer then assigns that talk group to a specific 
voice channel and transmits that data over the control 
channel. All radios in that talk group switch over to the 
assigned voice channel and the user can begin speaking. 
This all typically takes place in about a second...the 
person transmitting hears a beep from their radio when 
the channel is assigned and then it is OK to start talking. 
The systems in use are: 
Motorola Type I – the radios send the radio ID, the fleet 
and subfleet talk group ID to the control channel each 
time they transmit. To program a Type I system, you need 
to know the system’s fleet map. The most common fleet 
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Understanding Scanning
maps are included in “Preset Fleet Maps” on Page 105. 
You can also find fleet map resources on the web. 
Motorola Type II – the radios only send the radio ID and 
radio channel code to the control channel. The central 
computer keeps a database of radio ID’s and which talk 
group is assigned to which channel code for each radio, 
so with this system the user’s radio sends only about 
1/3 
the data as a Type I system with each transmission. 
Type II systems do not use Fleet-subfleet talk groups; 
instead they use a 5-digit ID for each talk group. 
Type IIi Hybrid — these systems support a mix of both 
Type I and Type II users. Like Type I systems, you must 
know the system’s fleet map to ensure proper tracking.
EDACS Trunking
EDACS trunking works in much the same way as 
Motorola trunking with a couple of major differences.
In an EDACS system, each frequency used by the 
system is assigned a Logical Channel Number (LCN) so 
that less data needs to be transmitted by the control 
channel. Also, talk groups are assigned in an Agency-
Fleet-Subfleet (AFS) hierarchy. Also, there is one 
variation of EDACS called SCAT that your BC246T can 
monitor. 
Logical Channel Numbers – each frequency used by the 
system is assigned an LCN. This information is 
programmed into each user radio. When a user presses 
PTT, their radio sends their AFS information to the control 
channel. The computer then assigns that talk group to a 
channel and sends the LCN so that all other radios in that 
talk group will switch to the correct channel. To program 
an EDACS system in your scanner, you will need to know 
both the frequencies used by the system and the LCN for 
each frequency. 
Agency-Fleet-Subfleet – talk group ID’s for EDACS 
systems are assigned in a way that makes it easy to see 
at a glance the affiliation of the user. Each radio is 
assigned a 2-digit agency identifier from 00 – 15. 
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Understanding Scanning
For example, 01 might be used by the police, 02 by 
ambulance service, 03 by the fire department, and so on. 
Each agency is then subdivided up to 16 times to provide 
fleet identification, and then 8 more times to identify 
subfleets. 
For example, the complete AFS for the Police 
Department West District’s dispatch channel might be 
01-062. 01 identifies the agency as the police 
department, 06 identifies the fleet as the West district, 
and 2 identifies the subfleet as the dispatch channel. 
While these assignments are somewhat arbitrary and 
vary from system to system, there are many resources on 
the web for finding the assignments for most systems. 
Because of the logical hierarchy of the AFS system, your 
BC246T lets you assign wildcard ID’s that let you, for 
example, use only one ID memory to identify all units in 
either an agency or a fleet.
EDACS SCAT – EDACS SCAT (Single Channel 
Autonomous Trunking) systems operate on a single 
channel and alternate control data with analog voice 
traffic. While your BC246T cannot track ID’s in this 
system, it can eliminate the control data so that all you 
hear is the voice transmissions when you monitor this 
type of system. 
LT R  T r u n k i n g
LTR (Logic Trunked Radio) 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 control 
information as digital subaudible data that accompanies 
each transmission, so there is no separate control 
channel. Users on an LTR system are assigned to 
specific talk groups, which are identified by the radio as 
six digit numbers. 
These numbers are in the form AHHUUU, where: 
A = Area code (0 or 1) 
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Understanding Scanning
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 ID search mode, the scanner 
stops on the transmission and displays the talk group ID on 
the display. In the ID scan mode, the scanner only stops 
on the transmission if the LTR data matches a talk group 
ID that you have stored in the talk group ID list and have 
not locked out.  LTR systems are frequently programmed 
so that each radio has a unique user ID.
I-Call (Motorola/EDACS)
I-calls are direct unit-to-unit transmissions that are not 
heard by other system users. Your BC246T can receive 
I-call transmissions. See “Setting I-Call (Motorola and 
EDACS Systems Only)” on Page 68 for more 
information about monitoring I-call transmissions.
Where To Get 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.  
The Internet is a great source for current frequencies and 
information about scanning. Many web sites have lists of 
frequencies for your area. You can use a search engine to 
find and use them. 
Make a list of the agencies you want to listen to, then look 
up the frequencies and systems used by those agencies. 
Here are a few useful sites:
•http://www.scannermaster.com * - frequency 
resources and home of Police Call.
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Understanding Scanning
You can also call them at 1 800 SCANNER (hours are 
from 10:00 a.m. to 5:00 p.m. Eastern Time Monday 
through Friday).
•http://www.radioreference.com 
* - the Internets 
premier source for user-supported radio system
information.
•http://www.bearcat1.com - frequency information 
from National Communications.
•http://svartifoss2.fcc.gov/reports/index.cfm 
*
 - 
conventional frequency information on file with the US 
Government
•http://groups.yahoo.com/group/BC246T 
* - a group
for people interested in discussing the BC246T.
* - These web sites are not affiliated with Uniden Corporation.
For more information about Uniden and accessories or 
products, visit http://www.uniden.com.
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Included With Your Scanner
Included With Your Scanner
If any of these items are missing or damaged, 
immediately contact your place of purchase or Uniden 
Customer Service at: (800) 297-1023, 8:00 a.m. to 5:00 
p.m., Central, Monday through Friday. 
Setting Up Your Scanner
Owners  ScannerAC Adapter
and other
Belt Clip
V
o
lS
q
l
ManualAntenna
Wrist Strap
BatteriesConnection
Cable
printed material
Included With Your Scanner
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Setting Up Your Scanner
These guidelines will help you install and set up your new 
scanner: 
• If your scanner receives interference or electrical 
noise, move the scanner or its antenna away from the 
source.
• To improve the scanner’s reception, use an optional 
external antenna designed for multi-band coverage. 
(You can purchase this type of antenna at a local 
electronics store). If the optional antenna has no 
cable, use 50-70 Ω coaxial cable for lead-in. 
A mating plug might be necessary for the optional 
antennas. 
• Use an optional mono earphone or mono headset 
with proper impedance (32 Ω) for private listening. 
Read the precautions on the inside front cover of this 
Owners Manual. 
• Do not use the scanner in high-moisture 
environments such as the kitchen or bathroom. 
• Avoid placing the scanner in direct sunlight or near 
heating elements or vents. 
Using Internal Batteries
You can power your scanner using two alkaline, or 
rechargeable AA batteries.
Setting Up Your Scanner
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