RadioShack Pro 94 Handheld Scanner Owners Manual

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TRUNKING OPERATION
The PRO-94 scanner tracks transmissions that use the
Motorola Type I, Type II, hybrid, and, Ericsson EDACS
analog trunking systems. Remember these important
points when tracking transmissions:
• Your scanner cannot scan trunked system and
conventional frequencies at the same time.
• The frequencies for many of the 800 MHz, 900
MHz, and EDACS public safety systems are listed
in the separate “National Public Safety Trunked
System Frequency Guide” included with your
PRO-94.
TYPES OF TRUNKING SYSTEMS
This trunking scanner monitors two basic types of sys-
tems — the Motorola Type I/Type II or hybrid System,
and the Ericsson EDACS System. Instead of selecting a
specific frequency to transmit on, a trunked system
chooses one of several frequencies in a 2-way radio us-
er’s talk group when that user presses their PTT (push
to talk) control. Thus, trunking systems, in general, allo-
cate a few frequencies among many different users. Mo-
torola Type I and Type II systems achieve the same
thing in a slightly different way. One important distinction
between these systems is the amount of data transmit-
ted by each radio when the operator pushes the PTT
control. A Type I system, transmits the radio’s ID and its
current affiliation or the trunk system to which it belongs.
A Type II system only transmits the radio’s ID. 
Why the difference? In Type I systems, each radio in
the trunk group individually transmits its own affiliation,
while the trunk system maintains a database that deter-
mines each radios affiliation(s) in Type II systems. 
Another difference between the systems is that Type I
systems are arranged in a fleet-subfleet hierarchy. For
example, it is possible for a city using a Type I system
to designate four fleets, each with eight subfleets. 
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The police department, fire department, utilities group,
and city administration could each be a separate fleet.
The police might decide to further divide its fleet into
subfleets, such as dispatch, tactical operations, detec-
tives, north, south, east, and west side patrols, and su-
pervisors. All the available police radios would then be
assigned to one of the police subfleets, letting the po-
lice centralize their communications and control the
type of users on a single system. Determining the exact
fleet-subfleet hierarchy for a particular area is referred
to as 
fleet map programming.
The disadvantage of a Type I system is that the brief
burst of data sent when a user transmits must contain
the radio’s ID, its fleet information, and the subfleet in-
formation as well. This is three times the amount of
data a Type II system radio sends. Since the data ca-
pacity of Type I systems is limited and the total amount
of data increases with each user, Type I systems usual-
ly accommodate fewer users than Type II systems.
Nevertheless, Type I systems are still in use.
There are also 
hybrid systems which are a combination
of Type I and Type II. Your scanner is preset to monitor
Type II systems, but you can change to Type I or a hy-
brid of Type I and Type II systems by selecting a pre-
programmed fleet map or creating a custom fleet map
for your area (see “Scanning Type I and Hybrid Trunk-
ed Systems” on Page 55).
SETTING THE SCANNER TO THE 
TRUNKING MODE
Press TRUNK to switch between conventional scanning
and trunking operation.
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SETTING SQUELCH FOR THE
TRUNKING MODE
Your scanner’s squelch setting is automatically adjust-
ed during trunking, which means it is not necessary to
manually adjust squelch while scanning trunked trans-
missions. However, the squelch setting can affect how
fast your scanner acquires the data channel, and, in
some instances, can prevent your scanner from acquir-
ing the data channel at all.
We recommend you set 
SQUELCH fully clockwise be-
fore selecting a trunked bank.
Note:
 Change this setting as needed for the best per-
formance in your area.
STORING TRUNKED 
FREQUENCIES
Before you set up your scanner to track a trunked sys-
tem, consider the following:
• The following frequency ranges are valid for the
trunk systems indicated.
Motorola Type I and Type II system:
935.0125–939.9875 MHz
851.0000–899.9875 MHz
(except cellular frequencies)
406.0000–512.0000 MHz
137.0000–174.0000 MHz
Ericsson EDACS system:
900.0000–956.0000 MHz
806.0000–868.9875 MHz
406.0000–512.0000 MHz
137.0000–174.0000 MHz
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• You can designate any of your scanner’s banks as
either a trunk scanning bank or conventional scan-
ning bank, but you cannot mix the two modes in
one bank. 
• The PRO-94 can scan multiple trunking systems. if
a system is inactive for 5 seconds, the PRO-94
starts scanning the next selected trunk bank. 
Follow these steps to select, program, and store trunk-
ed frequencies.
1. Press 
PROG then TRUNK. TRUNK appears and
one or more bank numbers flash.
2. Press the number key (1–10) of the desired target
storage bank. Select one of the trunk systems by
repeatedly pressing
 W
 or V
 to select a trunking
system type, then press 
E (SVC). The scanner then
automatically selects the first channel in the
selected bank.
Note:
 You can select from the following six sys-
tems :
3. Use the number keys to enter a valid frequency
within the trunk system, then press 
E (SVC). BANK
and the bank number, the channel number, and E
(EDACS) or M (Motorola) appears depending upon
the trunk system selected.
You See Trunk System
E1Motorola Type I, 800 MHz fre-
quencies
EdEDACS frequencies
E2 – 800Motorola Type II, 800 MHz fre-
quencies
E2 – 900Motorola Type II, 900 MHz fre-
quencies
E2 – HiMotorola Type II, VHF frequen-
cies
E2 – UHFMotorola Type II, UHF frequen-
cies
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Notes:
 
• If you enter an invalid frequency (outside the
selected range), the scanner beeps, the channel
number flashes and 
Error appears. If this
happens, press 
MON/CLR (•) to clear the fre-
quency, then repeat the entry.
• For EDACS systems, you must enter the fre-
quencies in logical channel number (LCN) order.
• If you try to enter a duplicate frequency in a
bank, the scanner beeps and the channel which
was previously stored appears.
• It is very important that you enter all the listed
frequecies for the selected agency in Step 3.
Otherwise, trunking will not occur when you
press 
SRC (see Step 6).
4. Press either 
PROG or V
 to select the next channel
in the bank.
5. Repeat Steps 3 and 4 until you enter all desired
frequencies in that bank.
6. Press 
SRC to begin searching for the trunk’s data
channel (the channel that controls the trunk).
SEARCH flashes as the scanner searches for the
data channel.
As 
the scanner looks through the frequencies, you
see them on the display. When the scanner finds
the controlling data channel, the scanner begins
trunking.
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SCANNING A TRUNKED BANK
Once you have stored frequencies for a trunked sys-
tem in one or more of the 20 available banks, and while
the PRO-94 scans conventional (non-trunked) frequen-
cies, follow these steps to switch to trunk scanning. 
1. Press 
TRUNK. The numbers of the banks which
have stored frequencies flash and 
BANK and
TRUNK appear.
2. Press V
. Only the bank numbers you programmed
as Motorola (
M) systems flash. If you want to scan
an EDACS (
ME) system, press V
 again. Only the
bank numbers you programmed as EDACS sys-
tem flash. Press the number key of the trunked
bank you want to scan, then press 
SRC. The scan-
ner searches for a data channel. When the scan-
ner finds it, the scanner begins trunking.I
3. To return to conventional scanning, press 
TRUNK.
Hint: 
While scanning, you may not know exactly to
whom the talk group IDs are assigned until you listen
awhile. To locate talk group ID lists for your local po-
lice, fire, and other agencies, refer to frequency guides
available at your local RadioShack store or on internet
sites such as 
www.trunkscanner.com. You can also
determine the type of agency you are listening to after
a short while, be it a police, fire, or emergency medical
2-way radio user. Once you have identified the type of
service, note the associated talk group ID of that unit
for future programming. See “Identifying a Trunked
Frequency” on Page 48. Determining the service asso-
ciated with an talk group ID might take awhile, but dis-
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covering the ID owner of each signal is half the fun of
trunk scanning!
Turning a Trunked Bank On or Off
Press DATA (ALT) during trunk scanning. The selected
trunked banks appear. Press the bank number (
0–9), to
turn the desired bank on or off.
Skipping a Trunked Bank
You can skip to the next trunked bank during scanning
by holding down 
SRC (LIMIT) for about 3 seconds.
Turning the Status Bit Ignore
(S-bit) On or Off
You can set how your scanner works with status bits
(also called S-bits), letting you control how the scanner
interprets and displays talkgroup IDs.
The last four bits of a Motorola Type II talkgroup ID (a
binary 16-bit code) are the status bits. In some sys-
tems, status bits identify special situations (such as an
emergency status). 
Your scanner is preset to assume that the status bits in
a talkgroup ID are set to 0 and ignores them. For exam-
ple, when the scanner receives the talkgroup ID
010111001110 0011, 
it reads the ID as 010111001110
0000
 and converts the first 12 bits of the ID to 23776
(the talkgroup ID). However, since the status bit value
is 3 (0011 converted to decimal equals 3), the ID is ac-
tually 23779.
If you are scanning a Motorola Type I system and do
not have a fleet map for that system, you might have to
turn off status bit ignore in order to determine the prop-
er fleet map. 
Important:
 If you are scanning any system other than
a Motorola Type I system, be sure status bit ignore is
set to 
ON or you will miss some transmissions.
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Follow these steps to turn status bit ignore on or off.
1. Hold down 
SCAN until the current status bit ignore
setting (
ON or OFF) appears.
2. Press s
 to select 
ON or t
 to select OFF, then
press 
E (SVC).
Identifying a Trunked Frequency
While ID scanning (looking for IDs within a trunked sys-
tem) or performing an ID search, press W
 to see the
current trunked frequency. (The frequency flashes
twice.) Then hold down W
 until a confirmation tone
sounds and the ID and the frequency alternately ap-
pear. To return to normal operation, press W
. 
Selecting the EDACS Talk Group
ID Format
The EDACS system uses two group ID formats: Deci-
mal and Agency-Fleet-Subfleet (AFS). If you use a list
of IDs shown in one format (for example AFS) and the
ID you want to receive is in the other format (for exam-
ple, decimal), press 
SVC (E) to switch to the decimal for-
mat. The ID appears in decimal format. 
E flashes on the
display when the decimal format is selected.
EDACS Talk Group ID Range Search
To search EDACS IDs faster, set a range for the Agen-
cy or Fleet listings. Enter the Agency (or the Agency
and the Fleet) listing numbers using the number keys,
then press 
SRC (LIMIT). Note the following examples.
Example 1 
Agency = 01
Press 
0 1 . SRC (LIMIT)
01--- appears during search.
Example 2
Agency = 01  Fleet = 01
Press 
0 1 . 0 1 SRC (LIMIT)
01-01- appears during search.
To stop an ID range search, press 
SRC (LIMIT).
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Using HOLD to Monitor an
Active Talk Group ID
Follow these steps to stop scanning and keep the scan-
ner tuned to a desired ID. 
1. Press 
HOLD (A/B). HOLD appears and the scanner
stays on the current ID.
2. If you want to listen to (and hold) a different ID, use
the number keys to enter that ID.
3. Press 
HOLD (A/B) again. HOLD flashes, then the
scanner monitors the ID.
4. Press 
SRC to resume searching for a data channel
(trunk scanning).
Temporarily Storing a Talk Group ID into 
the Monitor ID Memory
To store a talk group ID into a temporary monitor mem-
ory, press 
MON/CLR (•). This lets you store the ID prior
to moving it into a list memory. Press 
SRC to resume
searching.
Note:
 To program the ID stored in the monitor ID mem-
ory into the ID scan list, see “Moving Talk Group IDs to
Talk Group ID Lists” on Page 54.
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Locking Out Talk Group IDs
Many municipal and commercial services use trunk
systems to transmit signals from such devices as water
meter transmitters, door alarms, and traffic signals.
Some signals are encrypted, as well, and most are not
voice signals. Since all these are assigned IDs just like
other users, you may want to lock out reception of
these ID signals. You can lock out up to 100 IDs at one
time.
Note: 
If you lock out an ID while searching, it is also
locked out of the scan list(s). See “Using Talk Group ID
Lists” on Page 52.
To lock out an ID, press 
L-OUT (S/S) when the ID ap-
pears. The ID is locked out, and the next active ID ap-
pears.
Unlocking a Single Talk Group ID
1. Hold down L-OUT (S/S) until you hear two short
beeps.
2. Repeatedly press W
 or V
 to select the ID you want
to unlock.
3. Press 
L-OUT (S/S). The ID is unlocked, and the
n e x t  l o c k e d  I D  appears.
4. Press 
SRC (LIMIT) to resume the scanner’s previ-
ously selected function.
Unlocking All Talk Group IDs
Hold down L-OUT (S/S) while searching until you hear
two short beeps, then press 
E (SVC) to unlock all the
IDs at once. The scanner beeps twice. Press 
L-OUT/SS
to resume the search.
Note:
 When you unlock all the IDs, the scan list ap-
pears. Press 
SCAN to scan the IDs stored in your scan
lists or press 
SRC (LIMIT) to resume the scanner’s previ-
ously selected function. For more information about
scan lists, see “Using Talk Group ID Lists” on Page 52. 
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