Understanding Trunking - Radio Shack Pro 94 Manual

8/17/2015
Display Backlight ­ makes the scanner easier to read in low­light situations.
Hypersearch ­ lets you set the scanner to search at up to 300 steps per second in frequency bands with 5 kHz steps, compared
to the normal search speed of 100 steps per second.
Key Lock ­ lets you lock the scanner's keys to help prevent accidental changes to the scanner's programming.
Battery Save ­ saves battery power when the scanner does not detect any transmissions for more than 5 seconds while a single
channel is being monitored. Can be turned off.
Battery Low Alert ­ warns you when battery power gets low by beeping about every 10 seconds.
Key Confirmation Tones ­ the scanner sounds a tone when you press a key, perform an operation correctly, and an error tone if
you make an error. Can be turned off.
Memory Backup ­ keeps the frequencies stored in memory for an extended time if the radio loses power.
Your scanner can receive these bands:
Frequency Step Size
Range (kHz)
29­29.7 5
29.7­50 5
50­54 5
108­
12.5
136.975
137­144 5
144­148 5
148­174 5
216­
5
224.995
Scanning­ the process of stepping through conventional channels in scan banks.
Trunktracking (or Trunking)­ the process of searching for all active talkgroup IDs in trunked systems, in scan banks.
Trunkscanning­ the process of stepping through programmed talkgroup IDs in ID lists, in trunked systems, in scan banks.
Searching­ the process of searching for active frequencies in pre­programmed service searches or the limit search.
Manual Mode­ used for browsing, monitoring, and programming conventional frequencies.
Trunk Mode­ used for trunking and programming trunking frequencies and functions.
Monitor Mode­ used for manually stepping through and moving monitor memories.
Remote Mode­ the mode the radio is in while being controlled by the computer.
Trunking systems let a large group of 2­way radio users (or even different groups of 2­way radio users) efficiently use a set of
frequencies. Instead of selecting a specific frequency for a transmission, the user's radio selects a programmed trunking bank in
the system when that user presses their PTT (push to talk) button. The trunking system automatically transmits the call on the first
available frequency, and also sends (on a different frequency called a Data or Control channel) a code that uniquely identifies that
transmission as a talkgroup ID (or just ID.) So when you are trunktracking a system, you are listening to active IDs transmitting in
the system (each using the first available frequency in the system.) Trunking systems in general allocate and use fewer frequencies
among many different users.
Since the trunking system might send a call and its response on different frequencies, it is difficult to listen to trunked
communications using a conventional scanner. These scanners let you monitor the control channel frequency so you can hear
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Easier to Read Pro 94 Scanner Manual
Mode Band
FM 10­Meter Ham Band
FM VHF Lo Band
FM 6­Meter Ham Band
AM Aircraft Band
FM Military Land Mobile
FM 2­Meter Ham Band
FM VHF Hi Band
FM 1.25­Meter Ham Band
Scanning Terminology
Understanding Trunking
Frequency Step Size
Range (kHz)
406­420 12.5
420­450 12.5
450­470 12.5
470­512 12.5
806­
12.5
823.9875
851­
12.5
868.9875
896.1125­
12.5
956
1240­1300 12.5
Mode Band
FM Federal Government
FM 70­cm Ham Band
FM UHF Standard Band
FM UHF "T" Band
Public Service "800"
FM
Band
Public Service "800"
FM
Band
UHF Hi, 33­cm Ham
FM
Band
FM 25­cm Ham Band
Contents
Contents
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