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• Motorola Type I
• Motorola Type II
• Motorola Type IIi Hybrid
• Motorola Type II Smartnet
• Motorola Type II Smartzone
• Motorola Type II Smartzone
Omnilink
• Motorola Type II VOC
• LTR Standard
When you program Motorola/P25 and EDACS system frequencies into the scanner,
one frequency is the control (or data) channel, and the rest are voice frequencies
shared by all the users. There may be 3 or 4 frequencies assigned as (primary or
alternate) control channels but only one control channel will be active at a time.
These scanners will allow you to program just Motorola/P25 control channels into
the trunking system and the voice channels will automatically be found (but not
programmed). EDACS systems need all the frequencies for the system programmed
and with the correct LCN (Logical Channel Number) assigned.
The control channel continually transmits to the field units and has a sound similar to
listening to a boat engine over the phone (in manual mode; you won't hear this when
you are trunking the system.) This control channel is also a good check to see if you
can trunktrack the system. If you can't hear a control channel when you step through
the trunking frequencies (in manual mode) or can hear dropouts or interference,
you either are too far away to receive the control channel and the system or there is
some interference source that will inhibit tracking and reception. Motorola systems
are limited to a maximum of 28 frequencies per site. EDACS systems are limited
to 25 frequencies per site. Motorola and EDACS systems can be either analog,
digital, or mixed (digital and analog talkgroups). Mixed Motorola systems should
be programmed as Motorola systems and not P25 digital systems. That way the
talkgroup options will allow you to select if it is a digital or analog.
LTR systems work a little differently. LTR systems typically do not have a dedicated
control channel. This type of system encodes all trunking information as digital
subaudible data that accompanies each transmission. The frequencies also have to
have the LCN (Logical Channel Number) programmed for the scanner to trunktrack
properly. Each repeater has its own controller, and all of these controllers are
synchronized together. Even though each controller monitors its own channel, one
of the channel controllers is assigned to be a master that all controllers report to.
Each of these controllers sends out a data burst approximately every 10 seconds so
that the subscriber units know that the system is there. This data burst is not sent at
the same time by all the channels, but happens randomly throughout all the system
channels. If you listen to the frequencies of an LTR system in manual mode (not
trunking), on every channel in the system you will hear this data burst that will sound
• Project 25 Standard
• Motorola X2-TDMA
• P25 Phase I and Phase II
• EDACS Standard (Wide)
• EDACS Narrowband (Narrow)
• EDACS Networked (Wide/
Narrow)
• EDACS SCAT
• EDACS ESK
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