Scanner Information

What will I hear on a scanner???

Both the VHF and UHF business bands (and all the services that use them business, schools
and churches – everything from air conditioning contractors to zoos!)
All NOAA weather broadcast frequencies.
Weather satellite frequencies.
Civil Air Patrol search and rescue frequencies.
All FRS and GMRS frequencies.
Three ham bands: 6 meters, and most importantly 2 meters and 70 cm which are the most popular ham bands.
The full marine radio band.
Railroad communications.
Government services in the 162 – 174 band including some frequencies for the FBI, treasury department, National Park services, prisons.
Nearly all professional race car drivers (only a few are on 800 MHz)
Satellite beacons .
46/49 MHz Baby monitors and cordless telephones.
The full commercial aircraft band (which is AM, not FM).

The Commercial Aircraft band is AM not FM – Why?

If the control tower clears a plane to land and two planes think that command was for them, they
will acknowledge the command over the air at the same time. If the radios were FM, the control
tower would hear only the plane with the strongest signal. The serious error would probably not be
caught. But by using AM, if two pilots transmit at the same time, the control tower will hear both,
immediately know there is a problem, and easily correct the situation. Because of its immunity to
noise, FM is preferred and used virtually everywhere a scanner tunes except one band: the
commercial aircraft band.

What is a trunking scanner?

A trunking scanner can make sense out of police/fire/emergency calls you can hear, but trunking systems cannot be followed by a regular 800 MHz scanner. A trunking system consists of several frequencies that are used together on a shared system, typically 8 to 20 frequencies. One channel is a control channel and contains the data that tells all the radios where to tune to follow the conversations that they are allowed to monitor.

Trunking systems have the advantage over conventional, individualized frequencies for each service because the trunking system uses far fewer frequencies, can be shared by a wide variety of services, and permits service-to-service communications (fire fighters can talk to police officers if the need arises. That’s not possible under the old systems where they were on different frequencies).

Radios in a trunking system belong to one or more groups. ID numbers are assigned to the
groups. Many web sites now have lists of these numbers. You hear the group in the scanner and
the scanner displays the group ID number. You can download a list from the Internet which will
identify groups or services whenever that ID number comes up. If you have a scanner that
displays alpha characters, you can program in the names of the groups so that no cross-reference
or look-up is required.

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