Police Jurisdictions and Mutual Aid channels

When you buy a scanner, especially if you have us do your programming, you may hear many different types of police agencies. There are the commonly known departments like city police departments and County sheriff’s offices as well as Highway Patrols. There are also many other federal, state, county and local police agencies.

Police agencies’ jurisdictions vary, based on the type of agency, the location they are in and the type of situation. Usually a state agency has jurisdiction anywhere in the state but usually does not enforce local ordinances inside of cities. A County officer similarly has jurisdiction throughout the entire county but again may not have the ability (absent a contract to do so) to enforce city ordinances. Local police usually are restricted to working within their own borders. County and Local police also have the ability to pursue outside their jurisdiction and usually to make arrests for serious violations outside the community. These laws vary from state to state and some agencies are contracted to provide services in other jurisdictions. For instance a small town might contract with the county or state or even a neighboring town to provide primary police protection, that other agency’s police can then enforce the ordinances for each town.

Federal agencies include the FBI, US Marshall, or DEA. There are many federal law enforcement agencies that are tasked with different responsibilities. Some are responsible for building and campus security at federal facilities and bases. The most well-known include the Customs & Border Patrol (CBP) that protect the nation’s borders, the Federal Bureau of Investigation (FBI) and Drug Enforcement Administration (DEA), both responsible for specific law enforcement actions. There are Military Police agencies at most major bases around the world. The Navy also has police and security aboard large vessels like aircraft carriers as well as bases around the country. Most federal law enforcement agencies use encrypted radios for communications, but sometimes non-scrambled radios are used.

Once agency we should mention is not a law enforcement agency at all. Every flyer’s favorite agency, the Transportation Security Agency (TSA) is not a law enforcement agency. TSA officers do not have arrest powers, they refer actual enforcement actions to the local police authority for the airport in question. If an illegal item such as a weapon or drugs, are found the arrest is made by the local or airport police, not the TSA. They do have the authority to deny one access to the transportation they protect. While most associated with airport entry protection they also appear at rail and bus stations occasionally, usually along with local or federal law enforcement agents.

At the next level is the many state law enforcement agencies include the State Highway Patrol, State Police or State Patrol agencies. Like the famous California Highway Patrol of “CHiPS” TV show fame, many states have Highway Patrols. Some states have “State Police” (common in the Midwest and East). Some are called the “State Patrol”, like those in Wisconsin and Minnesota.

State police officers are often called Troopers and often have a more military rank structure with Major’s and Colonels instead of Chief’s at the top end. Most state agencies primary responsibilities include highway patrol, usually on the state’s Interstate and other major highways. Other agencies fulfill support roles for county and local agencies like crime scene processing or manpower for major events. Most of the time State Police agencies do not fulfill local police patrol responsibilities off the highway like city and county police do. Occasionally State Police agencies will do local patrol for communities that cannot support their own police. For example, for years the Illinois State Police patrolled the city of East St. Louis due to the extreme financial distress the city was in at the time. In Massachusetts and Connecticut they often do not have county police agencies so the State Police step in to assist local agencies that elsewhere would be done by the Sheriff’s Police.

There are also other state law enforcement agencies on and off the highways. Some states have a separate police agency for trucking regulation, DMV enforcement, Fish & Wildlife, and other specialized responsibilities. There are also state facility police agencies, like the California State Police (separate from the Highway Patrol) that patrolled the state capitol complex.

All states have Counties, although Louisiana calls them Parishes and Alaska calls them Boroughs. Most of these states have County (or Parish) Sheriff’s Offices (SO’s). Sheriff’s Offices are usually responsible for road patrol, court security and corrections. In smaller counties there are a single County Sheriff’s Office to handle these three tasks. There may be a small Sheriff’s office with the elected Sheriff and a couple deputies to deal with all this. Larger counties may have separate Patrol, Court and Corrections departments. Some counties also have other law enforcement agencies for specialized purposes such as Conservation, County Hospital or Forest Preserve districts among others.

In small counties the Sheriff’s Office might be the only law enforcement agency in the county, there may be no cities in the county or those that exist may not have their own police departments. If an incorporated community has no police department then the Sheriff usually handles law enforcement for the town. Some towns contract with the Sheriff to be their police, often with dedicated officers and vehicles. In some states some or all of the counties have little if any authority. In Delaware and parts of Massachusetts the Counties are pretty much just lines on a map and they do not provide police patrol.

The Sheriff or other county based agencies may also be responsible for other duties such as tax collection, Justice of the Peace, and other administrative services depending on the state and local rules.

Cities, Towns, Villages, Townships (in some states), Boroughs and other municipalities usually have a police department or contract with a neighboring community, State Police or the Sheriff for law enforcement. As a basic service of the municipal government, local police are usually the first response to most emergency situations in the town. They are also responsible for many routine and non-routine services that vary widely from town to town. Local police respond to 9-1-1 calls, document and investigate property and personal crimes, traffic crashes and many other incidents.

There are often specialized police departments for parks, colleges and other schools, public hospitals, and many other taxing districts. Some places even have police departments run by sanitary districts or other large government land owners. In some states in the Northeast there are groups called “Fire Police” which have no actual police power but provide traffic and crowd control at fires and other events.

Local, state and county police departments often participate in Mutual Aid agreements. These allow them to assist each other for emergency and routing incidents and cooperate on incidents that spread over multiple jurisdictions.

OK, so since this is a blog about scanners, what does all this blather mean to me and my scanner? Well, all of these agencies use radios to communicate. If they work together then they need to talk to each other. This is done a couple different ways. The first is by one agency having the other agency’s channels available to them. They could have them added to their own radios or carry a separate radio for that purpose. For example, Mayberry PD might have Mt. Pilot’s channels in their radios.

Another way is to use designated Mutual Aid channels. Most states have some sort of channels made available for police departments to communicate with each other, Illinois has ISPERN and other discrete channels for this purpose. Sometimes this is on a large regional or statewide trunking system like MARCS in Ohio or Palmetto in South Carolina.

Less convenient is the relaying of communications by dispatchers. Mayberry Deputy Fife would call his dispatcher who would call the dispatcher for Mt. Pilot who would then contact the Mt. Pilot officer and relay what Deputy Fife said.

The many large statewide trunked radio systems, like those in Colorado, Minnesota, Illinois, Indiana, Ohio, North Carolina and South Carolina include many shared statewide and regional mutual aid channels to allow multiple agencies to communicate with each other. This allows the Highway Patrol to talk to a Sheriff’s office as well as local police etc.

Before large or regional trunked radio systems, when many states used Low Band (30 thru 50 MHz.) some states had a Statewide Sheriff’s Channel or some other statewide channel or channels that agencies could use to talk to each other. Illinois for example had 39.50, which was called the Statewide Sheriff’s Net. This was a common channel to almost all counties and many city police departments and they could talk to almost anyone else. The Illinois State Police had 42.50, which they used for all State Police Districts and all troopers had that channel. A special switch in the ISP cruisers’ radios allowed them to hear 39.50 and talk back on 42.50, the Sheriff would have the opposite arrangement. This allows each agency to talk on the channel they were licensed for (and that the radio was tuned to) but still communicate with each other. Other states had similar systems. Nebraska had a set of statewide channels for Police, Fire and EMS on 39 MHz.

Eventually Low Band was replaced by “High Band”, usually about 150 thru 160 MHz. and many states replaced the old channels with new VHF channels common to many agencies. Indiana, for example had the old “Plan A” channel of 155.130 (Base) and 154.890 (Mobile) that was a common dispatch channel for many agencies statewide. In addition separate channels were used for police emergencies like 155.475 (the nationwide Police emergency channel) that Indiana called ILEEN and 155.370, which most Midwest states used as “Point to Point”.

Another example was in Illinois, not only do they have a statewide police channel called ISPERN (on the same 155.475 channel as next-door Indiana) but a statewide Fire channel, EMS network, EMA channel and even a channel called IREACH that can be used by any governmental agency to talk to others.

There are some newer nationwide mutual aid channels for police, fire, EMS and mixed operations. Not often used, they are available and detailed in many area’s plans but it is rare to hear them used for the intended purposes. Part of the problem is the clunky naming protocol and huge numbers of channels. V-Fire-31, 8TAC94, UTAC42D and their brethren all are listed in guides but rarely actually used.

Later on, as the large regional and statewide trunked radio systems started being built these systems include many regional and statewide mutual aid channels. Some systems have regional networks that allow any user to talk to any other user anywhere in the area, as well as statewide channels that work anywhere in the state. With the higher capacity of these systems more specific channel assignments can be made to tailor the operation.

Large trunked radio systems do have some drawbacks. They can be complicated to work for many users, and with the bewildering array of channels available that could confuse people to where they may not know what channel to use or how to find it. Like the wide variety of mutual aid channels on VHF, UHF and 800 in the more recent past, the overwhelming choice of channels and confusion about how to access them make it more likely for users to revert to having the dispatcher call the other agency on the phone.

You can dedicate a large chunk of your scanner’s memory to interoperability (big word meaning Mutual Aid) channels and not hear much, if anything for months until one day it starts hopping with a big incident. Check Radioreference.com for the Mutual Aid channels used in your area.

Monitoring Aviation with a scanner

Listening to aircraft and airports with a scanner can be fascinating for both the aviation enthusiast and casual listener. For plane spotters scanners are an invaluable tool to determine what aircraft will be where.

There are several types of monitoring and these can be broken down into several basic types:

  • Airport traffic and ground control
  • En route traffic control
  • Air to Air
  • Ground operations

These same 4 categories are used in both civilian and military aviation; they just use different frequencies.  Military tends to be a lot heavier on the Air-to-Air traffic than civilian aviation but otherwise they are remarkably similar in structure.

Let’s start out at the local airport. There are several types of airports out there that can be pretty well categorized into 2 types: “Controlled” and “Uncontrolled”. Some Uncontrolled airfields have a ground station, some have no radio facilities at all. Most Controlled airports have separate Tower and Ground control channels and busier airports may have several of each.

Controlled Airports

Controlled Airports have a control tower that is open at least part of the day. One or more Controllers are in charge of the movements on and around the airport, the distance of the controlled airspace depends on the local conditions and area. Any aircraft operating to or from or in the vicinity of the airport has to communicate with the Tower controller.

Controlled Airports usually also have a Ground Controller; he controls movements on the ground of aircraft and vehicles on the airfield. Smaller controlled airports sometimes combine the Air Traffic Controller with the Ground Controller but larger or busier airports have separate controllers. Air Traffic Controllers operate on the “Tower” channel and ground controllers operate on the “Ground” channel. If only one person is operating then the controller will often talk on both the Ground and Tower channel at the same time.

Very busy airports, like O’Hare, Atlanta, Phoenix, L.A. etc. may have multiple Air and Ground controllers for different sections of the airport. In Phoenix for example there are Air and Ground Controllers for the north side and different controllers for the south side of the airport.

Each controller has his own frequency assigned just for him. At a small controlled airport there may be a single Tower channel and a single Ground channel. Busy airports may have 3 or more of each.

Controlled airports also usually have an “ATIS” channel. ATIS stands for Automatic Terminal Information Service. ATIS systems transmit continually on a recorded loop and includes such information as local weather conditions, what runways are in use, any special information the pilots might need (like obstructions in the area of the airport etc.) and other important information. These are great to listen to when you first arrive at the airport to watch planes but since it continually transmits you will want to lock it out pretty quickly. The recorded messages are usually a minute or so in length and plays over and over again. When condition changes they will update the ATIS message. ATIS messages are assigned a letter and the next letter up is used when they change the message. After “Z” it goes back to “A”.

Other channels seen at larger Controlled Airports include “Clearance Delivery” (channels used to provide and verify flight plan instructions), “Ground Metering” (channels used to stage aircraft before they are released to move towards the runway for takeoff) and special channels used to coordinate things like fuel trucks, de-icing operations and others. Very busy airports like O’Hare and Atlanta may have dedicated ground channels for gate areas separate from the regular Ground Control channels.

Less busy controlled airports may only operate their control tower for specific parts of the day, usually something like 6:00 AM to 10:00 PM. After hours the “Tower” channel is used as a CTAF channel like as done at uncontrolled airports.

CTAF Channels / Uncontrolled Airports

Common Traffic Advisory Frequency (CTAF) is used at airports without operating control towers. This includes controlled airports when the tower is closed and airports with no control tower at all. The CTAF could be the tower channel (at a controlled airport after hours) or some other frequency, usually a Unicom channel.

Uncontrolled airports have no control tower so all operations are handled by the pilots themselves according to rules and conventions. The CTAF is used to coordinate actions on and around the airport. Usually the pilots will broadcast their intentions on the CTAF channel so other pilots will be aware and can act accordingly. You will hear a pilot say in the blind something like “Cessna N12345 inbound Mayberry 2 miles out for Runway 21, entering right pattern”. This means the Cessna airplane with registration N12345 is 2 miles away from the airport in Mayberry and plans to land on Runway 21 and will enter the airport’s pattern to the right of the runway.

Other aircraft, vehicles on the ground and plane enthusiasts will be able then to look out for a Cessna coming in. If a plane is already doing something that might conflict with out Cessna then he will either hold back and let the Cessna do his thing or let the Cessna know to watch out or even alter his plan to accommodate him. If an airport maintenance vehicle is out working he will be able to tell if a plane is on the way in and keep clear of him or even tell him to watch for him.

Other channels on the Aircraft bands

There are many other types of channels you might come across on the aircraft bands. Some of these are listed below. Some of the descriptions and uses seem to merge or conflict but all in all the whole system seems to work pretty well.

Unicom

Unicom is often misunderstood and confused with other terms like MultiCom and CTAF. Unicom is a radio station that is used to coordinate activities but it is not staffed by a controller. An airport might have a Unicom station staffed by an airport employee or a business on the airport. There might not be someone monitoring the Unicom station at all. The Unicom channel is usually used to coordinate activities such as fuel and tie-downs, requesting ground transportation and other activities. At uncontrolled airports that have a Unicom channel assigned it is often used for pilot reports and coordination but this is more of a Multicom type operation being done on a Unicom channel.

Most controlled airports also have one or more Unicom channels assigned, often 122.950. Pilots can use the Unicom channel to contact service businesses to arrange for fuel, cars, passenger service, tie-downs and other needs.

Multicom

Multicom is similar to Unicom but there is no ground station involved. The only radios used are those in the aircraft and occasionally ground vehicles. Most air traffic operations at uncontrolled airports are actually a Multicom operation being done on a Unicom channel.

Air-to-Air channels

Air-to-Air channels con be fascinating to listen to. The most infamous is 123.450. This is often used for informal chit-chat amongst pilots. Here in the USA it is common to hear pilots exchanging pleasantries or complaining about the weather. Often a group of private aircraft travelling together might use it to coordinate flight speeds and directions.

Over the oceans, in particular the North Atlantic between the USA and UK, airliners are supposed to monitor 123.450 since they are often out of range of traffic control centers.

There are many other air-to-air channels assigned for specific uses, including Search & Rescue (SAR), Balloon operations, and training. In the Phoenix area where there are many large flight schools there are training areas with specific channels assigned to them in a similar fashion to a MultiCom/Unicom channel to coordinate activities there.

Emergency Channels

There are several channels specifically assigned for emergency use. 121.500 is the most well known. Often called “Guard” (since you are supposed to stand guard on the channel) it is the channel that one would switch to in emergencies or if no other channel exists for an important communication. 243.000 is the military equivalent.

121.500 used to be used also for ELT’s (Emergency Landing Transmitter), these are devices that transmit a specific set of beeps when a crash or hard landing is detected. Most of these have moved off to new channels but occasionally one may pop up here and there.

Ground Operations

Many airports have some sort of facilities for fuel, repairs, tie-down etc. These will often use the local Unicom channel to allow pilots to arrange these services. At controlled airports 122.950 is commonly assigned as a Unicom channel for these purposes. Some airports might have alternate Unicom channels for different FBO’s (Fixed Base Operators). Bill’s Aircraft Fuel Company may operate on one channel and Toms Flying Gas might operate on another.

Pilots can be heard calling an airport’s Unicom operator while en route to the airport to arrange a fuel truck, ride for the passengers, or to find out where they want him to park the aircraft.

At uncontrolled airports the CTAF channel is usually the same as the Unicom channel. Pilots can be heard giving position reports, coordinating operations, getting weather reports or saying hi to his buddy.

Controlled Airports usually have more ground operations and associated radio traffic. Besides the Ground controller (who controls all aircraft and vehicular movements from the gates to the runway) and Air Traffic Controller (who handles all the aircraft in the airport’s airspace as well as on the runways) there may be Gate Controllers, De-Icing operations, fuel trucks, and others operating on aviation channels. On regular Land Mobile (business and public safety) frequencies may be all kinds of operations like baggage smashers, porters, aircraft tugs, personnel transportation, security, police, fire and EMS and more. Even the newsstand in the terminal may use radios to allow the clerks to chat.

Ground Control is a fascinating system to listen to. The Ground Controller usually works in the control tower, often on the level above the air traffic controller. He is responsible for any movements on the airfield except on the runway. This includes aircraft and vehicles. The guy out cutting the grass next to the taxiway? He has to get permission from the ground controller to be there and be able to communicate by radio. Same with the guy changing the light bulbs alongside the runway and the fuel truck that has to get from one side of the airport to the other.

The Ground Controller works closely with the Air Traffic Controller so that one doesn’t have an aircraft crossing the other’s area. For example, if a plane needs to cross the active runway while taxiing from one place to another the Ground Controller will coordinate with the Air Traffic Controller to get permission to do that. When a plane has landed and leaves the runway the Air Traffic Controller will tell him to contact the ground controller in order to taxi over to the gate.

Small controlled airports might have a single controller working both Ground and Tower at the same time during slow periods. Large airports might have 3 or more Tower controllers and a like number of Ground controllers working different sections of the airport.

En Route Air Traffic Control

The USA and Canada has several Air Route Traffic Control Centers (“Centers”) scattered about the continent. Each of these Centers are responsible for aircraft movements above a certain altitude for cross country traffic. Small planes that are flying VFR (Visual Flight Rules) under a specific altitude do not normally communicate with Centers but IFR (Instrument Flight Rules) flights and commercial traffic do.

“Centers” are responsible for tracking and controlling aircraft outside of airports and Terminal Areas. Each Center (there are over 20 in the USA) has a specific area to control and all aircraft above a certain elevation must be in contact with the Center. When an aircraft moves from one center to another he is “handed off” and assigned to a new channel. Each center has assigned channels and many remote base station transceivers to allow him to talk to any aircraft in his area, which might stretch for hundreds of miles. Each Center has many channels assigned to it. Center boundaries do not follow state lines, they are set up for the more efficient handling of traffic. Albuquerque Center for example covers most of Arizona and New Mexico as well as parts of Texas.

Operating in somewhat of a similar function as the Centers are TRACONS, or Terminal Control centers. TRACONS are responsible for aircraft going into or out of a major airport and handle it between the Control Tower and Center Controller. They also have specific frequencies assigned to them. They handle “Approach” (inbound to the airport) and “Departure” (leaving the airport) traffic.

An airplane travelling between Chicago O’Hare and Phoenix might start with the Gate controller at O’Hare International Airport, then talk to the Ground Controller there, then to O’Hare Tower. After takeoff he then gets sent to O’Hare Departure at the TRACON, who then hands him off to Chicago Center. Chicago Center hands him off to Kansas City Center, then they send him to Albuquerque Center who hands him off to Phoenix Approach. At a certain point he is then assigned to the Tower controller at the Phoenix Airport and after he lands switches to the Ground Controller there and perhaps finally to the Gate Controller. Each of these controllers have separate frequencies, so the pilot might be changing frequencies 10 or more times.

Larger aircraft usually have the ability to monitor 2 or more channels at the same time and pilots usually have the frequencies they need ahead of time so it is a lot more organized than it may seem.

Flight Service Stations

Flight Service Stations (FSS) provide weather and condition updates, including from other pilots and handle flight plans both on the radio and by other means (phone etc.). There used to be a system called Flight Watch on 122.000 nationwide but these have been combined with FSS services.  If you hear a pilot talking to “Radio” then he is talking to an FSS station.

Air-to-Air traffic

Probably the most interesting thing to listen to for plane enthusiasts is Air-to-Air traffic. This is radio traffic from one aircraft to another. Some of this traffic is chit-chat among pilots and occasionally is more like CB radio than professional communications. 123.450 is a common frequency for this type of chit-chat. There are other channels (sanctioned and otherwise) used for Air-to-Air traffic.

In August each year, before, during and after the huge Oshkosh EAA fly-in there are often many groups of aircraft that fly together to the show. They will invariably find a channel to communicate to each other on.

Some more official communications include channels assigned to Search & Rescue (SAR), firefighting, helicopter coordination, and pilot training.

Most large cities have a local helicopter channel where choppers from local police, news and tourism can coordinate activities. At large events where there are several helicopters present they may arrange a rotation or specific elevations so everyone gets the shots they want safely. I have heard a few times where one helicopter will assume an informal control operation and coordinate entry, exit and rotation for the several news choppers covering a big incident. While competitors, these are professionals and they depend on each other to do their jobs safely. 123.025 is the helicopter channel in many metro areas.

SAR and firefighting operations often involve multiple aircraft. If there is a ground station controlling the activity (such as the Command Post) they communicate with them to arrange entry and exit to the affected area, water drops and where certain aircraft are going to operate. Without a ground control or command post they work these items out among themselves on an Air-to-Air frequency.

In certain areas pilot training boxes are designated and frequencies assigned. An instructor in one aircraft may communicate with the student pilot to perform maneuvers and critique them.

Arinc

Aeronautical Radio Inc., commonly referred to as Arinc, is a provider of various communications services for the airline industry all over the world.  They provide communications services for airlines both en route and at airports.

Navigational Beacons

There is a huge network of navigational beacons around the continent called VOR’s (VHF Omnidirectional Range). There are about a thousand in the USA alone. They transmit continuous low-power signals on 108 thru 118 MHz. and provide pilots with bearing and distance. A pilot can set up on a beacon and use it to guide his aircraft. While this process is being taken over by GPS more and more there are still many VOR stations scattered around the country. The often look like big white traffic cones out in the middle of a field, in areas where suburban sprawl has occurred the VOR might be mounted on a large round platform 30-50 feet above the ground.

Some VOR’s transmit a Morse Code identifier and others transmit recorded or vice-generated weather information.

Military Air operations

While most civilian aircraft operate in the 118-138 MHz. band the military has a separate aviation band from 225 thru 380 MHz. Much of the traffic is pretty similar to its civilian counterparts. Many military air bases have control tower and ground channels and local support facilities, just like civilian airports. Centers and TRACONS have radios with military channels in them. Some civilian airports that host military units or receive military aircraft also have military channels for Tower and Ground operations. Most military bases also have civilian frequency assignments at them for the occasional civilian aircraft that may have to go there or fly in the area. Often the towers or controllers simulcast on both channels at the same time so that military users will know what other aircraft are doing and vice versa. Military tower controllers often talk to civilian aircraft in the area to coordinate flights and clear traffic thru Military Operating Areas or other restricted locales.

What really separates military aviation monitoring apart from civilian is the Air-to-Air traffic. The various branches of the military have Military Operating Areas (MOA’s) spread about the country and offshore waters. These MOA’s are used to practice maneuvers, dog-fighting tactics, formations and other activities. Out west in Arizona and California there are huge bombing ranges and areas for live-fire operations. All these activities operate on the MilAir band and provide fascinating listening. With a huge swath of spectrum (155 MHz.) to play with finding these operations is a hobby unto itself. Some dedicated MilAir listeners dedicate a dozen or more scanners to search out this huge range of channels looking for new activity.

MilAir operations often use a new frequency all the time, rotate thru a couple dozen channels or just grab random frequencies. The operations are often very short and varied so it is difficult to find sometimes, this adds to the fun! While military ground and air traffic control channels usually remain constant the air-to-air and range traffic varies considerably. Some very busy areas (like the Goldwater Range in Arizona) host aircraft from multiple bases and even several military branches and air forces from other nations. They may have established Entry and Exit frequencies to coordinate aircraft going to and from the range and assign routes.

Certain military aircraft will have both civil and military radios, these include units based at or operating at civilian airports or shared facilities. Most large transport and executive aircraft will have both UNH and VHF radios. Smaller military aircraft, especially fighters, may not have civilian radios so are limited to operations at bases and civilian facilities with military channels available.

Callsigns

Every aircraft and station uses some sort of callsign on the radio. Ground stations (Tower, Ground Control Center etc.) usually identify with the airport name or city (“O’Hare Tower”, “Phoenix Ground”, “L.A. Center”, “Cleveland Approach” etc.) while aircraft identify with a variety of methods. General Aviation aircraft usually identify with the registration number, usually with the full number (“Cessna N123AB”) on the first transmission to a new target and with an abbreviated call afterwards (“Cessna 3AB”). Aircraft with some sort of flight number identify with the airline or company name or call sign and flight number. The callsign does not always reflect the name of the company, it may be an historical name or derivative chosen for a multitude of reasons. The callsign “Cactus” for instance was used by US Airways before its merger with American. Cactus had been the callsign for America West and retained when they merged with US Airways. Callsign names may be found on the internet at various sources.

It isn’t just large airlines that use tactical callsigns. Task-specific flights often do too. Skydiving flights often use some sort of callsign like “Jump Ship” or “Skydive”. Medical flights often use “Mercy” to identify as such.

How do I find aviation frequencies?

The best place for aviation channels is the internet of course. There are dozens of sites dedicated to aviation monitoring and plane spotting.

The official data is available at the FCC’s website. You can download almost any information you want there, including airport charts, terminal procedures and more and it is all the official information. They even have charts for military facilities.

Another great resource is RadioReference.com. Between the database and the forums chances are someone has the information you want there. There are also Yahoo Lists, Facebook and other forums and mailing lists dedicated to various facets of aviation monitoring.

The civilian Aircraft band is basically between 108 MHz. and 138 MHz. 108-118 MHz. is mostly beacons and VOR’s along with AWOS stations, there is no two-way traffic there. Air Traffic Control and other two-way operations are on 118-138 MHz.

The Military Band is between 225 and 380 MHz. It used to stretch up to 406 MHz. but the 380-406 MHz. range has been reallocated mostly to other military uses like base operations. There is also some military aviation use of 138-144 MHz. and 148 to 150 MHz.

What scanner do I need?

This is the easy part! All current scanners these days handle the civilian aircraft band; no special upgrades are needed. Most newer scanners also work on the military bands as well. There are however scanners that are better for the Aviation enthusiast.

The BC125AT is ideal for aviation monitoring due to its small size and Service Search features. It is small enough to fit in your shirt pocket and has easy to use Service Searches for both the Civil aircraft band and the Military Aircraft band.

Consolidated Frequency List:

Here is a listing of some of the most common aviation frequencies in use. It is no means complete, be sure to check for local frequencies at www.radioreference.com and other sources.

  • 108-118           Navigational Channels (VOR, Beacons and AWOS)
  • 118-121           Air Traffic Control
  • 121-122           Mostly ground control
  • 122-128           Air Traffic Control
  • 128-138           Company/AirInc use

Here are some interesting discrete frequencies used throughout the country:

  • 121.500           Emergency “Guard” channel
  • 122.000           Flight Watch
  • 122.700           Unicom
  • 122.725           Unicom
  • 122.750           Air to Air
  • 122.800           Unicom
  • 122.850           Multicom
  • 122.900           Multicom
  • 122.925           Multicom
  • 122.950           Unicom           (Controlled Airports)
  • 122.975           Unicom
  • 123.000           Unicom
  • 123.025           Helicopters
  • 123.050           Unicom
  • 123.075           Unicom
  • 123.100           Search & Rescue (SAR)
  • 123.450           Air to Air (chat)
  • 243.000           Military Emergency/”Guard”

How often should you update your scanner programming?

One of the questions we get here at Scanner Master is how often one should update the programming on their scanner. The answer to that depends on a few things, including what kind of scanner you have, the resources available to you (computer, software etc.) and what is happening in your area.

The type of scanner you have is the first question we always ask. ZIP Code type scanners, such as the HomePatrol, x36/SDS type or the Whistler TRX and WS types are pretty easy to update with the free Sentinel or EZ-Scan software. With a Windows computer these can be updated as often as you like at no charge just by running the software and sending the updated data to the radio. Remember that updating the database does not update the Favorites Lists that you may have so if you are using Favorites Lists check them for any changes.

If you do not have a Windows computer or do not want to do this you can always let Scanner Master do the work for you. We sell fully programmed and ready to go SD Cards for your Uniden or Whistler ZIP Code enabled scanner for just $59.95.

On other modern scanners, such as the various Uniden, Whistler, GRE and Radio Shack digital radios (and some analog ones) they can be programmed by computer with the appropriate software and cables. If you have access to programming software then you can update these easily whenever needed. Scanner Master sells programming software for almost all the current scanners and most older ones.  – Read more

The third question relates to whether you actually need to change it or not. There are some places using the same channels they have for 20 years or more, the Chicago Police Department for example is using the same radio channels they were in the 1970’s for the most part. Other areas have changed frequencies or systems several times over the last couple decades.

For ZIP Code scanners we normally suggest that you update the database when you buy the radio and perhaps once or twice a year after that. If you go on a trip and are bringing your ZIP Code scanner with you update the database before you leave. You might have to update the scanner if you know that your targets have changed systems or perhaps they disappeared and you no longer hear them on the channels that once used.

For non-ZIP Code type scanners it is a little more difficult. Since these are pretty much custom programmed for your area you might have to tweak them from time to time to add a new channel or agency. If your targets move to a new system then you would need to reprogram or replace the scanner, depending on whether the scanner is capable of monitoring the new system.

We also suggest that you monitor the forums for your area at Radioreference.com. When things change they are usually discussed there, often in great detail.

As always, Scanner Master will be happy to help you reprogram your scanner, either with a replacement SD Card or by using our main-in programming service.

Got a bad antenna? How to figure it out.

You spent a ton of money on a new scanner and another small fortune on a fancy outside antenna and feedline. Everything worked great until one day the scanner sent silent. Now what?

Here are some steps to try and figure out what happened. Did your target move to a new frequency or radio system? Did the antenna fail? The feedline? Maybe the radio itself isn’t working. Do this stuff and you can figure out where the problem lies.

First let’s do the easy stuff. Program in the local NOAA Weather station into the scanner. These transmit continuously on 162.400 thru 162.550 MHz. This makes them a great way to test your radio setup for proper reception. It is also an easy way to compare antennas and feedlines. If your radio picks up the weather transmitter then at least the system is working properly. Compare your outside antenna to the back-of-set antenna, the outside one should work better. If it doesn’t then there is probably a problem with it.

If you cannot hear your local weather station (and you know that you could before) then you need to figure out if the problem is with the feedline, the antenna or the connectors. First do a visual inspection of the connectors on the radio and coax and look for obvious problems. If you see nothing wrong then check the other and (at the antenna). If possible use an ohmmeter and check for continuity between the two ends of the coax and that the coax is not shorted. Disconnect the antenna from the coax since some antennas show a DC short when connected.

If you can hear the weather channel then the problem is probably not the antenna. It is more likely a programming issue or perhaps your agency has change radio systems. These days it is very common for many agencies to be converting over to large area-wide digital radio systems. It is often less expensive to do that than to replace older infrastructure. Some states have built statewide systems open to all local and county agencies to use. These states include NC, SC, MI, IN, OH, IL, MN, MO and others. Check your local area at the RadioReference.com database and see if there is a new channel or system listed there. Also check at the very bottom of the county page at RadioReference. If there are regional or statewide trunking systems listed check that system for your local agency.

If you find out that your local agency has moved to a new system then it is time for either reprogramming your current radio (if it will work on the new system) or replacing it with one that is compatible. We can help you pick the right radio for your area, just call one of our scanner experts. Don’t throw away the old radio, you can still use it for other things like aircraft, railroads or whatever old channels your agency retained after moving.

Basic Troubleshooting – How to fix a silent scanner

So your fancy scanner no longer works. Is it the scanner itself or did your local agencies move to new channels? Today we will discuss ways to find out.

The first thing I tell callers when they say their scanner is dead is to try the local weather channels. Almost everyone is in range of one of the National Weather Service radio stations on 162.400 thru 162.550. If you try each of the 7 channels (listed below) and nothing is heard then there may well be something wrong with the radio. If you have another scanner or weather radio handy try that one. If the other radio works then there is likely something wrong with the first radio.

Here are the weather frequencies that you can check to see if your scanner is working properly:

  • 162.4000
  • 162.4250
  • 162.4500
  • 162.4750
  • 162.5000
  • 162.5250
  • 162.5500

If the weather channel works on your scanner then we should look to programming. If the radio worked before but no longer hears the local police, fire or other agencies you used to listen to then they may have changed frequencies. Several states have recently updated their wide-area radio systems, if you live in Ohio, Indiana or South Carolina there is a great possibility that this is what occurred. Alternately, some agencies have switched to existing regional radio systems such as these states or those in Illinois, Missouri, Wisconsin, Michigan Colorado, Louisiana and Mississippi among others.

The best thing to do is check the RadioReference.com database and forums. If you recently lost your target there is likely someone else who has also. I had a caller the other day from northern Arizona say his police department disappeared, he listened to them over the weekend and then on Monday they were gone. We found that they had just switched to a new P25 digital system. While it was not yet listed in the RadioReference database it was being discussed in the RadioReference forums for Arizona.

If all this fails and you cannot find the target anywhere by searches with the scanner there are still a couple more tricks. Remember that public safety communications systems are expensive. They don’t go out and buy them on a whim. Purchases of that size usually must be approved by the local boards, City Council, County Supervisors etc. Look at these board’s websites for meeting minutes and agenda items. This is all public information and most places these days post them to the web. You can sometimes find all kinds of interesting information on the systems, sometimes even complete technical details, frequencies and talkgroup information get put up there!

Check with your local officers and administrators. While often they might not be technically savvy they might know that “we switched to the County system” or something. Also look for the type of radio they are carrying or have installed in the vehicle. That can sometimes point to the radio system type they are using.

Once you find out what system they are using and the frequencies etc. reprogram or replace your scanner to match.

Hosting a stream

One of the most popular ways to listen to the local scanner action these days is via a live-streaming service over the Internet. By far the largest source for this is Broadcastify.Com. While this is a great place to listen, it is dependent on someone hosting a scanner for the area you want to listen to. If no one does you can do it yourself. Here is what you need to set up your own feed:

Step 1:    Make sure there is no feed already covering the traffic you wish to stream. If there already is one look at the noted for that feed and see if there is something different that you will do.

Step 2:    If you are not already a RadioReference or Broadcastify member (with user name and password) set up an account. You can set up a free account, paid accounts offer great benefits but are not needed to host a feed. If you are already a member skip this and go to Step 3.

Step 3:    Go to the Broadcastify site and submit a Feed application. They need your information, the channels you plan to stream and some other details. Once you submit your application it takes a few days (usually) for a response, and if approved they provide a code that is entered in your feed software to enable it.

Step 4:    Set up the hardware. This is the computer that you are going to use and the radio itself. You will need an audio cable to connect the computer and radio. If you are using a Uniden scanner you can also connect a USB or serial cable so allow channel tags to be sent along with the radio traffic. See below for the best scanners to be used for feeds.

Step 5:    Set up the software. The software is free from Broadcastify, you can download it there. It is pretty simple to install and set up, print out the instructions that come with it and follow them. If you follow them correctly it will work great!

Step 6:    Adjust the levels. Once your feed is live listen to it and make sure the audio levels are set properly. If the channels you set up are not very active try programming in the local weather channel for a few minutes to use to set the levels properly. Once you have the levels set where they sound best be sure to note the settings in case you need to move something later. Don’t forget to get rid of the weather channel!

What is the best radio for a feed? Well, it is the radio you have that will listen to the traffic you want to stream. Remember, once you commit to hosting a stream that radio must be dedicated to that stream 24/7.

If the radio you use does not have a record jack then you need to set the volume and leave it where it is. Be sure to mark the level with a dab of White-Out in case it gets moved.

For feeds the Uniden BCD15X (analog) and BCD996P2 (digital) are favored by many streamers since they are reasonably priced and have a record jack on the back. The Record jack is ideal for feeds, as the sound level is not affected by the volume control. You set the sound level with the computer’s sound controls and you can use the scanner volume to allow you to listen to the scanner locally without affecting the feed volume. They also support sending channel tags so the listener can see the channel names.

Streaming hints and tricks:

No one likes to hear static, noise etc. Make sure you monitor your stream to be sure that it doesn’t lock up on noise or interference. Make sure the audio levels are good and that the feed sounds good.

How many channels can I stream? The best answer is less is more. If you have a lot of channels or a bunch of real busy ones then the scanner is going to be busy all the time and some channels are going to be missed. Some really busy feeds (like Chicago PD) have just a single channel that is active almost continuously.

What kinds of channels can I stream? These rules are listed in the Terms of Service for the streaming service. Broadcastify has rules against certain tactical or sensitive traffic. Make sure none of the channels you have include the prohibited traffic.

Can I stream 2 radios at the same time? Yes! Set up one radio to the left channel and the other to the right. Possible scenarios are police on one and fire on the other. Make sure you note this in the feed description!

What do I do if the agency doesn’t want me to stream them? Well, that is up to you. Streaming is legal and the agency cannot force you to stop streaming their traffic. They can however add encryption, then it will not be able to be heard at all by anyone.

Broadcastify has a complete set of rules and procedures on it’s page at Broadcastify.com. If you use a different service be sure to read their rules before setting up your feed.

Reading the RadioReference Database

One of the best sources for scanner information available is the RadioReference.com database. This is a huge listing of frequencies used thruout the USA and Canada for all types of two-way radio operations.

If you do your own scanner programming then the RRDB is invaluable for information. It is usually more accurate than the agencies themselves have! Even if you only use a database scanner (like a HomePatrol or TRX) then it helps to understand the database so you will have a better idea of what you are listening to. Remember: The data in your scanner came from RadioReference in the first place.

To read the RadioReference database and understand how it works you need to understand how it works. Without understanding how it is laid out it can be daunting, there is a whole lot of information at your fingertips.

To understand it you need to know a couple things. There are two main types of data available, trunked and conventional.

First we will look at a conventional frequency listing. Then we will look at trunking information. (Conventional means that it is not trunked.)

Here is the frequency page for Lee County Florida. It shows several fields:

  • Frequency       (Actual frequency used or the repeater output)
  • Input               (Repeater inputs)
  • License            FCC Callsign, click on this to see what frequencies and other info is available for it.
  • Type               Base, Repeater, Mobile only etc.
  • Tone                Could be PL, DPL or NAC 9for P25) etc.
  • Alpha Tag       A short tag used on some scanners, akin to channel numbers etc.
  • Description     A longer description of the channel and its use.
  • Mode              FM, AM, Digital etc.
  • Tag                  The classification that the channel falls under.

If you hover over the column title it will tell you what the codes mean.

Since so many areas use trunking systems these days one might miss a lot of the info needed to monitor the area. Look at the bottom of the county’s page to see a list of trunking systems active in the county. If you see one that appears to be used there click on it to see the data. The first part you will see it the basic info:

At the top you will see an info box with the system name, location, type and other info. Below that you will see the System ID’s (some scanners will show the System ID to identify it) and other info.

If you scroll down the page next you will see the trunked system Sites. Sites is where you will find the actual frequencies used by the system. Some systems only have 1 or 2 Sites, others (like the one shown) have dozens.

This is a portion of the Site List for the huge Illinois StarCom21 system that has many sites all over the state. There are several columns:

  • RFSS is the Zone number (RF Subsystem), then the Site Number within the Zone. Sometimes Sties are shown in other contexts as X-YYY (1-012 meaning Zone 1, Site 12) or just XYY (112).
  • Next is the Site Name, usually the city or location the site is located in. The county the site is in follows.
  • Last are the frequencies used at that Site. Some freqs will be shown in red, these are known to be “Primary” control channels (mostly for P25 systems). Other freqs will be in blue, these are known to be “Alternate” control channels. The rest are shown in black, these are not know to be used as control channels but are used for voice. Unless you know for sure otherwise, it is usually best to include all channels of the Site in your scanner.

The last part of the Trunked system information is the Talkgroup List. These are the virtual channels used to allow the correct people to communicate within the system.

The columns here are:

  • DEC (Decimal)           The most common way to identify a talkgroup in scanners.
  • HEX (Hexidecimal)     Another way to view Talkgroups, used mostly by the fleet radios.
  • Mode                          Tells you if it is Digital (D), Analog (A), Encrypted (E) or TDMA (T).
  • Alpha Tag                   The short channel name
  • Description                 More inclusive description of the channel and its use
  • Tag                              The classification (Service Type) for that talkgroup.

By understanding the way the data is laid out you can apply this to your programming and understanding of the systems you listen to.