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RF Scanning for Preppers – Part 1, by R.W.
  SurvivalBlog Contributor March 30, 2021 


Quote:Sir Francis Bacon is attributed with saying, “Knowledge is power.” And nothing could be more true than when it comes to prepping for emergencies and SHTF situations. When the forces of nature or the whims of men (or women) turn life upside down, we need to have a plan for reacting. If you’re reading this then you, more than anyone else, understands how true this is. For those who are unprepared it can literally mean the difference between life and death. Shortly after I began writing this article the people in Texas were put to the test with massive loss of power and freezing temperatures that sadly resulted in many deaths.

Signals Intelligence
One area that seems to get little attention in the prepping community is that of radio frequency (RF) communications. While many understand the importance of radio communications, few seem to understand the vital imperative of signals intelligence. I’ve read through many prepping sites and books that talk about how you need to get an amateur radio license and then buy basic ham radio (or CB) gear that allows you to communicate with others.

But what about monitoring what’s going on out there, without ever saying a word? Do you understand the wealth of information that is flying around you, sight unseen? Do you have any idea of the number of local, state, and federal agencies that are broadcasting information free and clear for you to listen to? This includes all kinds of police, fire, and EMS personnel as well as dozens of governmental agencies. Most large businesses own or lease radio equipment to talk back and forth. Our armed forces use many means of communication including satellites but they also rely on good, old VHF and UHF radio systems. Commercial aircraft, railroads, maritime, and public utilities are also favorite monitoring targets. The list goes on and on.

Gathering Reliable Inteligence
All it takes is a bit of education and preparation to put yourself in the position to be a source of reliable intelligence about what’s really going on out there when things go sideways. You will be able to listen to events as they unfold. You will be able to get the word from boots on the ground when bad weather hits or a riot breaks out or an accident closes down a road. You will have the ability to possess the truth and be much less dependent on the lamestream media. If you choose, you can pass along what you have learned to family and friends to keep them informed as well.

What we need to do, then, is to find out what we want to listen to, what equipment we need to listen to it, program our equipment accordingly, learn to use the equipment effectively to monitor intended targets and finally, prepare for the day when an emergency strikes. During a real emergency, we must have the expertise to monitor as well as the power sources needed to keep us running if the electrical grid goes down. Being able to effectively use a radio scanner can provide us with important information that can be found nowhere else and long before it comes across the usual news media outlets.

What Is A Radio Scanner?
For starters, we need to define what radio scanning really is. Put simply, scanning is the hobby of using a radio receiver to intercept signals in order to hear the voice messages being carried on each signal. When we have a radio frequency we want to listen to, say the dispatch channel for the local police, we would program that frequency into a memory channel of our radio receiver. We could also program other channels to listen to the fire and EMS frequencies. A radio scanner now allows those channels to be sampled briefly for activity. This act of going through all of the programming memory channels looking for activity is referred to as scanning. The memory contents are being scanned, sampled one at a time in a continuous loop, until activity is detected. Once an active signal is found, the scanner stops on that frequency to allow us to hear the audio signal and thus listen to what is being communicated.

Another aspect to radio scanning is using that same receiver to sweep through a frequency range to detect transmissions we might not be aware of. Simply put, you program a lower and upper frequency to define a range. The scanner is put into search mode to sweep that range for activity. In this mode, the receiver starts at the lower frequency and steps through the frequency spectrum looking for active signals. If one is found, the scanner pauses on that frequency to allow you to hear the audio signal. Once the signal stops, the scanner resumes the search. When the scanner reaches the upper frequency, it starts over at the lower frequency and begins to sweep that range again for active signals. This search operation continues until you tell it to stop.

These two actions, scanning and searching, allow us to use a radio receiver to scan known frequencies for agencies we wish to monitor as well as search out new frequencies that might be brand new, not well known or perhaps unpublished to help remain clandestine. Those of us who are really into this as a hobby own multiple scanners. Keep in mind that while your scanner is listening to an active signal, it could be missing activity on other active signals. Thus multiple scanners help to prevent missing crucial information by letting each one monitor a particular agency or two. And when emergencies happen, multiple agencies are talking nonstop so there can be a lot to take in.

This is why the die-hard radio scannist will have multiple scanners dedicated to certain agencies or operations. Some scanners might be scanning while others can be searching (advanced radios or radios interfaced to a PC using special software have the ability to log and/or record signal activity to be reviewed later). Don’t even ask how many dozens of scanners, wide-range receivers and ham radio gear I own. (Yes, you read that right and yes, it probably means I should consider counseling) as well as the number of agencies I am able to monitor at a given time.

Analog and Digital Radio Systems
To research the radio that is best suited for our monitoring needs, we need to talk about the current landscape of civilian, commercial, military and public safety communications. In the good old days, radio communications were analog in that your actual voice signal was carried on a radio wave just like an AM radio station. But like everything else, most communication is now digital. While AM and FM radio stations are still around they have been augmented by satellite radio which is all digital. Analog cassette tapes gave way to digital CDs. TV stations used to beam their broadcasts using analog signals but these, too, have been changed to digital to conserve bandwidth thus allowing cable and satellite TV companies to deliver hundreds of channels. The same thing has happened with public and private radio systems — analog has almost entirely been replaced with digital.

For a digital radio system to work, your voice, like other information such as text or pictures, is first turned into a digital format that is again carried by a radio signal. When that radio signal is received, the voice component is extracted and the digital content is turned back into an analog voice signal for us to listen to. If you’re going to monitor the communications in your area, you’re first going to have to figure out which types of radio systems are being used by the various agencies you wish to listen to.

If you live in a smaller, rural area you might be lucky enough to still have purely analog communications. Some agencies use systems that combine analog (for the voice part) and digital (for the control part) communications. And the more expensive systems are fully digital which also allows them to easily encrypt all or selected channels on that system thus preventing anyone from eavesdropping.

As you begin looking into digital radio systems you will hear terms like trunked or trunking. These terms simply refer to a specialized digital radio system consisting of multiple frequencies to carry signals which are controlled by a separate frequency called the control channel which is used to keep the transmitters and receivers in sync as traffic passes through the system. Most agencies today use trunked radio systems and because that control channel is digital, you’ll need a digital or trunking scanner to receive and decode it properly so that you can listen to it.

To start the research process of finding what radio system types are in your area, you’ll want to go to RadioReference.com and look up your area which will list the agencies in your vicinity as well as what type of radio system they use. This website primarily caters to the United States and Canada. Once on the website, hover over Databases then click on Radio Database. From there you can select the county you wish to explore. There you will find blue-outlined boxes containing the owning agency of the radio system and the type of system. System types will be listed like, “Motorola Type II” or “Project 25 Phase 2” or “DMR.” These are what you’re going to need to remember as it will dictate what scanner you buy if you want to listen to those types of systems (see below). Keep in mind that you very well might be able to receive radio traffic from neighboring counties depending on geography and distance. And the more information you can gather, the better.

Scanner Selection
Analog scanners are much less expensive and you can get a nice unit for $150-to-$200. Analog scanners are also much simpler to program and use. But unless you live in the middle of nowhere, you’re probably going to need a digital (trunking) scanner like the rest of us. That’s going to at least double the price of entry as well as require more effort to program and use. Just remember that you get out of it what you put into it. Another consideration in buying is understanding that you’re trying to hit a moving target. Digital communications continue to evolve. And as they do, upgrades are needed to hear new types of systems. A digital-capable scanner from ten years ago will not be able to listen to the most modern radio systems out there today.

As an analogy, when the CD was invented your old cassette player was useless to listen to that CD. If you wanted to listen to that CD you needed to buy new equipment to listen to this new medium. Older scanners were designed to work on older systems and will continue to work on those systems. But sometimes agencies get new system upgrades or migrate to entirely new systems which are foreign to the older scanner rendering it not obsolete but hampered in what it can still receive. The good news is that the newest digital scanners will allow you to listen to all the new digital stuff as well as the old analog systems. So get the best scanner you can afford because you might need to listen to something tomorrow that you aren’t aware of today.

All digital scanners sold today will receive older Motorola, LTR, EDACS and Project 25 Standard (Phase 1) trunked radio systems. Where we run into issues are the newest trunked systems which are branded X2-TDMA, P25 Phase 2, DMR, NXDN and ProVoice. While the first two are quite popular, the latter three are not nearly as prevalent unless you live in a large metropolitan area. You don’t need to be an expert on any of these systems and exactly how they work. You just need to know what they are called so you know what to look for when selecting the scanner that will meet your needs. Be aware that some models come with the option to buy upgrades that allow you to hear more systems than the way it came out of the box.

Thankfully some high-end models can download all radio systems in the entire United States (and sometimes Canada) via a customized database that is usually upgraded on a regular basis with any changes. This greatly cuts down on the amount of manually programming you need to do since all the details are contained within the database. With such a scanner, all you need to do is to input your zip code or geographic coordinates along with a listening range in miles and the scanner will automatically select to scan all radio systems within that defined area. This makes it very easy to get up and running quickly but it is also very hands-off so you don’t really understand how your scanner works. It just does as it is programmed. While that gets you running quickly, you’ll want to learn more so you can tweak what you listen to as undoubtedly this automatic process selects things to monitor that you have absolutely no interest in listening to.

Handheld, Mobile, or Base?
Another consideration is whether you need a handheld, mobile (vehicular), or base scanner model. Many product lines are available in both handheld and mobile / base models. Obviously, each type has its own advantages and drawbacks. Handhelds are easy to take with you and supply them with power but they typically have poorer audio quality and low volume, and their radio receiver is sometimes not as sensitive or more easily overloaded compared to the other types. Keep in mind these are generalities and each radio needs to be reviewed on its own merits.

Vehicular model scanners are typically designed to be hard-wired into the vehicle’s electrical system, have loud audio and options to mount them where desired. They are typically designed to slide into open slots of your vehicle’s console just like an AM/FM radio if you so choose. Base models typically have the best quality receivers in them, and large displays and controls to make them easier to operate. They usually have the loudest and clearest speakers. Base models might be hard-wired to plug into an AC wall outlet but the best ones will use a DC power port with a power adapter, thus allowing multiple options to power them.

Pt.II to follow.
Pt. II


RF Scanning for Preppers – Part 2, by R.W.

  SurvivalBlog Contributor March 31, 2021  
(Continued from Part 1. This concludes the article.)


Quote:Scanner Models
When radio systems were still purely analog, there were many manufacturers vying for your attention to buy their scanning receiver. With the costs of developing digital-capable receive technology and a dwindling user base, the market has collapsed to just two manufacturers of multimode (analog and digital_ scanning receivers: Uniden and Whistler. Uniden, having been one of the pioneers in consumer electronics developing dozens of models over the past 40 years, currently has twelve scanner models available while Whistler offers six.

For those who might want to dip their toe in the water, there are $150 analog models from both companies (Uniden BC125AT and Whistler WS1010) that will allow you to learn a lot about scanning receivers with a minimal investment. These scanners can only monitor analog radio systems but most public safety agencies have long ago moved to digital systems. Most fire and EMS agencies have moved to digital but still keep their dispatch analog channels active. There are still many agencies on analog systems like commercial and military aircraft as well as many businesses. But an analog scanner will do nothing to let you monitor the vast majority of public safety agencies (police, fire, EMS, hospitals, emergency management, animal control, etc.). Just be aware that neither of these two analog models have coverage above 512 MHz because that’s where the vast majority of digital radio systems are found.

If you want to delve into the digital realm of receivers then be ready to part with $300 for the Whistler digital and base models or $400 for Uniden’s comparable offerings. The Uniden offerings (BCD325P2 and BCD996P2) will likely be worth the extra cost as they cover the more popular Project 25 (aka P25) Phase 1 and Phase 2 systems which the Whistler models (WS1040 and WS1065) do not. It’s very likely that you’ll want P25 Phase 1 / 2 coverage but if you’re sure you don’t then you can save some money by going with Whistler.

The next step up is Uniden’s BCD436HP and BCD536HP which sell for around $500. These include support for P25 Phase 1 and Phase 2 systems built-in, with the option of paying to upgrade the radio’s software to receive NXDN, DMR and ProVoice digital systems. These two radios are part of Uniden’s HomePatrol series (along with the HomePatrol-2 model) which come with the entire US and Canadian radio databases programmed into them. All you have to do is punch in your zip code and a listening range in miles, and it will automatically select all systems within that circle of coverage to monitor. Obviously, you also have the capability to hand-program the scanner for the systems you want if you are more of the hands-on type. The automatic option gets you up and running quickly while the manual option allows you to fine-tune exactly what you listen to — and also learn how your scanner actually works.

While DMR and NXDN are optional upgrades for those Uniden models, Whistler’s TRX-1 and TRX-2 come programmed with support for those two radio systems out of the box. But that will set you back roughly $500 and it won’t give you ProVoice support like you have with Uniden’s less expensive offerings.

The cream of the crop today is Uniden’s newest software-defined radio (SDR) offerings called the SDS100 and SDS200. Out of the box they cover just about every radio system out there today (early 2021). They are very slick and sexy radios with multi-color LCD displays that convey a wealth of information (so much so that it can be overwhelming). But they are also the most complicated to understand and use. And, of course, they are the most expensive at $650 to $700.

Obviously, this can be a sizable investment and may be daunting for some. Just keep in mind that wealth of information that can be gained from listening to public safety agencies over a 20 – 25 mile range around you (which can be expanded using a better antenna system — see below.) You’ll have first-hand accounts as incidents happen by listening to highway patrol (both ground and air units), sheriff, local police, fire departments, ambulances and EMS crews, hospitals, security guards, commercial businesses, public utilities, commercial and military aircraft, emergency management personnel, amateur radio, NOAA weather, forest rangers, state agencies, federal agencies (many of which are encrypted), railroads, marine traffic, CB radio, public FRS and MURS radios, and much more.

Speaking of NOAA weather, almost all scanning receivers have the ability to monitor the NOAA weather radio frequencies and if an alert is sent out, these scanners have the ability to emit a loud alert sound to get your attention. While this is beneficial for bad weather like snowstorms, floods and hurricanes, they are particularly useful for those who need to be forewarned of tornado activity as soon as possible.

With the information given thus far, you should be able to make a list of the agencies in your area to figure out which scanner(s) fit the bill. Then, based on your budget, you are in the position to buy an invaluable piece of prepping equipment. If you were sitting across the table from me and asking my advice, I would say one of the best deals right now for preppers is the Uniden BCD325P2. It’s around $400 at the time of this writing and can listen to a large variety of analog and digital systems. But I am put off by the fact that it does not come with interface software leaving you to have to find a software package to use with it because you don’t want to have to program this scanner by hand.

For less than $100 more you can buy the Uniden BCD436HP or Whistler TRX-1. Both of these come with a free software interface package, and are designed to download and install the RadioReference database. I think the extra cost is well worth it since you get the software and database included. This will make it much easier to program right out of the box, and changes to radio systems will be automatically applied to your scanner when a database update is made available online. The biggest difference between these radios is that the Whistler comes out of the box with support for DMR and NXDN while each of these systems is an additional $70 upgrade for the Uniden.

From a prepper point of view, handheld models are the best way to go as they are very portable (if you need to bug out) and are easily powered with AA batteries. If money is no object then you really don’t need to read any of this section. Just lay down your hard-earned cash to shell out for the top-of-the-line Uniden SDS100 (or its equivalent base / mobile model, the SDS200) which are selling for around $700 right now.

Software
While learning to use a modern scanning receiver can be daunting, the process can be made much easier through the use of interface software. Most scanners today are supplied with a PC interface port that allows you to couple it to a personal computer. Depending on the software used, this allows the scanner to be programmed at the very least and some offerings allow for very advanced monitoring, logging, graphing and recording capabilities.

Uniden’s latest scanners can be interfaced with their own Sentinel software package that can be downloaded from their website. This software makes it much easier to program their scanners because it comes with the entire RadioReference website database for the United States and Canada. With just a few clicks you can pick which systems you want to monitor and then those systems are downloaded into the scanner for monitoring.

If your scanner does not come with a supplied software package, there are a number of freeware and paid packages available on the internet provided the scanner supports a PC interface. My Uniden BCD325P2 came with a USB interface cable but I had to find a third party software package to use with it. Without this software I’d have to manually program hundreds of frequencies and other attributes using the radio’s keypad which would have taken many hours of effort via tedious keypresses. With interface software, I can simply use my computer keyboard to type in frequencies, text tags, and so on. Once done I simply connect the scanner to my computer and with the click of a button all of this information is downloaded into the scanner’s memory in seconds.

My Uniden BCD436HP and Whistler TRX-1 both came with a USB interface cable but they also have an onboard SD memory card that comes programmed with the entire RadioReference database of radio systems in the entire United States and Canada. Going to the Uniden website I downloaded their free Sentinel software package while the Whistler software was included right on its SD card. This software allowed me to search for systems to download into my scanner as well as to periodically check to see if there are updates to the RadioReference database or the radio’s firmware. This ensures that my scanner and monitoring targets are always up to date.

Antennas
Your scanner will come with an antenna in the box. But most of the provided antennas are typically poor performers — especially handheld models. If you want to receive many more signals you’ll want to invest $25 or so to get a much better handheld antenna. If most of your monitoring is done on digital systems in the 700 / 800 / 900 MHz range then you can buy a dedicated antenna for those ranges (they’ll typically be touted as 800 MHz antennas). But if an antenna is best for 800 MHz it will do poorly for anything you will want to receive in the VHF bands (30 – 300 MHz) (commercial aircraft, various military and older public safety systems).

If you want an antenna that will receive well across its entire receive range, consider getting a telescoping whip that extends to 2 – 3 feet in length. Just be sure you pay attention to the type of antenna connector on your scanner. In the past, all scanners came with a BNC connector but these days, as radio size is shrinking, more and more are using the smaller footprint SMA connector. Make sure the antenna you choose matches that connector. And yes, there are adapters available to convert one connector type into another but this does make things a bit unsightly.

If you have a base model scanner (or mobile model used indoors instead of a vehicle) consider getting a discone antenna which is designed to maximize signal reception across a wide frequency band. These models typically run $75 -to- $100 dollars and are designed to be mounted outdoors but you can put them inside your attic if you have a wood frame house with a composition or shake shingle roof. (Metal roofs can partially block transmission and reception.) Radio reception is line of sight so the higher you can get the antenna then the more signals it will receive.

Just be sure to use good quality antenna cable like RG6, RG11, or LMR400 for your discone antenna. Using a good discone can allow you to receive a lot more radio activity if that’s what you desire but if you use too long of an antenna cable or cheap quality cable then that cable will actually attenuate radio signals and you could end up receiving less traffic!

Power Options for Emergency Use
Now that we have a radio in hand and ready for action we must prepare for how we will use this resource during SHTF events. With the recent disaster in Texas, if you had lived within the affected region of that state and you went days without power, how long would your scanner remain usable?

If you have a handheld scanner then it likely runs on AA batteries. Do you have a plentiful stock of alkaline or lithium AAs in your cabinet? What happens when all of those AAs are used up? Do you have rechargeable NiMH AAs in stock? When they are depleted, how will you recharge them? Many handheld scanners have a USB port which means you might be able to recharge the AAs inside the radio with a power bank like you would use to recharge your cell phone. Or maybe you have a battery charger that can be run from a portable solar panel or your generator?

If you have a mobile model that is mounted in your vehicle then as long as that vehicle has a supply of gas then you have power to run that scanner (minimize the time you run the scanner off the vehicle battery with the engine not running since you don’t want a dead car battery). The downside is that in order to listen to this scanner you must be in your vehicle. That’s not terribly practical most of the time unless you’re living in your vehicle. Perhaps you’ve planned ahead and have the ability to disconnect this mobile scanner and bring it indoors to use alternate power sources?

If you have a base model scanner or mobile model brought indoors, then how will you power it? If it’s a base model that only has an AC cord then you’ll need a generator or an inverter connected to a DC power source. A more flexible approach would be a base model that has a DC power port along with the appropriate cable that you can hook up to a car, motorcycle or marine battery that you’ve kept on a trickle charger just waiting for the SHTF event. Have you given any thought to calculate how long this setup will give you power to run your scanner? Do you have a way to recharge that battery, once it’s depleted?

Being a prepper means thinking through emergencies to their logical end. What happens if this occurs? What happens if that? Think through what you have and how you will keep it running if something like the Texas event happens and you are without power for several days or maybe a couple of weeks. If this scanner is part of your lifeline to what’s going down out there then you need to give it a top priority after water, food, and shelter. Failing to plan is just planning to fail!

Additional Intelligence
If you want to maximize your radio intelligence-gathering capabilities then you’ll likely want to consider two other types of receivers – wideband and HF. With the advent of digital communications the wideband receiver is becoming less and less relevant. Wideband receivers are made by companies like Alinco, AOR, and Icom these days. They are typically available in base and handheld models but their claim to fame is allowing the reception of any analog radio signal from 100kHz up to 3GHz. While some of the more expensive models do handle a limited number of digital signals, they do not handle digital radio systems like scanners are made for.

A good model to dip your toe into this pond would be the Alinco DJ-X11T which retails for $300. This compact handheld has good performance, an informative display, backlit keypad, 1,200 memory channels and a multitude of receive modes and step sizes. It runs on a supplied lithium battery but also comes with a AA battery holder.
While a wideband receiver may be a luxury for your needs, a decent HF (shortwave) receiver is a must-have as far as I’m concerned. A decent portable model can be had for around $150 while a fully-featured base model can run you over $2,000. To get started, consider a portable model from C Crane, Eton / Grundig, Sangean, or Tecsun. You’ll be surprised by the performance and features that can be had for around $150. Then you’ll have to learn about the differing receive bands and how the propogation changes for daytime and nighttime reception.

You’ll also need to use online resources that will help you find radio programs from around your country and around the world whether for entertainment, music, or news. You’ll be able to tune into signals carrying many different languages but most serious stations dedicate part of their day in broadcasting English-speaking programs even though it’s not their native language. The nice thing is that most HF radios also come with the ability to tune normal AM and FM radio stations. The better ones can demodulate sideband (USB and LSB) transmissions. Some can even tune the NOAA weather radio stations.

And just like scanner radios, these receivers will be much more useful when coupled with a good antenna typically designed for the specific frequency ranges you want to monitor.

Are You Ready?
I believe that a modern scanning receiver along with a decent HF radio are essentials for our prepping needs. If things go badly or perhaps go really sideways, then we’ll need to gather intelligence about what’s going on out there when normal communication channels might not be available. Hopefully, this information has been helpful to you in impressing the importance of this topic and being properly prepared.

But all I can do is tell you my opinion based on my years of experience in the field. The rest is up to you. If you want to head down this path then you have to start by doing some research on what you want to hear and then spending the money necessary to acquire an appropriate scanner. But it doesn’t end there! Don’t just put that glossy box on a shelf and say you’ll get it out and use it when the time comes. That is the worst mindset to have!

You need to spend some good quality time with your new device learning how to use it properly. That doesn’t mean you have to know everything about everything it does. Start with the basics and make a commitment to use it every day for a few minutes to get comfortable in its operation. Over time, tackle new features and build on that foundation. Teach others in your family as you learn and grow so they’ll be educated as well. Do Internet searches to find answers to problems and YouTube is full of videos that can teach you how to better understand your scanner or HF radio.

Part of the task is also learning to understand what you hear. Listening to public safety agencies is challenging at first because they use code words/numbers and signals to keep communications short and understandable when seconds can count. You’ll need to learn the lingo so you can understand what’s being said. Thankfully the internet is full of resources to help you learn to decipher their language. As you learn and gain experience you’ll be amazed at the amount of information that is flying around there on the radio waves that you use to have no clue about. You were blind but now you see!

If I was to make you a “to do” list, then it would look like this:
  • Research the types of radio systems in your area that you want to monitor
  • Pick the best scanner model for those systems
  • Program your scanner by hand and/or using available software packages
  • Buy a better antenna to allow you to receive signals more strongly and receive more signals
  • Use your scanner on a daily basis to learn more and more about it a bit at a time
  • Use your scanner to listen and learn how agencies communicate so you can glean information
  • Plan today for how you are going to keep that scanner running after the power goes out
  • Consider buying a portable HF receiver (for news and entertainment from around the world)

Knowledge is power and you’ll get out of it what you put into it. If the world is going to Hades in a handbasket you’ll want to use every resource you can to gather intelligence to make the best decisions possible. If you’ve properly prepared you’ll have an important resource that will give you a leg up on everyone else. You’ll have direct access to information that cannot be filtered by a news agency or denied by the powers that be.

What has been presented here is just the start of the journey. There is so much more and it’s now up to you to decide how far down this path you’re willing to go. May God bless your efforts and may God bless America! – R.W.

Useful Links

Uniden scanners
Whistler scanners
Universal Radio portable HF radios
Scanner Master scanner radios and equipment
Mark’s scanner page – Easier to read scanner user manuals
RadioReference radio system database
RadioReference Forums
RadioReference wiki
RadioReference US frequencies
Military radio communications