Civil Safety: Analog and Digital Radios in Times of Crisis
To say that modern people are accustomed to the ability to connect with others virtually anywhere and at any time is an understatement. In fact, modern people have become dependent on communications, on the ability to receive and transmit information in real time.
Let's imagine that at some point, for some reason, we lose communication - there is no cellular communication in general and no mobile internet in particular, landline phones and fixed internet lines are not working.
How realistic is this?
Well, many people in Russia have already experienced outages or severe restrictions on mobile internet service. According to some reports, complete mobile service shutdowns are already in effect in some southern regions. As for landline networks, they will only operate as long as there is power; during a blackout, all types of public service will be shut down.
We previously examined the possibilities for individual electricity supply to citizens in the materials Civil Security: Electrical Energy Storage Devices и Civil Security: Your Own Power Plant.
There's no doubt that in the event of any major global communications outage, a large portion of the population will experience severe stress, leading to illogical and irrational actions—after all, even checking on the health and well-being of loved ones will be impossible, and in a crisis, this isn't just an inconvenience, it often poses a risk to life and health.
Experience from various crises, including wars and armed conflicts, regardless of their geography, suggests that communication is one of the most important factors for survival.
Fortunately, the opportunities for self-sufficiency in communications for ordinary citizens in our time are higher than ever before. stories, and today we will talk about them in more detail.
Radio stations (walkie-talkies)
Naturally, the first thing that comes to mind when the topic of communications is mentioned is radio stations or walkie-talkies (we will use both designations from now on). Indeed, a vast range of walkie-talkies is currently available to ordinary citizens and is freely available in our country.
Of course, when talking about walkie-talkies, we should only consider those whose use does not require any licenses or skills. Accordingly, there can be no talk of any walkie-talkies for communication on medium and short waves - no one will buy them, get a radio amateur license, deploy and configure bulky antennas for communication with wave reflection from the ionosphere, and so on, and so forth.
The feasibility of using CB radios, primarily used in trucks, is questionable. Although truckers' radios can be used without a license at 27 MHz with amplitude modulation, and their theoretical range can reach several tens of kilometers, in practice they require rather bulky antennas to ensure long-distance communication, and their effectiveness in urban areas is extremely limited due to their long wavelength, which is unable to penetrate obstacles.
CB radios are most often produced in a car version.
However, if your task is to organize communication between two points in an area not built up with high-rise buildings, then why not?
But, still, our priority will be UHF and VHF radios.
UHF (400–520 MHz) and VHF (30–300 MHz) radios are sold freely in our country. They also allow free communication on dedicated channels. However, power is limited to 0,5 watts. However, these restrictions are likely to be less strictly enforced during special periods. A significant number of radios currently support both UHF and VHF bands (usually not fully), and the most basic solutions cost less than one thousand rubles each.
As always, cost is one of the most significant factors. For example, Motorola, Hytera, YAESU, and similar radios boast very high specifications and build quality, but their prices start at tens of thousands of rubles, making them unattractive for most people. Ideally, we need more than just one radio, but one for each family member. Again, if finances allow, then why not?
We have already spoken about this before on the use of civilian radio stations in the area of a special military operation (SMO)In principle, everything said in that article is also entirely relevant to the civilian use of radios in crisis situations.
However, over the past few years, the communications market has seen some changes, such as the introduction of radio stations based on the BK4819 chip, which can now compete with inexpensive superheterodyne solutions in terms of noise immunity.
Thus, in essence, we can now identify two basic options that are optimal for use by citizens in extreme situations: one model of an analog radio station and one model of a digital radio station.
Analogue and digital
The first option is the currently popular, practically "people's" analog radio station, the Quansheng UV-K5(8) V2. Thanks to its circuitry based on the BK4819 chip, it boasts a truly enormous receiving range: 19 to 999 megahertz (MHz), albeit with some narrow bands. The Quansheng UV-K5(8) V2 delivers up to 5 watts of power.
A huge number of firmware updates have been created for these radios, significantly expanding their functionality, providing the ability to scan with a graphical display of signal strength, capture signal frequencies with subtone detection, and many other features.
A wide range of accessories are also available for the Quansheng UV-K5(8) V2 radios, including adapters for 18650 batteries, adapters for powering from a car cigarette lighter, and much more.
Analog radio station Quansheng UV-K5(8) V2
Quansheng UV-K5(8) V2 radios start at two thousand rubles when ordered in Russia, and are potentially even cheaper when ordered from abroad. This means that for a family of three to four, including accessories, you can expect to spend around ten thousand rubles. Radios with the Quansheng UV-K5(8) V2's capabilities were once prohibitively expensive, but now they're affordable for virtually everyone, yet most simply don't need them.
Another additional feature of the Quansheng UV-K5(8) V2 radios is a scrambler—analog speech encryption, although its effectiveness is extremely limited. On the other hand, the scrambler alters the voice, making it sometimes indistinguishable between a child and an adult, which can be useful.
The second option is the TYT MD390 digital radio. According to publicly available data, these radios are actively used by our troops in the SVO zone; an alternative firmware version, "Veda," has even been created for them.
The main difference between digital radio stations is that while an analog radio station can be listened to by anyone with a radio receiver that supports the required frequency, the signal from digital radio stations requires decryption, which can be extremely difficult or even practically impossible when using AES 256-bit encryption.
Digital radio station TYT MD-390
As with the Quansheng UV-K5(8) V2, due to the widespread use of TYT MD-390 radios, a significant number of firmware updates and accessories have been released for them. The maximum power of TYT MD-390 radios is 10 watts, and versions are available with or without a GPS module and several encryption options.
The cost of the TYT MD-390 radio station is approximately eight thousand rubles, meaning that for a family of three to four people it will be around thirty thousand rubles.
Selection criteria and operational nuances
Which radios should you choose?
Of course, secure communications are much better than open ones, but for the vast majority of citizens, this isn't such a critical factor. Ultimately, it all comes down to financial means and motivation: if you have the means and desire, digital radios are better; if not, at least analog ones.
One thing is certain: it is better to have at least some radios than to have none at all.
What is the communication range of the above mentioned Quansheng UV-K5(8) V2 and TYT MD-390 radio stations?
This is the most difficult question. The problem is that the concept of "coverage area" doesn't apply to radio stations. That is, it's impossible to say with certainty that a radio of a given power, at a given frequency, will guarantee communication over a given range.
There are many factors involved: the airwaves being overloaded with various sources of electromagnetic waves, the terrain (flat or hilly), the presence and type of natural and artificial obstacles (trees, buildings, structures, etc.), and the location of the radios (high or low).
Sometimes you can get a connection on the radios at a range of tens of kilometers, but sometimes the connection is lost after just a couple of kilometers. Sometimes a step to the right means there's a connection, a step to the left means there's no connection, a radio held at chest level means there's no connection, and raising your hand means there's a connection.
Digital communication is cleaner, but when the signal deteriorates, it simply drops out. An analog signal can be cluttered with interference, but in dire straits, it's still somewhat understandable. Almost all digital radios have an analog mode. The higher the squelch setting, the cleaner the signal, but the more the range drops. However, the squelch can always be "unlocked" with the press of a dedicated button.
But if many people use walkie-talkies at the same time, the communication channels will quickly become clogged, since there aren't that many authorized frequencies?
Firstly, it depends on the “depth” of the crisis; in some cases, restrictions on the use of frequencies by the population will no longer have any particular significance.
Well, secondly, in radio stations, including those mentioned above, there is a function such as CTCSS / DCS codes (subtones), using which you can isolate your communication channel from others - anyone who has CTCSS / DCS turned off will hear you, but you will not hear those who do not have CTCSS / DCS installed or have different ones installed than you.
It all seems complicated, but in reality you quickly get used to using radios, and if there is no alternative...
Satellite communication via radio
It sounds absurd, but in fact it is quite possible.
The thing is that almost fifty years ago, the US Navy deployed FLTSATCOM analog communications satellites into geostationary orbit – the first satellite was launched in 1978, and the last in 1989.
FLTSATCOM satellite image
The FLTSATCOM satellites weigh approximately two tons, and their primary payload consists of 12 transponders operating in the UHF/SHF uplink and UHF downlink frequency ranges. The receiving parabolic antenna, 4,9 meters in diameter, is made of silver-coated mesh. The transmitting antenna is mounted on a separate mast, and power is supplied by 1,4 kW solar panels.
FLTSATCOM satellite coverage areas
These satellites operate with analog signals, have no protection, and anyone can communicate through them, provided, of course, they have the necessary equipment.
Commercially available Argut A-36 radios can be used as transceivers, and Zastone M7 radios can also be used with minor modifications. The easiest way to listen to FLTSATCOM satellites is with an SDR receiver. For the antenna, use a Yagi antenna, either a cross-Yagi or a circularly polarized spiral.
Radio stations "Argut A-36" (left) and Zastone M7 (right)
Thus, thanks to the FLTSATCOM satellites, voice communications can be provided across a significant portion of the Russian Federation and the former Soviet Union. Protocols such as APRS can be used to transmit GPS coordinates and text messages, while HF-FAX or SSTV protocols can be used for image transmission, although this is more complex than simply "chatting."
Cross-Yagi antenna
But what if FLTSATCOM is used by spies?
These will be extremely stupid spies, unaware that their messages will be picked up by anyone and everyone—a real gift for the intelligence services. They might as well leak classified information through a megaphone while standing in a city square.
Also for information, in accordance with paragraph 4.15 of the Radio Exchange Rules of the Union of Radio Amateurs of Russia:
Amateur radio operators may, in exceptional cases and only in the event of an immediate threat to the life and health of citizens, transmit distress signals and information necessary to organize the rescue of people on radio frequencies allocated to other radio communication services.
Conclusions
Walkie-talkies are the simplest and cheapest means of communication in times of serious crisis. The cost of relatively simple, yet highly functional, analog radios is so low these days that anyone can afford one.
Don't expect the "end of the world" - walkie-talkies are very convenient in everyday life. For example, when hiking with your family or just an organized group, they will significantly increase the ease of interaction and reduce the risk of losing someone. When traveling in a group of several cars, walkie-talkies are much more convenient than mobile phones, especially since on certain sections of the roads of our vast country there may be no cellular service at all.
A walkie-talkie can be given to a child playing in a garden or dacha or in the yard. Not only is it convenient and allows communication with the child to be independent of external infrastructure, but it also provides the child with additional skills—a bonus is that it reduces smartphone addiction.
Moreover, in the event of any serious crisis, in conditions of a non-functioning or limited functioning communications infrastructure, radio stations can significantly facilitate, and in some cases, save the life of their owner.
However, the possibilities for organizing independent civilian communications are not limited to radio stations alone; there is also such an interesting technology as mesh networks, but we will talk about them another time.
Information