The spread of cellular communications does not exclude the need to use radio stations in all spheres of life, from professional activity to use in everyday life. The benefits of this type of communication are greater than it might seem.
This is the absence of a monthly fee, the ability to be in touch where there is no cellular signal, as well as a number of operational amenities. Even a child can work with the radio, but there are rules on how to use the radio. They are recommended for everyone who goes on the air.
Frequency selection
The user needs to know which frequencies can be used productively. Four types of radio frequencies are used on the air:
- (Civil);
- LPD (Unlicensed);
- PMR (Universal);
- VHF (Professional).
MW radio stations are capable of transmitting a signal over short distances, but with frequent obstacles. They are convenient in the forest, in urban areas. LPD and PMR bands operate in the frequency range from 400 to 500 MHz. This allows you to negotiate at a distance, the obstacles will not interfere. To work on LPD frequencies in the Russian Federation, it is not required to obtain a permit, the PMR range is equally legal in the West and in Russia. VHF frequencies are convenient for providing secure communications over short distances.
Checking the radio station for readiness to work
- the operation of control buttons is tested;
- checking outgoing power;
- modulation control.
To make sure that the radio station is working, it is necessary to establish communication with another subscriber with a radio device.
What you need to know about radio communication
To send a message, you need to switch to the outgoing broadcast mode by pressing the PTT button. Going on the air, you need to understand that everyone who is on the same channel with you will hear you. It is impossible to receive a signal and speak in synchronous mode.
Basic rules of communication
- First, the message must be named so that the subscribers understand who it comes from.
- After completing the message, you must confirm that it has been accepted.
- For long-term negotiations, it is recommended to use other channels so as not to occupy the general air.
How to technically organize the negotiation process correctly
- Messages should be concise, so it is recommended to think over and formulate phrases in advance.
- Check that the broadcast is not busy at the moment, and no other conversations are heard on it.
- The radio must be held upright a few centimeters from the lips. Placing the device horizontally will not adversely affect the range of the signal.
- After pressing PTT, you need to pause for two seconds, and only then speak. The message should be clear, simple and legible.
- After the end of the voice signal, the button is not released immediately, and also after a couple of seconds. This will preserve the integrity of the message, the interlocutor will not need to clarify what he heard.
- It is necessary to speak after the partner completes the replica.
Taking advantage of the advice on how to use the radio, subscribers will be able to competently use radio equipment and get the maximum benefit from properly organized communication.
Having seen walkie-talkies in a consumer electronics store, many visitors have a question, why are they needed when cell phones are almost ubiquitous? In fact, a pocket radio is a useful and necessary thing, and they have a very wide range of applications. After all, it is far from always convenient to dial the number of a specific subscriber on a cell phone or smartphone, especially when you need a dozen or two people at the same time.
If it is necessary to organize communication between a large number of subscribers (guarding a hypermarket, the movement of a convoy, hunting in a group, communication with a crane operator at a construction site, and much more), a walkie-talkie is an irreplaceable thing. In addition, the coverage of mobile operators, although it is expanding every year, still does not cover all locations. Tourists often go to places where cell phones don't work at all. And again - it is easier to use a walkie-talkie to communicate in a group. I pressed the PTT, reported the necessary information, released it, and received an answer. It's simple, no dialing, no searching for contacts in phone books, and no coverage issues. If the subscriber is within reach and keeps the walkie-talkie in standby mode, and this always happens on hikes, he will definitely answer. So, as you can see, walkie-talkies are necessary and very useful. You just need to choose the right option.
What radio stations do you need to buy
If we talk about radio stations in general, then they differ into those for which you need to obtain special permission, including the radio amateur callsign, and devices that are unlicensed and can be used immediately after purchase. Walkie-talkies, for which a permit is required, are sold in specialized stores. Consumer electronics stores mainly offer walkie-talkies that operate within the legal ranges for unlicensed use. That is, you can buy a walkie-talkie, charge its battery and start working on the air.
Three frequency bands are available for unlicensed access in Russia: CB, LPD and PMR. The CB range requires the use of fairly large equipment and, most importantly, requires rather large antennas to ensure high-quality communication. The quality of communication can be very different due to the peculiarities of the transmission of radio waves in this range. In addition, handheld CB radios do not provide stable communication quality.
LPD and PMR radios operate at closely spaced frequencies in the UHF (decimeter) range. Radio waves in this range propagate in a straight line, but at the same time there is almost no industrial interference at the frequencies, so the quality of communication within the range of the walkie-talkies remains stably high, the speech is legible and understandable. At the same time, the equipment itself is compact and lightweight.
When choosing a walkie-talkie for use, you need to pay attention to the following points:
- the frequency range in which it operates;
- number of channels;
- communication range declared by the manufacturer;
- additional functions (noise reduction system, the presence of signal coding, the screen and its information content);
- duration of autonomous work.
Frequency range and number of channels
Let's leave the CB radios for truckers and those who like to build large antennas. For most household and work purposes, the LPD and PMR range radios, which are mainly offered by modern manufacturers of communication equipment, are excellent.
These ranges, and, consequently, the walkie-talkies for working in them, have the following features:
- LPD (stands for Low Power Device). Frequency range from 433.075 to 434.775 MHz. There are 69 channels available for use. Accordingly, a walkie-talkie designed to operate in this range will have a maximum of 69 channels for operation. Usually manufacturers do this, but there are some models that have fewer channels in LPD. This is due to the peculiarities of the circuitry of specific radio stations and is done to reduce their cost. The fundamental feature of using this range is that the output power of the devices is limited to 0.01 W. Therefore, the name Low Power appeared. Accordingly, the communication range in this range will not be very long. But, on the other hand, a large number of channels allows you to always choose the best option for communication;
- PMR (acronym stands for Personal Mobile Radio). Frequencies for operation in this range are in the range from 446,000 to 446,100 MHz. Since the bandwidth is smaller, there are only 8 channels in it. Those manufacturers who claim that they offer 16 channels in PMR are a little disingenuous. In fact, there are still eight channels, and additional ones are obtained through the use of additional coding. There is simply no room for more than 8 channels in the PMR band. An important advantage of the range is the ability to use walkie-talkies with a maximum power of 0.5 W. This means that under equal conditions in terms of terrain and weather, the communication range with a PMR radio will always be longer. Therefore, it is these walkie-talkies that are most popular and most common among users.
In fact, manufacturers offer for purchase two options for radio stations: operating only in the PMR band or in the PMR and LPD band. The option with the purchase of dual-band radios looks more attractive, as it provides more opportunities for communication. High PMR power is not always needed, there are often situations when low power and long battery life in LPD are better suited for current tasks.
Separately, it should be noted walkie-talkies that cover not only the LPD and PMR bands, but the entire UHF (400 - 480 MHz) or VHF (134 - 174 MHz) bands, as well as UHF / VHF. Such radio stations can also be purchased in stores. But for their use, especially in the VHF-band, it is imperative to obtain a license, since a small band is allocated for amateurs, and these frequencies are mainly used by security officials. In turn, UHF-radios can be programmed to work only on authorized unlicensed channels. Similar walkie-talkies are produced, for example, by "Argut".
A set of walkie-talkies or a separate radio station
Walkie-talkies for communication are sold in two configuration options: two or one device. Buying a set of two radios is convenient because you get a ready-made set for communication. The disadvantage of such a kit is that it usually includes household-class devices that have a low level of protection against external influences, a relatively simple circuitry, and minimal functionality to ensure communication. 
One walkie-talkie in the delivery set is almost always a device with a reliable protected case, a good battery, a sensitive receiver, the maximum allowable power level, additional functions that allow you to provide stable communication at the largest distances for unlicensed ranges. Often one such walkie-talkie is more expensive than a set of household-class devices, but they also provide a higher quality of communication.
Communication range
Focusing on the communication range, which is indicated in the description of the walkie-talkie, you need to understand that the manufacturer reports on the characteristics measured in open areas in good weather. In reality, especially in urban areas, forests, rough terrain, it will be different.It is clear that under the same conditions a walkie-talkie for which a communication range of up to 10 km is declared will behave better than one for which the manufacturer stated that it works at a distance of up to 5 km or even up to 3 km. This is due to both the best characteristics of the receiving path, and the presence and capabilities of a noise reduction system capable of isolating the desired signal from the background of noise, as well as additional functions (coding).
Useful radio station functions
We talked about frequency ranges, power, communication range and delivery sets. Now let's take a look at the additional functions and characteristics of the radios.
It will be very useful if your radio supports the function of signal coding with CTCSS codes. If there are many stations on the air, the problem can be solved by using such coding. Turn on one of the CTCSS or DCS codes on your radios, after which the extraneous signals magically disappear from your air, since the automatic noise reduction system opens the receiver only after it recognizes the desired code. Of course, this does not mean that your conversations will be closed from listening by others. Scrambling and other protection methods are used to protect signals from unauthorized access. CTCSS and DCS codes are only for the purpose of improving communication quality.
Be sure to pay attention to the screen of the radio station. It is highly desirable that it be. Since they are made on a monochrome matrix, information is easily read from them in any conditions. It is good when the numbers informing about the frequency and channel on which the work is being carried out, as well as all special characters informing about the operation mode of the radio, are displayed in a sufficiently large and clear font, and the control buttons are pressed comfortably, with a clear, well-felt tactile response.
Another useful feature that is usually found in fairly expensive radios is VOX (voice control). If your walkie-talkie has it, then when you connect a special headset, you do not need to use the PTT, the transmitter will turn on automatically when you speak into the microphone.
It is also useful to be able to switch the transmitter power to high and low power modes. In this case, you can choose what is more important to you - the communication range at the limit of the radio's capabilities or the time of its autonomous operation. After all, the lower the output power of the transmitter, the longer the battery will work without recharging.
Be sure to pay attention to the battery life. Everything is simple here: the more this value is, the better. Of course, the larger the battery capacity, the higher the mass of the radio. But if you are planning a trip to places far from settlements, autonomy is very important. On average, compact walkie-talkies are capable of working in a talk mode from 8 to 20 hours. In real conditions of use, this allows them to be used without recharging for several days. Please note that some walkie-talkies allow the use of AA or AAA batteries, while others operate only on a battery, and even of an original design.
The summary will be as follows. Despite the development of cellular communications, walkie-talkies cannot be written off. This is a very useful, and in many cases irreplaceable and very convenient equipment. Especially if you choose the option that suits your tasks.
PS: There is not a single word in this article " Adjacent"
. Connection Is one of the most important elements in working in the navy. It is divided into external and internal... Let's talk about this today internal communication as communication between crew members by means of portable handheld VHF radio stations, which are also called - walkie talkie(walkie-talkie).
It would seem that there is nothing difficult in simply pressing the communication button and transmitting a message, but a couple of tips for the competent use of ship VHF will significantly facilitate the work of the navigator and the sailor and improve the communication system.
1. Press the button, then talk!
A common mistake among young sailors. Pressing tangent(button or key for switching from reception to transmission on the intercom) wait literally a second, then send your message. Switching from reception to transmission requires a little, but still time. When you press a key and start speaking at the same time, the first words of the message are eaten up, and only a fragment of the phrase “reaches” your opponent.
2. Don't turn up the volume at full!
The principle of operation of the speaker is an electromagnetic field that vibrates the membrane, creating sound. The quality of the membranes of the average walkie-talkies that we have on the ship is far from the best quality. Too much electromagnetic field can rip up the diaphragm and cause the speaker to wheeze. The playback quality will decrease significantly and you will find it difficult to make out the words. Set the sound volume slightly above average and you will get cleaner sound.
3. Hide from the wind!
The directed air flow to the microphone of our walkie-talkie creates vibrations that affect the quality of information transmission. You are standing on the bow of a ship, a strong wind is blowing, walkie-talkie is not covered by anything, you report to the captain the distance to the airlock wall. The captain hears only crackle and words that cannot be made out. In this case, cover the radio with a jacket, go behind any object from the leeward side, bend over and hide behind the bulwark.
6. Call your interlocutor!
On one channel VHF walkie-talkies there can be a sufficient number of crew members on duty, therefore, before starting to transmit your message, call the person to whom it will be addressed. For example, the third mate wants to call the captain and report to him about the arrival of the ship's agent. It is best if the navigator starts communication with the words “ The captain is the third", After which the captain will most likely answer -" In touch" or " Speak", or " The captain is listening" (in English Go ahead). Once you have established contact, you can begin transmitting information.
5. Repeat an important message!
In radio communications in the fleet, they are taught to repeat received messages, so that the other operator is convinced of correct receiving the sent message. Of course, you should not repeat everything that you are told and literally echo all the interlocutors. Highlight important parts of the received, as well as numbers and values. For example, if you are a sailor on duty on the deck of a tanker, the chief officer asks you to open the expander of the second right tank:
- AB Chief!
- I'm listening!
- While there is time, please open the expander of the second right tank, the surveyor will conduct an inspection.
- Accepted, open the expander of the second right.
6. Don't say too much!
In fact, it is rare for shipborne operations to take a long time to broadcast. There is for everything, and the answer to them, as a rule, requires only approval or denial. When you want to convey your message, you should not start philosophical conversations about the creation of the world. Briefly and capaciously, convey the message in clear words and concepts, do not jabber, do not drag your uh-uh between phrases, do not hang around. First think about what you want to say, then speak. Believe me, listening to a long and painful birth of a thought is annoying.
7. Don't interrupt!
Very often, inexperienced sailors begin to transmit something without waiting for the opponent's message to end. As a result, neither one nor the other receives full information. Make sure the other person has finished their message, then reply. In good execution, after each message, one should say “ Reception" or " Over“, But in practice these words are rarely used.
8. Attach the walkie-talkie!
The author of these lines has seen more than once how sailors lost their radios, dropped and broke them, drowned them in the sea. A young officer goes to mooring, pretending to hold the radio in his hand, there is a situation when he needed to help pull the mooring line, he puts the radio in his breast pocket, then he wanted to look overboard, outweighs, and the radio flies into the water, staying there forever. If our hero was not ashamed and took a holster for a walkie-talkie, fixed it on the body, then, most likely, I would have avoided the problem. However, the talent of some to drop items into cargo tanks is incorrigible, and nothing can be done about it.
The great navigator Jacques Yves Cousteau communicates on the ship's radio
9. Turned on - check the connection!
Including its walkie-talkie check the connection. Perhaps, during your vacation, the watchmen switched to another channel, and you still have an old one. And just a walkie-talkie, like any equipment, may not turn on or give an error. Get off at the mooring, turn on the radio, say “ Bridge - 3rd Officer, Radio check!", What you will be answered" Loud and Clear“. We made sure that we are in touch.
10. Watch your walkie-talkie!
Have enough battery charge very important. Your walkie-talkie has been in operation for 4 hours, you go to clean the tank, going downstairs, you begin to hear the treacherous squeak of the low battery alarm. If you changed the battery in advance, you would not waste time and energy. By inserting a new battery, put the old one on charge. There is always one battery in the radio, one in the charging station! Take care of the radio, do not drop, do not use it for other purposes. New ones will not be brought soon, but it is necessary to work with something.
When ordering a walkie-talkie to work on your ship, remember that the most simple walkie-talkies will be the most demanded... To keep the crew connected internally, we don't need GPS, an address book, and other useless things that drain battery power, not to mention that it's a waste of money. Those who work on tankers remember that walkie talkie must be explosion-proof and have the corresponding manufactory certificate. Also, by purchasing equipment from another manufacturer, you risk that channel frequencies may differ, and the walkie-talkies simply “will not hear” each other. 
Very popular with people working at sea, portable stations Motorola series GP... They are simple, reliable, and relatively inexpensive.
We hope the article turned out to be useful for workers of maritime transport and will help in the first days of work on the ship. Speak clearly, don't shout, use the correct language. Going to the navigational watch on the ship's bridge, take the radio with you, if you need it, but there is no spare radio on the bridge.
Despite the weather disasters, this year's summer nevertheless came into its own, and many easy-going motorists rushed to long-distance routes - some to the south, and some to more curious and remote corners of immense Russia. In the midst of the travel period, car owners traditionally have a growing interest in CBC radio stations operating on the "truckers channel" that can be useful on long-distance travel. For those wishing to purchase and install a walkie-talkie on their own - our instruction!
Connecting the radio to power
The following guide on installing the C-Bi-radio in a car is not for those who use radio communication daily and professionally, but for those who need it for occasional use, mainly on long trips. In this case, most drivers will prefer not to fix the radio stationary in the cabin, spoiling the interior and provoking parking thieves, but will want to attach it temporarily in a suitable place: between the seats, between the seat and the side pillar, or in the tray for small things under the dashboard, as is done, for example, in the photo Chevrolet Lachetti:
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Attached a walkie-talkie - we connect power to it! There is an opinion that the radio station in the car must certainly be connected with a separate wiring from the battery, but this solution is more suitable for daily use. In our case of occasional use, this is absolutely unnecessary - it is much more convenient to take power from the cigarette lighter socket. This is the simplest, fastest, and at the same time, we should emphasize, quite correct connection. Not a slapdash compromise, as some think, but one that meets all the requirements - both in terms of the power unit and in terms of the direct operation of the radio station on the air.
Such a connection is absolutely safe for wiring and is carried out in half an hour. And most importantly, it is optimal in the case of a new car and harmful warranties, who are only looking for an excuse to refuse a guarantee for far-fetched reasons.
For a radio station with an output power of 4-5 watts, the maximum current consumption does not exceed 2-3 amperes, and for a radio station with a power of 8-10 watts - less than 5 amperes, which is at least two to three times less than the current of the fuse protecting the cigarette lighter socket.
To connect the walkie-talkie to the cigarette lighter, we extend the two power wires coming out of the radio station - black and red - by soldering or twisting to a length of 1-2 meters (depending on the intended place of installation of the device). At the end of the added wire we solder (center - plus, side contacts - minus) a standard male connector into the cigarette lighter, which is sold in every auto shop.
the power cord plug of the walkie-talkie should be inserted exactly into the cigarette lighter in the dashboard, using splitters, the quality of which is often disgusting, is undesirable!
If there is only one cigarette lighter socket, and you need to power the phone, the recorder, and other gadgets on the road, and the warranty period has already ended, and your skillful hands are not afraid of the need to drag the wire from the engine compartment into the passenger compartment, then you can connect the radio station directly to the battery. Although once again I will note in parentheses: such a connection does not have any advantages over powering through a cigarette lighter - neither from the point of view of electrical safety, nor from the point of view of communication quality.
In this case, you will have to buy a three-meter (approximately) piece of an ordinary power supply wire with a cross-section of 2x1.5 mm, pack it along its entire length in a plastic corrugation and drag it from the battery into the passenger compartment through some kind of rubber seal on the motor shield. Terminals for M6 bolts and a 10 ampere fuse are crimped or soldered to the ends of the wires near the battery (the fuse is placed in the positive wire next to the battery), and the radio power supply "tail" is connected to the two opposite ends of the wires, observing the polarity. The junction of the wires is carefully insulated with adhesive tape or heat shrink.
Antenna installation
The station is installed and connected, now we mount the antenna. We will assume that it is quick-detachable with a magnetic sole, which does not require spoiling the body for installation.
Therefore, we will give only a few general theses - without delving into unnecessary theory.
- Antennas with a length of about a meter or even less are efficient, but extremely ineffective. The dependence of efficiency on length is straightforward; when buying, you should prefer an antenna with a length close to two meters. However, as the length increases, so does the price ...
- The optimal installation of the antenna is on the roof (in the center or on the edge - there is practically no difference). Somewhat worse - on the trunk, but also quite acceptable. In order not to spoil the paint on the roof, put polyethylene under the magnet.
- The wire from the antenna to the station is passed between the door seal and the door opening or between the trunk lid and the trunk opening seal and is fed into the passenger compartment. Make sure that the seals do not leave visible dents on the cable!
- The antenna cable with a magnetic base cannot be arbitrarily shortened or lengthened - its length should remain unchanged, about 3.6 m. We hide the excess under the seats or rugs, without twisting into rings or coils.
- And now the most important thing: the antennas in the store are sold unconfigured, since the tuning depends on the installation location on a particular car. Most often, the adjustment is carried out by changing the length of the antenna pin (pushing in and out), for which a small hex key is included in the kit. The place of adjustment will definitely be indicated in the instructions for the antenna.
Antenna tuning
Actually, antenna tuning is the most important moment in our entire history. Perhaps the customization should be ordered by professionals: these services are inexpensive, the work takes less than half an hour and is offered in truck parking lots and near major auto dealerships on the highways. But many people prefer to figure out the issue on their own, adhere to the principle "if you want to do well, do it yourself!" and want to have their own set of tools to monitor the condition of the antenna in the future. For them - the following master class. Again: only an algorithm, without delving into unnecessary theory and physics of the processes taking place, into which everyone, if desired, can plunge into independently.
To tune the antenna, we need a device called a SWR meter (standing wave ratio meter), which is easy to get - Google for help. The cost of the simplest model is from 500 to 1000 rubles. The most common device, which has been on sale for many years under different names (SWR-420, 430, KW-520, etc.), is actually the same Chinese SWR meter with the same operating principle. and the same designation of switches and connectors. The device, of course, is more than average, but for infrequent use it will do just fine.
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We also need a high-frequency connector of the same standard as the jack on the radio and the plug on the cable. It is needed to turn on the SWR meter between the radio station and the antenna, without significantly lengthening the antenna cable. A male-to-male barrel adapter (for hard connection) or a short (10-20 cm) antenna cable, also with male connectors at both ends, is suitable. The connector standard is best known as "PL", which is how you ask for it in a store.
RTX, plug the antenna into the SWR meter connector marked as ANT.
(if the connectors of the SWR meter are not labeled, insert whatever you like - the SWR meter is, in principle, a symmetrical instrument)
And that is all. As you can see, this is not so difficult. But now on the way you can have fun listening to the conversations of "long-range", sometimes useful, sometimes - not very much. And do not forget that children for whom it is too early to listen to these conversations may go with you in the car.
Using a smartphone as a walkie-talkie is not a step backward in terms of technical progress, it is a great way to save money on buying a walkie-talkie, and simply combine two devices in one. Today we will talk about how to set up your gadget and make a full-fledged walkie-talkie out of it.
Zello walkie talkie
One of the most popular ways is to install the Zello app. This application has gained popularity due to its ease of use and the fact that the application is completely free. There is, however, a paid version, but it was not possible to determine its differences and advantages.
This program can be installed both on a mobile phone and on a computer or laptop. Zello will delight you with a fairly convenient menu with various options. For example, you can save and play message history, create password-protected channels. The program also displays the online statuses of contacts, which is very convenient.
Zello supports up to 800 connected interlocutors simultaneously. True, with such a number of people, the quality of the transmission will suffer significantly. For comfortable communication, the number of contacts should not exceed 300. Naturally, you need to have an Internet connection to use it.
It is very convenient that this application supports bluetooth headsets, so it is very convenient to use such a walkie-talkie while driving or in the office.
The second most popular app after Zello.
Quite an interesting and handy application that turns your phone into a portable walkie-talkie. It has many additional functions, for example, the ability to transmit not only voice messages, but also other content: photo, video, audio, text.
In Voxer, you can indicate your location. This function is useful for travelers, as well as people who are in unfamiliar areas. In addition, Voxer allows you to save your message history. There is also a very convenient function that allows you to record an audio message even without Internet access: you can send it when the opportunity arises.
One of the most interesting features of Voxer is the ability to play voice messages at two or three times the speed.
Mobile walkie-talkie from the operator
This option is suitable for those whose mobile phones do not support these applications. The phone model does not matter, because this is not a separate application, but an operator's service. It should be noted that not all Ukrainian mobile operators support this function.
To use a mobile radio from Kyivstar, you need to register the settings that the operator will send you and pay a monthly fee for using the service.
The radio from Kyivstar allows you to create both public and private channels. A significant difference from third-party programs is that the mobile radio does not require access to the Internet. But it is worth noting that it works only within the coverage of the mobile operator's network.
Walkietooth
Walkietooth uses Bluetooth technology to transmit voice messages. The program is not popular, as the Bluetooth technology is already outdated and has several significant drawbacks.
For example, the application allows you to connect no more than two phones with each other and only at a very limited distance (about 10 meters between devices). In addition, the duration of voice messages is no more than 10 seconds.
But don't discount this app. Walkietooth can be very useful in some cases: for example, when you need to communicate underground, as well as in conditions of poor visibility or communication.
Push-To-Talk
The famous Push-To-Talk feature that many smartphones have (especially Nokia and Motorola). This technology is still improving, despite the existence of the improved applications that we talked about earlier.
The response time for Push-To-Talk is approximately 1-1.5 seconds, and the distance of voice message transmission is limited by the operator's network.
Among the significant disadvantages of this function: an outdated and rather rare operating system that runs Push-To-Talk, namely Symbian. Every year it loses its relevance more and more.
