The range of the radio depends on:
1. From the power of the transmitters. Increasing power increases range. Power also depends on the state of charge of the battery, the maximum power is reached when the battery is fully charged.
2. Sensitivity of receivers. (the newer the models, the better the combination of characteristics)
3. Working frequency. At higher frequencies, the performance of small antennas is higher. But a higher frequency passes through obstacles worse (walls, buildings, trees). Best range for work portable radios in difficult conditions 430-440 MHz.
4. From the length of the antennas. Longer antennas have better gain, which results in better receiver sensitivity and greater transmitter efficiency. Any antenna is configured (coordinated) at the factory, self-made lengthening or shortening of antennas is unacceptable! It is unacceptable to use TV antennas, cables, connectors, they are not compatible in terms of impedance. In walkie-talkies 50 ohms. In TV 75 Ohm.
5. The presence of interference sources in the operating range.
6. Antenna height(walkie-talkies). That is, the connection from the last floor of the building will be much further than from the first.
For example: 8-watt walkie-talkie in the range of 400-470 MHz. in the city from roof to roof will hit up to 100 km. and from basement to basement up to 100 meters.
7. For all portable radios, the efficiency (matching) of the antennas is highly dependent on the position of the radio. According to test results, the best performance when the radio is held in the hand, the antenna away from you(from the head), the antenna and part of the arm from the radio to the elbow lie on the same straight line. The worst performance is when the antenna is pressed (close) to the arm, head, body. Reception and transmission will be essential it is better if the radio antennas are parallel to each other and if the antennas are perpendicular, the connection will be worse.
There are many factors affecting the range, so it is practically impossible to accurately predict what the real range of a radio station will be in a particular place.
The declared range of the radio station implies the operation of radio stations in the line of sight without sources of interference on the way.
At what range will powerful portable radio stations work in the forest?
What is the guaranteed range of the radio in the forest?
Almost every hunter asks us this question. Everyone who has already encountered the use of walkie-talkies or long-range radiotelephones knows that the range of radio communication is very dependent on terrain and conditions.
For example, a FOREST happens: Coniferous on a plain, without undergrowth, in such a forest the communication range of 6-8 watt walkie-talkies will be up to 7-10 km. Depending on the density and moisture content of the forest.
Deciduous or mixed forest with dense undergrowth, the most difficult forest for radio communication. Usually in such a forest, the communication range does not exceed 5-7 km.
It worsens communication conditions even more if the forest is with hills and ravines. Connections between different ravines (from ravine to another ravine) located 1 km. may no longer be. At the same time, the connection from a hill to another hill can reach 20-30 km. Communication from the hill to the ravine can reach 7-10 km. Along a straight river up to 10 km. On the open water of the lakes, this is all direct visibility, up to 30 km.
For walkie-talkies with less power, the range in the forest will be significantly less. The range examples given are the maximum for the most powerful and long-range portable radios 6-8 watts 400-470 MHz.
If you are not satisfied with such a communication range in the forest, you need to choose military-style walkie-talkies, the size and weight of a car battery and an antenna the length of a fishing rod. Only such walkie-talkies can provide a long communication range in forest conditions.
What is the communication range of the walkie-talkies on the highway (on the highway)?
For communication between cars, it is best to use stationary car radios with external antennas with a power of at least 8 watts. These walkie-talkies will be able to provide stable radio communication for tens of kilometers.
If you still decide to use portable radios with a power of 6-8 watts, the communication range will greatly depend on many factors and fluctuate from 2 km to 20 km.
The main factors that significantly affect the communication range of radios on the highway:
- Vehicle equipment. Glasses tinted with metallized film, glass heating, glazing area. All these factors take a significant part of the radiation from the radio antenna, reducing the communication range.
- Height of landing in the car. The higher your cars are, the further the connection will be. The difference between two low sedans and high jeeps can be as high as 20-30%.
- Route locations. If communication occurs from mountain to mountain, then the range can reach 20 kilometers. If the mountain is between the cars, then the range can be reduced to 1 km. On straight sections, the range will be up to 5 times greater than on sections winding in the forest or between mountains.
- Route congestion. The more cars on the highway, the worse the connection, the shorter the range. High trucks, buses, KAMAZ trucks create a natural barrier to radio waves, absorbing them or reflecting them in the opposite direction. Almost all cars have electronic means inside (cell phones, navigators, computers ..) that emit small interference, with a large accumulation of cars on the communication line, this interference becomes significant.
In addition to these factors, there are many more factors affecting the communication range of walkie-talkies. There can be a high mountain on the side of the route and the signal can be reflected from it, increasing the communication range at times, despite other factors. Rainy and humid weather greatly impairs communication, wet car windows absorb radio radiation more strongly, reducing the communication range.
Even under the worst conditions, powerful portable radios (7-8 watts) provide a communication range between cars of 1-2 km. Usually this is enough if you are traveling in a group of cars.
*Use external car antennas together with walkie-talkies, we do not recommend. The wire from the external antenna quickly fails due to frequent kinks, which leads to the burnout of the radio transmitter.
Radio power and range
Which band is best for portable radios
In the range CB (27 MHz)"long waves" of radio waves can be reflected from the ionosphere (sky), bend around the earth and spread over thousands of kilometers. But this requires a very large transmitter power (more than 100 watts) and very huge antennas.
In a portable version with low power and short antennas, walkie-talkies in this range work very poorly, since small antennas cannot effectively radiate and receive long radio waves. And there is not enough power for the reflected signal to reach the ground back. This range is only good for powerful fixed radios with large antennas.
This range is popular among truckers, powerful stationary car radios and external antennas about 2 meters long are used.
VHF (136-174 MHz) the wavelength is not short enough to radiate and receive well on short portable antennas. But it has good penetrating power. Works well in car radios with external antennas on the car roof. Or in walkie-talkies like "backpack". According to customer reviews, in some cases, walkie-talkies of this range work better in the forest. Sometimes (informally) this range is referred to as the "Forest Range".
UHF (400-480 MHz) this is the optimal range for walkie-talkies. The wavelength is short and very efficiently transmitted and received on short antennas. While maintaining a fairly good penetrating ability through the forest, houses ...
All major license-free communication standards are located in this range. LPD, FRS, PMR. Walkie-talkies of this range are the most long-range.
Attention! It is forbidden to use frequencies higher than (greater than) 480 MHz in cities, as it interferes with digital television.
DPMR- This is a modern digital modulation standard (data transmission by means of electromagnetic radiation). New digital modulation capabilities provide higher effective transmit power and higher receive efficiency. Reliable confidentiality of negotiations is ensured due to the possibility of digital encryption with a key of 65536 combinations. Pure and clear sound (digital sound quality). Possibility of individual and group calls of subscribers and many other possibilities.
More details can be found in the official technical documentation for the protocol.
Access method: FDMA
Modulations: Four-level FSK
Baud rate: 4800 bps
900 MHz. The wavelength in this range is very short, which makes it possible to use very small antennas. But the waves of this range pass very poorly through obstacles, such as the walls of houses, forests, hills. Communication range can only be obtained in line-of-sight conditions.
Now you should not buy outdated walkie-talkies with one range, new models of two-band walkie-talkies are now the same. If you do not have the opportunity to buy a two-band portable radio station, we recommend buying powerful walkie-talkies in the UHF 400-520 MHz range. Even if under some conditions the VHF band (136-174 MHz.) gives a greater communication range in the forest, then it is very insignificant. But in all other communication conditions (fields, highways, cities, mountains) it loses significantly UHF band 400-520 MHz. All unlicensed frequencies are in the UHF 430-450 MHz range.
What are the benefits of a DPMR or DMR digital walkie-talkie?
Firstly, it gives only advantages, since digital walkie-talkies can operate in the usual analog mode and they have all the features of conventional walkie-talkies.
Main advantage digital communication is that you do not need to use callsigns to communicate within a large group. You can call specific callers in a group without disturbing others. In analog walkie-talkies, the call is heard by the whole group and you must say phrases like “first to fifth ..”, “fifth accepted”. Each subscriber is forced to listen to all the conversations of the group, suddenly they say his number or call sign. In numbers, all this is not necessary! Moreover, the digital has features that allow you to immediately see whether the remote radio is receiving your signal or not.
You can see the numbers or names of the callers who are calling you (not in DM-5R) .
You get high-quality digital sound without noise.
Safety! Your conversations cannot be heard from other walkie-talkies (if the encryption function is enabled).
These are only the main advantages of digital communication, you can find more details about the functions and capabilities of digital walkie-talkies on the detailed description pages (model cards).
Channel frequencies LPD range:
LPD mesh:
Channel 1 = 433.075 further step +.025 channel and so on up to 434.775 (69 channels)
Mesh FRS Channel Frequencies:
1 462.5625
2 462.5875
3 462.6125
4 462.6375
5 462.6625
6 462.6875
7 462.7125
8 467.5625
9 467.5875
10 467.6125
11 467.6375
12 467.6625
13 467.6875
14 467.7125
Table of PMR channel frequencies
Channel Frequency (MHz) To enter the frequency, you must set the frequency grid step 6.25
PMR-1 446.00625
PMR-2 446.01875
PMR-3 446.03125
PMR-4 446.04375
PMR-5 446.05625
PMR-6 446.06875
PMR-7 446.08125
PMR-8 446.09375
Walkie Talkie Compatibility
Often buyers of walkie-talkies ask: which model of walkie-talkie is best compatible with other models.
High-quality models of walkie-talkies always comply with established communication standards. Frequency tuning, modulation level, receiver channel width and other characteristics are made and adjusted in accordance with the requirements of the standard. All models of high-quality walkie-talkies are well compatible with each other. Walkie-talkies are of low quality, cheap analogues of popular models, stripped-down versions, often do not meet the standards, and work tolerably only among themselves. When communicating with other models of walkie-talkies, the communication will be of very poor quality (quiet sound, poor intelligibility, wheezing, noises). That is, there are no such walkie-talkies that will be perfectly compatible with any low-quality models. We check the characteristics of all walkie-talkies for compliance with standards, we do not sell models that have significant deviations from the standards.
What are CTCSS and QT/DQT subtones for?
Some channels (frequencies) may have a programmed (tuned) CTCSS or DCS subtone. A subtone is a subsonic signal that allows you to ignore the conversations of other walkie-talkie users who are using the same channel (frequency). Allows you to ignore any man-made interference and noise. When you receive a signal that has a different subtone than your radio, you will not hear that signal. Likewise, the signals that you transmit will only be heard by subscribers whose subtone matches the one set in your radio.
CTCSS is a constant tone that is added to the transmitted audio. If CTCSS = 67.0 this means that a constant tone of 67 hertz is added to the sound. It is not audible thanks to special subtone filters.
QT / DQT - more modern, an identification code is transmitted at subsonic frequencies.
Comment:
Using channels with subtones set frees you from unwanted interrogations and noise, but this does not mean that your conversations will be confidential. To protect against listening, you need to buy walkie-talkies with the Scrambler function or digital walkie-talkies.
What is SWR or SWR?
SWR (SWR) - Standing Wave Ratio. All high-frequency devices, cables, connectors, antennas, amplifiers are produced for standard wave impedance. This characteristic impedance is the main indicator of compatibility. All radios and extras equipment for them is produced for a wave impedance of 50 ohms. TVs and extras equipment for them (cables, connectors, antennas) are produced with a wave impedance of 75 ohms. Therefore, TV cables and antennas operate in the same frequency ranges as walkie-talkies, BUT THEY ARE INCOMPATIBLE in terms of impedance.
SWR is measured across any high-frequency circuit and shows the accuracy of compatibility. If the SWR is poor, then most of the signal is reflected back and released as heat. All modern radios have a built-in SWR meter. It monitors the SWR of the antenna during transmission and if the SWR is bad, it lowers (limits) the power of the transmitter. This is done so that a powerful radio transmitter does not burn out if the antenna is leaned against metal, against a hand, or the radio is held incorrectly. That is why it is so important to hold the walkie-talkie correctly in your hand in order to achieve maximum range. (see first paragraph)
What determines the operating time of the radio?
The operating time of the radio depends on:
1. From the capacity of the battery. The larger the capacity (mAh), the longer the radio will work.
2. From the frequency of using the transmission (PTT button). When a powerful transmitter is running, the station consumes battery power to the maximum. If the radio has several transmitter power modes, then when using low power, the radio will work longer but with a shorter range.
3. Availability of battery saving functions. The mode when the receiver of the station works periodically turning on, for short periods of time. In this mode, the turn-on time of the station is slightly slowed down when it is called.
! If the battery is worn out, its capacity is much less than that of a new one.
! Deep discharge of the battery will drastically shorten its life. When the radio is left on after the battery is completely discharged.
What types of batteries are there and how do they differ?
1. NI-Cd Nickel Cadmium - The most inexpensive type. They have a memory effect, it is necessary to observe the charge-discharge cycle.
2. NI-Mh Nickel Metal Hybrid - No memory effect, high capacity for the same size.
3. Li-ion Lithium - Light, quickly charged, afraid of severe frosts. The lithium battery always has an electronic circuit inside to ensure charge control, temperature and other parameters.
What is a repeater?
Repeaters significantly increase the range of radios. If the repeater is installed at a high point (for example, on the building of Moscow State University), then the communication range between the radios will be up to 60 km. in the town.
A repeater is a receiver and a transmitter that operate on different frequencies. The receiver receives the signal, and the transmitter immediately transmits it on a different frequency with high power and to a good antenna.
In order for the radio to work through a repeater, it must have transmit and receive frequency separation function.
You can find information about amateur radio repeaters in your city on the Internet, through search engines.
Communication R-12 is a full-fledged amateur radio station, with a full-size keyboard that allows direct frequency entry, with the ability to scan the radio in the range of 400-470 MHz, (normal, priority, dual), with support for subtones - CTCSS / DSC, with the ability to scan subtones, with the possibility of memorizing 108 channels, etc.
In a word, this is a serious radio station that will suit those who need a small, lightweight walkie-talkie that can easily fit in your pocket and will not interfere, but it will work perfectly.
The R-12 model is a walkie-talkie for skiers, motorcyclists and cyclists, it is well suited for paintball, for a security guard and for many other purposes. It should also be noted that this radio station is made in a durable case, on an aluminum chassis, and it is not at all easy to break it. The top mechanical switch makes it easy to adjust the functions of the walkie-talkie, while the buttons are very small, this feature is very useful. Voice control control, in this case, will be very useful, because sometimes with such a small size you will not get into the right button with your finger.
Well, the price of this radio. Cheaper just for free. The closest analogues of the Svyaz R-12 model are the Yaesu VX-2R and Yaesu VX-3R radio stations.
Comparative characteristics of radios can be seen below.
File with LPD/PMR frequencies for radio Communication R-12
For the convenience of programming the R-12 station, we have prepared a file in which the most common frequencies are already loaded - LPD (69 channels 433-434 MHz) and PMR (8 channels 446-447 MHz), which you can download, open in the program "upload into the walkie-talkie", without suffering, stuffing them.
Comparison of the operation of the R-12 radio station with some popular radio stations:
If we compare the work of walkie-talkies Yaesu VX-2R and Yaesu VX-3R and Communication P-12, it should be noted that the power Yaesu VX-2R and Yaesu VX-3R in the frequency range 400-470 MHz., is 1 W when powered by battery, and 2 W with an external power supply. Power Communications R-12 in the same range, set to maximum power - 2.5W when powered by battery.
You can charge Communication R-12 from electrical network and from the USB port of the computer.
Included Yaesu VX-2R and Yaesu VX-3R Lithium ion battery comes 3.7V / 1000mAh. Included Communication R-12 Lithium ion battery comes 3.7 V / 1300 mAh.
Batteries from some models are suitable for R-12 mobile phones Nokia which are not very expensive.
Comparison of radio dimensions:
Communication R-12:
The height of the radio is 80 mm, on the top mechanical switch - 88 mm, the height of the antenna - 80 mm.
Width - 48 mm.
Thickness - 24 mm.
R-12 weight - 190 g (with battery and antenna)
Yaesu VX-3R- 81x47x23 mm Weight - 130 gr.
Comparative results of testing radio stations Svyaz R-12 and R-34
Communication radio station P-34U is a standard semi-professional radio with a transmitter power of 4 watts.
When testing the real communication range of these radios, the Svyaz R-34U model showed a range not much greater than Svyaz R-12. Recall that the communication range is determined by a set of characteristics, in which the power of the radio transmitter is a parameter of the 4th level of importance. The first 3 parameters are sensitivity, selectivity, modulation quality.
The P-12 model has a very high-quality signal modulation, due to which a significant communication range is achieved.
The main functions of the radio Communication R-12:
- Ultra compact
- Rugged construction based on aluminum chassis
- Frequency range: 400-470MHz
- 108 channels
- CTCSS/DCS
- Receiving FM radio stations (25 stations)
- Computer Programming
- Manual entry of frequency and parameters
- Channel number or frequency display
- Output power: 2W
- Frequency spacing (for work with a repeater)
- Battery saving function
- Charging from a computer USB port
- VOX function
- Scan Functions (Normal, Priority, Dual)
- Scanning CTCSS/DSC codes
- Channel bandwidth selection 12.5/25 kHz
The radio has keypad lock function, you can set the keypad lock to automatically turn on.
IT'S IMPORTANT TO KNOW.
How the radio channels are set up Communication P12.
For ease of use, we supply the P12 radio pre-programmed to standard civilian LPD/PMR channels.
The first 69 channels are the standard channels LPD.
Channels 71 to 78 are standard 8 channels PMR.
If you have walkie-talkies like the Midland, which are sold in sets of 2, you can link these walkie-talkies to each other by simply setting the same channels under the same number.
Also, if you are using civilian PMR radios, such as Motorola radios that are sold in sets of 2, you can also link them together.
The channels of the Motorola walkie-talkies will match accordingly - the 71st channel on the P12 walkie-talkie with the 1st channel on Motorola, the 72nd channel of P12 with the 2nd channel on Motorola, the 73rd with the 3rd, etc., all 78 channels of P12 correspond to 8 channels of PMR on Motorola.
Also, on civilian walkie-talkies, in addition to the channel, subchannels can be installed on each channel. Subchannels are called CTCSS/DCS subtones.
All of these subtones can also be set to P12.
Even more.
How to do it: you need to look at the instructions that are posted on this page.
For ease of use, in addition to standard LPD / PMR channels, channels from 80 to 88 are programmed within the license-free frequency range, but we put non-standard channels on them, with CTCSS / DCS subtones.
In Moscow and other large cities, it is often almost impossible to find a free channel among standard channels. The air is densely occupied by a large number of subscribers, and the standard channels, let me remind you, are only 69 + 8 = 77. Total! For such a huge number of users as in Moscow or St. Petersburg or another big city.
Therefore, if you have a P12 communication radio, and you do not need to communicate with subscribers using LPD / PMR radios, it is better to immediately select channel from 80 to 88, and, with a high probability, you can hope that you will receive a clear, interference-free communication channel.
For a complete understanding, below are the frequencies programmed on the communication P12 radio.
Channel Frequency (MHz) Channel Frequency (MHz) Channel Frequency (MHz)
1 433.075 31 433.825 61 434.575
2 433.100 32 433.850 62 434.600
3 433.125 33 433.875 63 434.625
4 433.150 34 433.900 64 434.650
5 433.175 35 433.925 65 434.675
6 433.200 36 433.950 66 434.700
7 433.225 37 433.975 67 434.725
8 433.250 38 434.000 68 434.750
9 433.275 39 434.025 69 434.775
10 433.300 40 434.050 70 not available
11 433.325 41 434.075 71 446.00625
12 433.350 42 434.100 72 446.01875
13 433.375 43 434.125 73 446.03125
14 433.400 44 434.150 74 446.04375
15 433.425 45 434.175 75 446.05625
16 433.450 46 434.200 76 446.06875
17 433.475 47 434.225 77 446.08125
18 433.500 48 434.250 78 446.09375
19 433.525 49 434.275 79 missing
20 433.550 50 434.300 80 435,15500 67.0
21 433.575 51 434.325 81 435.17000 67.0
22 433.600 52 434.350 82 435.19000 67.0
23 433.625 53 434.375 83 435.21000 67.0
24 433.650 54 434.400 84 435.23000 67.0
25 433.675 55 434.425 85 435.27000 67.0
26 433.700 56 434.450 86 435.33000 67.0
27 433.725 57 434.475 87 435.35500 67.0
28 433.750 58 434.500 88 435.55500 67.0
29 433.775 59 434.525
30 433.800 60 434.550
Radio ranges and frequencies
In this article, we will briefly consider which frequencies are allocated for radio communications and which radio stations and which range should be considered when choosing equipment in a particular case. The article is presented in a free form, using simplifications in some concepts and details. It does not claim to be encyclopedic accuracy, but it will give a general idea of the frequencies used in Russia and the radio communication equipment used.
Consider, What bands do radios work on? and why, in one case or another, different radio frequency ranges.
Shortwave range - 1-30 MHz
HF radio It is mainly used by the military, the Ministry of Emergency Situations, the Navy, forestry and environmental organizations for professional communication over long distances - from 150 to 8000 km.
The main disadvantages of the HF band are low noise immunity and the need to use overall antennas up to several tens of meters long. Pluses - absolute autonomy, long communication range and low cost compared to satellite communications.
Main equipment used: Icom, IC-M802., Vertex VX-1700, VX-1400, VX-1200/1210., Kenwood TK-90, Cordon R-12, Q-Mac HF 90M, Barrett PRC-2090, PRC- 2091, Karat, Angara.
Also, within 1-30 MHz, there are 9 sections of frequencies allocated for communication to radio amateurs. The main used HF amateur radio equipment is Kenwood, Icom, Yaesu, Elecraft transceivers. If for professional stable radio communications, the range is usually limited to 8000 km, then radio amateurs often conduct transcontinental radio sessions with their colleagues located on the other side of the globe.
Currently, the market for software-implemented radio - SDR equipment is gaining momentum. Software-based radio is beginning to be widely used in amateur radio, military and commercial applications. To date, Harris and Alcatel Lucent have already implemented several successful projects that use equipment based on SDR technology and cognitive radio (a radio system that can receive information about the features of its own operation and, based on this data, adjust its operating parameters). In the future, SDR technology has every chance of becoming a new standard in the telecommunications market.
Civil band - 27MHz
Conditionally called "range 27 MHz". Frequency range 25.6-30.1 MHz (officially allowed section - 26.965-27.860 MHz). Another name is CB range from the English abbreviation CB - Citizen Band.
Range of truckers on walkie-talkie this is the 15th channel, at 27.135 MHz, in amplitude modulation (AM) mode. The channel is actively used by truckers for communication on the highways. in big cities, walkie-talkie cb range 27 MHz, used by motorists to exchange traffic information. In different cities, different channels are used for urban communication. For example, in Krasnoyarsk it is channel 40, with a frequency of 27.405 MHz, in Kemerovo it is channel 27, with a frequency of 27.275 MHz. At the frequencies of urban auto channels, frequency modulation (FM) is used.
Also, radio stations of this range are used by small taxi firms and cargo carriers, rapid response teams of security companies and utilities. Despite the affordability of the equipment, and the fact that, according to the Decree of the Government of the Russian Federation of October 13, 2011 No. 837, 27 MHz radios are not subject to registration, it is necessary to take into account the fact that civilian range subject to large atmospheric and industrial disturbances and the use walkie-talkieCB band for commercial purposes is not suitable for enterprises where high-quality radio communications are needed. Portable CB radios, due to the small radius of action and relatively large dimensions, they have not received much distribution and are used mainly in loading and unloading operations or in truck parking lots.
Most of the CB radio stations available in Russia are presented in our online store.
CB radio to buy which you can in our online store are presented in .
Low-Band range - 33-57.5 MHz
This is the lower section of the VHF mobile radio band.
Due to the large influence of industrial interference in cities and interference from TV broadcast transmitters, this range is used mainly in rural areas. The main users, since the times of the USSR, are ambulance stations and agricultural enterprises. To date, most of the world's manufacturers have stopped producing radio stations for these frequencies. Equipment for the Low-Band range, in this moment, are offered by domestic manufacturers - Granite and Vebr companies. In warehouses, you can still find radio stations from famous brands: Motorola GP340, GM360., Vertex Standard VX-3000L. Alinco, Inc. remains the only available foreign manufacturer of equipment in the 33-57.5 MHz range. The company offers the DJ-V17L portable radio and DR-135LH and DR-M06R car (base) radios.
Air range - 118-137 MHz
Aircraft carry out radio exchange between themselves and with ground services in this frequency range. Unlike most other types of VHF communications, amplitude modulation is used. Popular equipment for the air range -
wearable aviation range radios:
156.8375-174 MHz - mobile and fixed terrestrial communications.
In accordance with the basic law "On Communications" dated July 07, 2003 No. 126-FZ, in order to organize radio communications in this range, it is necessary to obtain permission from the Federal State Unitary Enterprise "GRCHTs". If it is necessary to obtain frequencies, we can provide consulting and accompanying support in obtaining permits.
High noise immunity and good signal transmission have made the 136-174 MHz band the most popular among users and equipment manufacturers. Most of the popular models of VHF radios and antennas are presented in our store. walkie-talkiesVHF band in our shop are presented in .
River range - 300 MHz
Used for communication on inland waterways.
Operating frequencies of walkie-talkies are in the range of 300.0125-300.5125 MHz and 336.0125-336.5125 MHz.
River Range Walkie Talkie comes with pre-installed channels dedicated to communication with ships and shore services, for one purpose or another.
Channel radio frequencies- their numbers and purpose are established by the "Instructions on the organization of ship radio communications in the basin (region)", approved by the River Fleet Service of the Ministry of Transport of the Russian Federation and agreed with local authorities of the State Supervision of Radio Communications. So, the main channels are:
Channel 2 (300.05 MHz) - for communication between ships;
Channel 3 (300.1 MHz) - for communication with gateway controllers;
Channel 4 (300.15 MHz) - for communication with other river fleet services;
Channel 5 (300.2 MHz) - for calling ships, coordinating the order of divergence and overtaking when maneuvering and transmitting distress signals.
Channel 25 and 43 (336.2 MHz and 300.125 MHz) are commonly used for communication between yachts.
All radio stations installed on ships, on inland waterways, must necessarily have the Permission of the River Register of Russia (RRR) and the Certificate of the Ministry of Communications, regardless of their ownership and whether these radio stations are the main or additional equipment.
According to the frequency allocation approved by the International Telecommunication Union (ITU), all over the world for communication between ships (rivers and seas) frequencies in the range of 156-162 MHz are used. The 300 MHz river band is used only in Russia and the choice of equipment offered for this band is small. Popular river radio stations: Radioma-300, Vertex Standard VX-451/VX-454,.
VHF range - 400-470 MHz
In foreign sources, the range is referred to as UHF, the name of which is derived from capital letters Ultra High Frequency.
The distribution features of UHF frequencies make it possible to recommend this range for use in dense urban areas, in the mountains. In forest conditions, radio stations at 400 MHz are inferior to radio stations in the 136-174 MHz range.
In the range, frequency bands are allocated for professional use, for radio amateurs and for unlicensed use by everyone.
Radio frequencies, whose operation, in accordance with the basic law "On Communications" dated July 7, 2003 No. 126-FZ, is possible only if there are permits:
420-430 MHz - mobile and fixed terrestrial communications;
430-440 MHz - amateur radio band;
440-470 MHz - mobile and fixed terrestrial communications.
If it is necessary to obtain frequency ratings, we can provide consulting and accompanying support in obtaining permits.
Sections of the range, which, according to Decree of the Government of the Russian Federation of December 31, 2004 No. 896, do not require permits - allowed radio range(unlicensed frequencies):
433.075-434.775 MHz - LPD ("Low Power Device") range. Standard frequency grid of 69 denominations, with a step of 25 kHz;
The hunter got lost in the forest. He walks through the forest, calls his comrades and yells at the top of his lungs:
Awwwwww!
A bear comes out to meet and asks:
- What are you yelling at?
- Yes, I got lost, I think, maybe someone will hear.
- Well, I heard it got easier?
Laughter with laughter, but in every joke, as they say, there is some truth. Good communication on hunting, fishing, hiking, scientific expedition is no less important than, for example, the presence of a compass and a map. This is especially important when you are in an area that is still unknown to you. I remember one incident told by a familiar huntsman. One hunter strayed from the main group on a stalking hunt and got lost. He was well equipped. There seemed to be nothing to be afraid of. But it turned out that the scale of the map he had did not allow him to get attached to the terrain, and the compass turned out to be useless, since from the very beginning, he did not take any landmarks, apparently hoping for a chance. Cloudy, winter day. There was a thaw, the snow was almost gone. No snow, no trace. It only remained to hope for good luck and a radio station issued by the organizer of the hunt. However, he deviated so far that he had to circle through the forest for more than one hour before the radio speaker hissed. Only then the huntsman, who knew the area well, was able to lead the lost hunter to the rest. The hunt, of course, was thwarted, but at least the man was not hurt. Another example is also significant. This time no one got lost, but the hunt was spoiled by "bad" radio stations, which in the forest, unexpectedly, began to catch the voices of distant countries and the negotiations of the capital's policemen. But it was not the walkie-talkies that were to blame, but the hunters who had incorrectly selected their range. And in the first case, if the radio stations were more powerful, you might not have to spend all day searching for the missing client. So, the purpose of this article is to help hunters, fishermen, tourists and people involved in extreme species in the objective choice of radio communications, which are as important as the right cartridges for hunting, baubles for fishing or ropes for climbing. to the mountains. Among the huge variety of radio stations that are presented on the modern market, everyone must choose the one that is best suited for solving his specific tasks. But before proceeding to a description of the types and types of radio stations, I offer a small educational program on the theory of radio wave propagation, which will at least help an inexperienced reader understand why some radio stations work further than others, although they have approximately the same technical characteristics. Currently, in Russia, the State Committee for Radio Frequencies (SCRF) has allocated the following main ranges for the operation of land and mobile radio communications:
In order to determine which range is the most optimal for communication in the forest, on water or mountains, let's delve a little into the theory of radio wave propagation in the ranges I have indicated. Corresponds to a wavelength of 11m. Radio waves in this range are strongly absorbed by the soil, the connection depends on solar activity. They are able to overcome obstacles in the form of small hills, slopes, buildings 10-15m high. As a rule, short-range communication on this range is carried out by a surface wave (propagates along the earth). When propagating as a sky wave (reflected from the ionosphere), communication is possible for many thousands of kilometers. In practice, this looks simple. The entire broadcast is filled with signals from radio stations that are thousands of kilometers away from you, but you will not hear your neighbor, who is, say, a kilometer away. There have been cases when a person said "one", heard the echo of his voice, which was heard from the speaker. This radio wave turned around the globe, due to many reflections from the ionosphere and returned to its starting point! Corresponds to a wavelength of 2m. In this range, radio waves propagate by direct and reflected waves. Since the surface is not flat, but spherical, the radio communication range is several tens of kilometers. If the antennas of radio stations are located at a height of several tens of meters from the ground, then communication is possible at a distance of up to 100 km. The propagation of radio waves in this range is significantly affected by the terrain, all kinds of obstacles, etc. For example, deciduous forest in this range introduces attenuation of the order of 6dB/100m. At different points of reception, the signal level can be different and range from strong confident reception to a complete loss of radio communication. This is due to the fact that at different points of reception, the surface and reflected waves arrive in phase or antiphase. Accordingly, in this case, the strength of the electromagnetic field is added or subtracted, which ultimately affects the level of the received signal. The influence of atmospheric interference, time of day does not significantly affect the propagation of VHF radio waves. Therefore, the connection here is stable at any time of the day. In buildings and reinforced concrete structures, VHF radio waves propagate poorly. . Corresponds to a wavelength of 70 cm. With an increase in the frequency used, the influence of weather conditions increases and the communication range decreases, since the propagation conditions of radio waves in this range approach those of light propagation. Microwave radio waves propagate well in the city due to reflection from buildings and reinforced concrete structures. In the forest, radio waves of the 400 band propagate worse than VHF. For example, deciduous forest in this range introduces attenuation already 10dB/100m. Also, radio waves of this range work well in the mountains, especially in crevices and gorges. Radio communication over short distances in this range is stable and does not depend on the time of day. From the properties of the radio wave bands I have given, we can conclude that for communication in forest and rough terrain, radio stations in the 27 MHz and 136-174 MHz bands are preferable. For the city and mountains, on the contrary, it is better to use radio stations in the 400-470 MHz range. Now let's try to understand the types of radio stations that are presented on our Russian market. All radio stations can be divided into 3 main groups:
Portable radios
Mobile radios
Base radio stations Portable radio stations. First of all, a radio station is an electronic device that consists of a transceiver, an antenna and a power source (battery or battery case). Sometimes radio stations are also called transceivers. This means that some radio units are used together for receiving and transmitting in order to save space and product cost. According to their consumer qualities, radio stations are divided into several types. Professional radios tend to follow the international military standard. This means that the chassis of the radio station is a one-piece molded body, and the top and bottom panel of the radio station is made of impact-resistant plastic. All rubber gaskets, under which the transmission and control buttons are hidden, fit snugly against the body of the radio station so that water and dust do not get there. In a word, these are radio stations that are not afraid of splashes, dirt, dust, vibrations, heat and frost. The LCD indicator, if any, is located so that it will not be damaged during a fall. All professional radios have a minimum of keys and controls. As a rule, this is a channel switch, volume control and 2-3 programmable keys. Currently, almost all professional radio stations are programmed from a computer. To program the radio station, special interface cables and software are used, which are manufactured by manufacturers of radio stations. The auxiliary keys of the radio station can be programmed so that they switch power, backlight, turn on and turn off the speech masker, etc. Almost all professional radio stations operate in simplex mode (reception and transmission at the same frequency) and half-duplex (reception and transmission at different frequencies). The last mode is designed to work through a repeater. Professional radio stations of the middle class have, as a rule, 16-32 programmable channels. The noise suppressor, for these stations, is electronic and its response threshold is programmed from a computer. Many professional radios have a selective call feature. This function is needed when several groups operate on the same frequency. The members of each group have their own individual or programmed into the radio. As a result, members of one group enter into radio communication with each other. At the same time, members of other groups do not hear them and also communicate with each other. Thus, there is a code separation of the communication channel. As a rule, all professional radio stations are produced with one range. There are 2 main versions: 136-174 MHz and 420-470 MHz. The latter, in turn, are divided into sub-bands: 400-430 MHz, 450-490 MHz, or, for example? 400-470 MHz. Amateur radio stations, unlike professional ones, do not have fixed programmable channels, but a smooth digital scale. As a rule, they have a keyboard with which you can enter the operating frequency in the range of 136-174 MHz and 420-470 MHz. One of the main differences between amateur radio stations and professional ones is that the first ones are programmed completely from the keyboard and no programmers are needed for them. They also have memory channels. There are many more of them in amateur radio stations than in professional ones. The latter, as a rule, only display the channel number on the LCD or on the channel selector. Amateur radio stations, in addition to the channel number, also display the operating frequency. And in terms of the number of auxiliary functions, they are much superior to professional ones. In an amateur radio station, you can set the frequency step, the frequency of the subcarrier subtone, the output power, the spacing between reception and transmission, and much more from the keyboard. Radio amateur radio stations have a developed auxiliary menu system. At the same time, only the main functions that are most often used by the user are placed on the keyboard. Amateur radio stations are the most versatile in use. They have a built-in received signal level meter (the so-called S-meter). There are also 2-band amateur radio stations that have 2 operating frequency bands: 136-174 MHz and 420-470 MHz. They are the most versatile. They can be used both in the forest and in the city, mountains. Some models of these radios have a built-in scanner, ie. receiver with an extended frequency range from 500 kHz to 1000 MHz. Some can even be equipped with additional modules for measuring air temperature, atmospheric pressure and altitude. Currently, there are a large number of amateur radio stations, the body design of which complies with the international military standard MIL STD 810 C, D, E. The Japanese company VERTEX STANDARD went even further. It currently manufactures the VX-6R and VX-7R waterproof radios. These radios can be submerged to a depth of 1 meter for 30 minutes. , as a rule, are installed on moving objects. For example, cars or snowmobiles. Unlike portable radio stations, they have an output power of 30-70 watts and therefore operate from the batteries of the car's on-board network. As a rule, these radios are equipped with external communicators, which have a microphone and a transmit button. Mobile radio stations according to their functional purpose are also divided into professional and amateur. Professional mobile radio stations comply with the international military standard MIL STD 810 C,D,E, are made on the basis of cast aluminum chassis and are covered with impact-resistant plastic. In terms of functionality, mobile radios are not much different from portable radios and are also programmed from a computer. Amateur, mobile radios are available in both conventional and shockproof housings. They have a smooth digital scale and allow you to dial the operating frequency from the keyboard, which is located on the remote communicator of the radio station. Mobile radio stations, as well as portable ones, are released on the range of 136-174 MHz and 420-470 MHz. Professional radio stations in the microwave range can be produced on certain sub-bands. For example, 400-430 MHz or 450-490 MHz. Professional mobile radio stations are available in single-band VHF and microwave bands. Unlike professional mobile radios, amateur radios come in dual-band and even duplex. These radios sometimes have a built-in interband bidirectional repeater mode. They have a large number of various functions that can be called both from the keyboard and from the buttons on the front panel. These radios are not designed for 24/7 operation and are therefore rated for 50% duty cycle. Professional radios, by virtue of their design, are designed for round-the-clock operation and have a 100% duty cycle. Mobile radios are connected to external car radios with different types of mounts, which are tuned to the operating frequency. The same mobile radios are used as base radios, only instead of a car antenna, a base one is connected via a coaxial cable with a wave impedance of 50 ohms. In this case, the radio station is powered from an external stabilized power source with an operating voltage of 13.8 V and a current of up to 15 A.
Good time of the day. This information will be of interest to those who have already decided on a model that undoubtedly meets your aesthetic and consumer needs.
When choosing which one you need to pay attention to, with what frequency you have to work. Each state, being the owner of radio frequencies, establishes a number of significant restrictions on their use. Based on this, walkie-talkies are divided into two main types - professional and amateur. Ham radios have authorized power and can be used without a special license. But to use professional walkie-talkies, you will need to register the device.
So, in the line of radio transmitting devices we offer, you can see portable or mobile transceivers designed for operational communication, frequency range and MHz.
Radio stations in the CB (CB) band, short for "civilian band" (eng. CB, Citizens' Band), adopted to refer to unlicensed, accessible to all citizens, short-wave radio communications in the 27 MHz band are used all over the world, usually by motorists.
If your attention was attracted by single-band walkie-talkies with a frequency range of 400-470 MHz, then you need to know what this includes:
Walkie-talkies with the range of the LPD 433 standard, (Low Power Device) - a radio frequency range of 69 channels in the range of 433-434 MHz for low-power devices up to 0.01 watts. This frequency range is the same as the European range for a similar application;
PMR (Private Mobile Radio, PM) is a European license-free system (colloquially referred to as PMR446) of mobile radio communication in the VHF band with a frequency of 446.000-446.100 MHz and with a maximum output power of 0.5 watts. It is intended exclusively for private use and to meet the domestic needs in radio communication of the general population.
As noted above, walkie-talkies with such frequency ranges are amateur, do not require licensing and registration.
Particular attention should be paid to single-band radios with a frequency range of 136 -174 MHz. VHF (VHF), more precisely, part of the VHF range - from 136 to 174 MHz; in Russia, it is necessary to obtain permission to use a radio frequency (rent a frequency) at the Radio Frequency Center and register walkie-talkies with the State Committee for Supervision. This is explained by the fact that mobile telephony, television signal transmission, satellite communications, radio communications of law enforcement and security agencies, military communications, aero communications and so on are carried out in this frequency range. The frequency range is professional. Also in this range there is a narrow frequency band - 144-146 MHz, allocated for radio amateurs (it is required to pass an exam for a category, register a radio station with the State Committee for Supervision).
Dual-band walkie-talkies are of interest. The frequency range will look like this - 400-470 / 136-174 MHz. Such radios also work in amateur band and professionally. It will be possible to use the LPD 433 and PMR446 standards at permitted frequencies, and in case of a critical situation when assistance is needed from the Ministry of Emergencies, law enforcement agencies, etc., use the 136-174 MHz range.
I hope that this article will help you finally decide on the radio model and get a reliable assistant for work and leisure.
Decree of the Government of the Russian Federation of October 13, 2011 No. 837 "On Amendments to the Decree of the Government of the Russian Federation of October 12, 2004 N 539" from the list of radio electronic equipment and high-frequency devices subject to registration, land mobile communication stations for personal use in the 27 MHz band were removed (CiB range) with a permissible transmitter radiation power of not more than 10 watts.