Automotive radio station 144. Reviews and useful information for radio amateurs. VIII. Installation of radio
When we leave, we leave, fly away,
When we settle our cars,
What will be empty paths here,
How will be without us alone tops.
Lies my heart on a difficult path,
Where the comb is high, where the crimson rocks,
Lies my heart, does not want to leave -
For a small walkie-talkie signals me.
Yury Vizbor.
Everything that will be discussed below is not theoretical knowledge or assumptions, everything is tested not by one tenth jeepers in practice in a variety of expeditions. The article has a practical goal - to help choose racies and antennas for automotive travel. And, first of all, it will be useful to those who are solidary with the Brothers Strugatsky - "And what is the point to buy a car to drive around asphalt? Where asphalt, nothing interesting, and where it is interesting, there is no asphalt ".
Well, let's go!
I. On the need for a road trip.
Any car journey begins long before we sit down in the car and turn the key to the start. Automobile journey outside roads is often called "Expedition", and it begins with careful planning, preparation and equipment of the machine for the passage of the route.
Open a new way for which no one has ever passed, to drive where there is no, and never had any roads, no matter how old you do not count yourself, one car is unlikely to succeed.
The passage of a complex route outside the roads implies the operational interaction of all participants in the expedition.
Communication on the radio allows you to instantly coordinate actions when the help of other crews is required, and the timely exchange of information makes the trip more secure.
You are always aware of what is happening on the route. You are not alone.
Of course, it is possible and without a walkie-talk, but maybe then the most vivid impressions of the trip will be the questions you started in the air that you will start to ask yourself without having left the city - "Why stand?" And "Why did he go there?".
For people traveling on cars, the need for radio communications is obvious.
II. How to use a walkie?
Configure the radio in all machines to the same frequencies (channels). You need to say something - press the transmission button on the tangent and speak, let go and listen. That's all science.
But, if seriously, I want to go about what -
Of course, it is nice to go to the column and communicate with other crews, but the main purpose of the radio is to inform about non-standard or dangerous situations, i.e. Ensuring passive traffic safety.
Moving in the middle or tail of the columns and enjoying the types of beauty, we sometimes do not guess what happens in front and, on empty conversations, we can miss important information - a detour, counter movement on a narrow road and so on. The head machine of the column, as a rule, informs about all the observations - a stone on the road, a deep rut, a middleman, a comfortable trailer, a reversal for a secondary road. The closing machine must inform that everyone turned to a country road, about the entrance of the entire column on the special compliment and the exit of all cars with a special exam.
Try not to download ether empty conversations. Under the congress from the asphalt and the output on the special complimentary, do not occupy chatter ether. The security of all expedition participants depends on the operational and received information.
Do not load the ether.
III. What is the most important thing in the walkie-talkie?
The main thing in the radio is due to the range and reliability.
Your comfort depends on the reliability of the radio station - you can conduct a mini-meeting without leaving the car, to share seen, report short stops so as not to delay the column.
And, very important, the safety of all participants in the reliability of the radio station depends on the reliability of the radio station - operational warnings about steep slopes, possible embodiments, the oncoming movement on a narrow road are able to prevent trouble.
It is important that the radio does not fail.
When choosing a radio station, pay attention to the manufacturer's specification. For example, reliable car radio meets MIL-STD-810 standards, some radio stations correspond to the Claiming Class IP54 and above. Manufacturers are indicated.
Currently, there are very many Chinese production radio stations and, unfortunately, not always good quality. Want a reliable radio - give preference to known, proven brands.
Briefly about the range (radius) of communication.
Communication range is the maximum distance at which radio communications is possible.
Communication range depends on the following parameters:
External natural factors: solar activity (atmosphere ionization state), meteorological situation and time of day;
Terrain;
Range of radio stations;
Transmitter output power;
Receiver sensitivity;
Antenna gain coefficient;
The correctness of the antenna is installed.
We cannot affect external factors that limit the distance of radio communications, but we can choose equipment with technical characteristics that would most comply with our requirements.
Now let's try to figure it out.
IV. Used frequencies of radio stations in automotive travel. Pros and cons of different ranges.
In different cities, off-road clubs use radio stations of different ranges.
For example, Jipers Krasnoyarsk, Kyzyl, Abakan, Minusinsk, Vladivostok, Irkutsk, Novosibirsk often use a range of 144 MHz. Kemerovo, Novosibirsk, Barnaul, Tomsk - 27 MHz, less often 144 MHz, there are 430 MHz. Moscow and the area mainly - 27 and 430 MHz.
The following frequencies are used in Krasnoyarsk:
144.750 MHz - Enese Yenisei Odyssey;
144.825 MHz - the main jeeper frequency of Krasnoyarsk;
144.950 MHz - Club polyoffs;
145.300 MHz - UAZ-Patriot club;
145.325 MHz - UAZ-Patriot Club Spare Channel / Club Yattractor;
145.725 / 145.125 MHz - Radio-Resistant Repeater Included in the Unified Siberian Radio Piece VHF;
159.825 / 158.125 - City autocanal (frequencies provided by the company), is connected to the 40th Civil Range Channel of 27.405 MHz.
In Kyzyl:
145.275 MHz - Adyg Club;
145.325 MHz - Adyg Club Backup Channel.
In Irkutsk:
145.400 MHz - Club Protector.
In Tomsk:
145.300 MHz - UAZ-Patriot club.
On the Internet, information scattered and contradictory, but one thing is clear - there is no one standard for Jeeper brethren. We will be happy if you know what bands for communication are taken in your region, preferably with specific frequencies. In travels in Russia and the nearest abroad, such information could all be useful to us.
Pros and cons of different ranges.
If you have a theoretical cumulative calculation, taking into account the curvature of the earth's surface of the terrain and natural obstacles, then the maximum possible radius of radio communication by 27 MHz will be greater than on the ranges of 144 MHz or 430 MHz. It is connected with radio wave physics. 27 MHz - wavelength of 11 meters and this frequency is able to encourage the surface irregularities with a diameter of 5-6 meters (1/2 of the wavelength of the range). Partially, due to refraction, the Fresnel zone is slightly expanding. The zone of Fresnel is direct visibility, which is calculated by the formula d \u003d 4.11 ((n) 1/2 + (h) 1/2), where D is the maximum range of sight (KM), N and H - the height of the lift of the reception and transmitting antennas (m). Theoretically, the maximum possible range on the Siberian range can reach 80 km. In practice, a large level of atmospheric and industrial interference from power lines, the electrical equipment of the car has a negative impact on the range of communication on this range. Add a low efficiency of automotive antennas to this range (let's talk about this below) and it turns out that in practice 27 MHz is seriously inferior to the ranges of 144 MHz and 430 MHz.
It is worth adding that 27 MHz is the border of the VHF and the RV ranges with their specific properties. In this case, one of the unpleasant properties of a range of range (frequency up to 30 MHz) is the ability to a lot of jumping passage with a reflection of the signal from the layers of the ionosphere. Often, especially during the maximum of solar activity, the concentration of ions in the layers of the ionosphere gives them a reflective ability and at such moments the bonds of the tropospheric passage of a straight wave are greatly difficult - the local correspondent signals are drowning in noise and cods from distant stations.
Consider the pros and cons of the use of radio stations of different ranges.
27 MHz, or Civil Radine Range or Si Bi Range.
The low cost of equipment, for example, the price of an inexpensive good kit, will cost no more than 5800-00 rubles;
Opportunity to communicate with truckers on the track (15am channel, frequency 27.135 MHz);
Radio stations for a range of 27 MHz do not require registration.
A small radius of action - as much as possible up to 15 km, on average - on open spaces 7 km, in the forest 3-5 km;
Low communication quality - the range of 27 MHz is strongly susceptible to atmospheric and industrial interference;
The radio station at 27 MHz is sensitive to interference from various electrical equipment of the car. Large interference creates blocks of ignition xenon, pulse blocks of registrars, navigators, voltage converters (inverters);
Antennas at 27 MHz at the base have a matching coil, which in the forest it is easy to damage even a small branch;
Manufacturers on this range do not offer reliable wearable radio stations that could be recommended to communicate "Pilot-navigator".
Range 144 MHz.
Of all the ranges, the largest radius of action between cars is possible at exactly 144 MHz - under forest conditions up to 25 km, in open areas up to 50 km;
The possibility of using short antennas about 50 cm long with a spring base. Due to the small size and durable, simple, design, such antennas are able to withstand even strong blows of branches;
Good communication quality. The range of 144 MHz is not subject to atmospheric and industrial interference, the equipment of the car practically does not have any interference to the work of the radio station;
At 144 MHz there are automotive radio stations with protection against the external environment relevant to the IP54 standard. Most radio stations on this range correspond to the MIL-STD-810 military standard and are able to withstand serious vibration loads. Radio stations at 144 MHz, as a rule, are more reliable compared with radio stations at 27 MHz;
On the 144 MHz range, a large number of portable radio stations are offered, which can be used to communicate "Pilot-nastrum" for possible hiking trains and for communication with the base camp, in hiking during trips.
Range of 430 MHz.
A large range of action, which is only a bit inferior to the range of 144 MHz - under forest conditions up to 20 km, in open areas up to 50 km;
The possibility of using short antennas capable of withstanding even strong blows by branches;
Good communication quality - a range of 430 MHz is not subject to atmospheric or industrial interference, the equipment of the car does not have any interference to the operation of the radio station;
At 430 MHz there are automotive radio stations with protection against the external environment relevant to the IP54 standard. Most radio stations on this range correspond to the MIL-STD-810 military standard and are able to withstand serious vibration loads. Radio stations for 430 MHz are usually more reliable compared with radio stations by 27 MHz;
On the range of 430 MHz, a large number of portable radio stations are offered, which can be used to communicate "Pilot-navigator" for possible hiking trains and for communication with the base camp, in hiking during travel.
The cost of the radio station with an antenna is higher than on the range of 27 MHz - the price of a good set of warning with an antenna begins from 14 thousand rubles;
The need for a radio station is required for which it is necessary to obtain a radio amateur call.
By the range, the quality of communication and reliability of the equipment is the first place ranks 144 MHz. For the range of communication under the conditions of the forest, it is inferior to the range of 430 MHz. And the most not good choice for automotive travel, this is a range of 27 MHz. The real range of communication between two cars with 27 MHz and two-dimensional antennas in the same conditions will be approximately three times less than between machines equipped with rates on the ranges of 144 or 430 MHz with short antennas. In small distances, the quality of communication at 144 MHz or 430 MHz will be significantly higher, since there are practically no interference at these frequencies.
On various off-road forums, there are discussions in defense of 27 MHz. At the same time, the range of communication and reliability - i.e. The main, most important, characteristics of radio stations, in such discussions, unfortunately, are not taken into account. The following "arguments" are usually given:
All so and therefore no one will go to other radio.
It is not quite true, just look at the equipment of the majority of major expeditions to understand what it is not. In serious automotive travel, there are cases when the distances even on 144 MHz or 430 MHz are not enough.
27 MHz radios do not require registration.
According to the law, equipment at 144 MHz and 430 MHz must be registered, but, first, you need to get a radio amateur call sign. The procedure for obtaining is described in detail in the article. An important point is permission issued for the right to operate and by law you can buy a walkie-talkie, you can install in the car, but it is impossible to use. If there is no permission, then at the time of the stop by employees, the radio station must be turned off, in this case there should be no questions. In Krasnoyarsk, the last case of administrative impact for the use of a radio station without permission was ten years ago. However, this does not mean that everything will be fine. As the situation with loyalty to jeusers in other regions, I do not know, so I highly recommend permission to get, especially since there are no difficulties in this. Registration of the radio is not the passage of those. Regulations, it is really simple.
Low price equipment.
We hope that this argument is given in the form of a joke. Almost any off-road trip suggests the presence of at least one winch, the presence of extension cores, coskers, polyspast, haygek, GPS navigator, and, as a rule, we do not save on this - the price of this equipment is not the main selection criterion. To buy a radio station should be approached in the same way - the main quality is quality and reliability.
V. Effect of capacity for communication range.
Radiocommunication range The value is not constant and depends on the relief of the terrain and natural factors. Radio communication at 27 MHz depends on the state of ionization, weather and time of day, much stronger than radio communication by 144 MHz, and the range of 430 MHz is exposed to natural conditions. The higher the frequency, the less the influence of natural factors. In addition to external conditions for the range of communication, such technical parameters of the radio station are influenced as the power of the transmitter and the sensitivity of the receiver.
The dependence of the range from the transmitter power is proportional to the fourth degree. This means that in order to increase the range of communication, the transmitter power must be increased four times. To increase the range four times - power will need to increase at sixteen times and so on.
In practice, this dependence is valid only under clean ether. In the presence of industrial or atmospheric interference, the gain of the distance from increasing power will be more serious. On the ranges of 144 MHz and 430 MHz interference, very little and the dependence of the radiation range from the radiation power will be less. At 27 MHz, the difference in the range of communication from the transmitter power is more noticeable.
At 27 MHz, most of the radios have an output power of 8 W or 18 W (usually more powerful radio stations have in the title "Turbo" console). The difference in the distance between 8 and 18 W will be especially noticeable in the conditions of mountainous terrain and in the conditions of a dense urban building. On open spaces, in the absence of interference, there will be no difference in the communication range. But with Optim-778 is a radio station with a maximum power in amplitude modulation (AM) 25 W and 50 W in frequency modulation (FM) difference in the quality and range of communication, compared with 8-watt radio stations will be noticeable on open plains. Spaces.
At 144 MHz and 430 MHz radio stations are made with the output power of the transmitter 25 or 50 (45) W. In the range of 144 MHz, at maximum distances, with a transmitter power, 50 W can be calculated to increase the range, compared with 25 watt radio stations, by 25%. At 430 MHz, the range of communication to a greater extent depends on the terrain relief and the output power of the radio station to the range practically does not affect.
Vi. Sensitivity of the radio station.
The sensitivity of the radio station receiver is one of the most important parameters. Sensitivity is measured in microvolts. Good radio stations sensitivity is the tenths of the microvolt. Than this figure below, the better. At different manufacturers, the methods for determining and comparing sensitivity may differ. It is important to pay attention to the value of the signal / noise ratio, at which the manufacturer indicates the results of the sensitivity measurement. Some manufacturers indicate the sensitivity value at an extremely low signal / noise ratio when the signal is already lost behind the noise. For normal operation, there must be a measurement at a ratio of C / w at least 10DB, sensitivity is often measured at a ratio of C / W 12DB. Unfortunately, no rare cases when manufacturers in specifications indicate not entirely correct or objective information. This is due to the fact that there are several standards for measuring this parameter. If you have doubts about the information provided by the manufacturer for the consultation, you can contact our laboratory.
The main thing is that you need to understand - the better the sensitivity of the radio station, the more potentially it can work for a greater distance. For example, a radio station with a sensitivity of 0.12 mkv, with other things being equal, "hears" is about 2 times better than the radio station with a sensitivity of 0.5mkv.
VII. About antenna.
Now we know how the range of communication depends on the power and sensitivity of the radio station. But! A much greater degree of range depends on the correct choice, installation and settings of the antenna. Therefore, when buying an antenna, it is very important to make the right choice, the correct installation of the antenna and its configuration are also important.
Main Antenna Lifehaki:
1. The longer the pin the antenna, the better.
2. The higher the machine is installed antenna, the better. For the highest possible operation of the antenna should be installed on the roof of the car. The higher the antenna will be raised, the greater the range of the radio. The height of the antenna is directly proportional to the possible range of communication.
3. In close proximity to the base, the coil and the the antenna itself there should be no metallic objects.
4. The car body is the second part of the antenna and serves as a counterweight. The coaxial cable braid at the base of the antenna must have reliable electrical contact with the car body. If the antenna is installed on a magnetic base, then the capacitive bond with the body is carried out due to the foil located at the bottom of the magnet, to which the antenna cable braid is connected. Foil should not have damage.
5. Antenna must be configured! Only using the full potential of the antenna can be achieved the maximum quality of communication.
6. The antenna can be slightly tilted. But, with a tilt of the pin more than 45 degrees, the antenna vertical radiation angle will be directed to the Zenith and the long distance of the radio will not work.
One of the basic characteristics of the antenna is the gain coefficient.
The gain of the antennas is measured in decibels. An antenna amplification point is considered either an isotropic emitter is a theoretical antenna, which has an efficiency of 100% and an indirect amplification, or the point of reference is considered a half-wave dipole with shoulders equal to 1/4 wavelength. In case, after the reinforcement numbers, the manufacturer specifies the DBI letters, which means the point of reference is the isotropic emitter. If the DBD letters are standing after the gain figures, it means that the half-wave dipole is received per point of reference. Regarding the isotropic emitter, the half-wave dipole has a gain of 2.15 DBI. In most cases, manufacturers indicate the amplification relative to the isotropic emitter.
A bit of theory. The wavelength is the distance between the two points closest to each other in space in which the oscillations occur in the same phase. Knowing that the speed of movement of electromagnetic waves is equal to the speed of light, it is possible to easily determine this distance by the formula λ \u003d 300: F, where F frequency in MHz.
The frequency wavelength of 144 MHz is equal to 2 meters and an antenna with a physical length of a pin 50 cm (1/4 λ) will be gained 2.15 DBI. Antenna at 144 MHz, with a pin length of 1.2 meters (5/8 λ) has a gain of 3.2 DBI.
At 430 MHz, the wavelength of 70 cm, the antenna is only 17.5 cm long (1/4 λ) will be gaining 2.15 DBI. Good antennas on this range, for example anli AW-6UHF, with a pin length of 75 cm have a gain of about 5 DBI.
27 MHz is a wavelength of 11 meters. Antenna with 2,15 DBi amplification, equal to 1/4 wavelengths should be 2.75 meters high. Therefore, what point of counting is taken by the manufacturers of the civilian antennas, indicating the positive gain of the gain to its antennas is unknown. Any size antenna is less than 1/4 λ, in any case, will have a negative gain.
What is important to understand? Since Decibel is a relative logarithmic value, exactly the same as multiplicity or percentages, and is intended to measure the ratio of levels of two values, then the winnings even in one decibel is very good. For example, 3 DB is equal to an increase in the power of the radio station twice, and 5 dB is equal to the increase in power three times.
And if it is very simple, the more the physical dimensions of the antenna (pin length), the higher the amplification and, accordingly, more radius of the possible radio communications.
The direction of the antenna.
Antenna's orientation is an indicator that characterizes the dependence of the reinforcement coefficient of the antenna from the direction. Any car antenna consists of two parts: the actual antenna itself, which is the emitter and the second part, is a car that is a counterweight. Counterweight, that is, the car on which an antenna is installed, forms a radiation diagram. The car antenna works best in the direction of more metal - if the antenna is installed in the rear of the car, then the maximum radiation is forwarded, if the antenna is installed in the front part, then the petal of the chart will be pulled back. The incidence difference in the horizontal plane can reach 3 DB. And more - the larger under the antenna metal, the radiation of the antenna in the vertical plane is more pressed to the horizon, which positively affects the range of communication, so the antenna installed in the roof center will work better than the antenna installed on the edge. In practice, these nuances are not particularly manifested, as the surrounding items, in the form of houses, trees and other obstacles lead to a signal to recycle. But if you want to squeeze everything, then know and use this knowledge in practice is useful. For example, if you take the correspondent in the noise, try to deploy a car to it so that in its direction it accounted for maximum antenna gain.
Install antenna.
The most correct installation of the antenna on the car is the insert antenna in the roof.
With a mortise installation, the cable and the base of the antenna will serve forever, and there is no need to think how to start the cable into the car. For mortise installation, it is better to use antennas having a unified PL standard connector (SO-239). Such antennas are put on mortise mounts, for example, the fastening is perfect, or similar to the U-221F standard connector. To install the connector, disassemble the roof cover. As an amplifier, we weld or fix on rivets to the transverse amplifiers of the roof of the iron sheet. Drills opening Ø16 mm in a sheet and roof. And install the connector, which is desirable to put on the sealant. In cases when an expeditionary trunk is installed on the roof, an antenna should be installed on the trunk. The connector in this case is used as an adapter to connect the cable to the antenna installed on the trunk.
There are also many options for installing antennas for various mounts -. Popular attachments for installing antennas for SUVs - fastening on the drain, fastening on the back door, fastening to the railing and fastening on round arcs of the expedition trunk. Although, the trunk is best - easier and more reliable, in the corner of the top basket to weld the horizontal platform. When installing an antenna, do not forget at the point of installation of the antenna, directly on the connector, ensure reliable electrical contact with the car body. When installing an antenna on the trunk or railing, it is necessary that all the attachment points of the trunk or the rails have reliable contact with the car body. If the antenna does not have contact with the body, then it does not make sense to burn the wire to the mass in most cases. Such a wire will be a certain LC chain and unpredictably affect the operation of the antenna. In rare cases, it helps, but the wire must be as short as possible and the most fat.
And, perhaps, the worst thing is that you can come up with antennas for radio communications, and for installation in a jeep it is "the worst" multiply by 100, this is a magnet. In the forest, any, even a slight blow by a branch of an antenna will lead to the fact that the antenna flies off the roof and the ability to cut the cable from the magnet or damage the antenna itself.
Antenna setup.
To obtain the maximum possible distance of the radio, the antenna must be configured. It is very important.
Surely everyone heard about the configuration of the antenna at a minimum of the KSW - the coefficient of the standing wave. Let us forgive us colleagues, but whatever go beyond the framework of the article formulate the concept of the CWS as a ratio of power, which goes through the cable before the antenna and the power, which returns to the cable, reflecting the antenna due to the fact that the antenna resistance is not equal to the cable resistance. The perfect CWW is 1, with KSV 1.5, 4% of power is lost, 10% is lost at CWS 2. KSV less than 2 can be considered acceptable. The CWS is about 3 unacceptable, since with such values, the radio station reduces the power of the transmitter and a good range of communication will not be, and in some cases the high KSW can entail the output of the radio station.
If the antenna is proper and correctly installed, then, in most cases, you can configure an antenna using. But, there is another important parameter, about which many forget this reactive resistance. The antenna best radiates or receives electromagnetic oscillations when the frequency of the exciting oscillation coincides with the resonant antenna frequency. On the resonant frequency, the reactive resistance of the antenna will be minimal. The minimum of CWS does not always coincide with a minimum of reactive resistance. The KSV meters show only the value of the standing wave coefficient, therefore, it is better to use the antenna antenna antenna for careful settings. For example, well established themselves. For a household, this is, of course, expensive, but if you purchase such a device to the club, it is possible and justified. And you can configure the antenna with us, in, for jeepers, the configuration is free.
VIII. Installing a radio.
According to statistics, properly installed radio stations are much less likely to repair.
Power supply must be directly from the battery, on the plus wire it is necessary to provide the preservation of the fuse at least 15 cm from the battery;
The radio must be installed so that it can be convenient to use;
The tangent cord should not be stretched;
Necessarily, in a convenient place, install the fastening (holder) tannts;
The radio should not blow up air flows from the air ducts and should not be under direct sunny rays;
If it is planned to overcome large brodes, it makes sense to establish a radio station in the ceiling console.
It seems that it is all that should be considered when installing a radio station in the car.
Now we know that for communication in the forest and inside the column it is preferable to car radio stations by 144 or 430 MHz, whereas will exchange useful information with truckers, which use the wounds of the SI-Bi range of 27 MHz?
The answer is simple - the expeditionary car must have two radio stations - one by 144 or 430 MHz, for communication inside the column and the second - by 27 MHz to communicate with truckers.
Antennas at 27 MHz to ensure good communication should be considered with a pin height from one and a half meters and above. The choice of antenna is very large. Note - this is a classic, - it has a more powerful base and, probably, there is less chance to break, - this antenna has a mechanism at the base of the antenna with a frontal blow to the antenna and chances to break such an antenna in the forest even less. The maximum radius of action can be achieved using an antennas with a pin length of 2 meters. If you plan an antenna installation is not on the roof, but, say, on the power bumper or on the gate of the spare wheel, you should also consider the antennas with the pin height of two meters - this is at least some compensate for the "curve" installation. Good two-meter antennas - and their analogues. These antennas work are better short, but also to break them easily - in their foundation, as well as in the antennas at 27 MHz, there is a mechanically weak part - a matching coil. A little more reliable is an antenna 5/8 λ, with a matching coil, but the coil is made in the form of a spring.
At 430 MHz, a good radio station with the possibility of manually input frequency. This is a radio station radio station with the possibility of manually input frequency in the range of 400-470 MHz.
For harsh operating conditions, it is better to stop your choice on professional UHF range radio stations - ,.
Common antennas for a range of 430 MHz - ,.
X. Final part. Communication does not happen much.
If you think that two radio stations in the car are a lot, then I will give an example. In my car installed a Motorola DM3600 radio station and the Yeesu FT-857 Vesvolta Transceiver. Motorola DM3600 is used to communicate with jejers and for communication in the DMR network, Yaesu FT-857 to communicate with truckers and communications with radio amateurs. It doesn't matter how far from home, through radio amateurs can always be transferred to any information relative and relatives. Also, Yaesu FT-857 is connected to a computer, which allows you to take fresh weather maps, spaces, exchange emails and small files and photos. The computer connected to the FT-857 is enabled with a Wi-Fi client, so you can control the transceiver and is connected in touch while on a small distance from the car. Even in the car there is a broadband SDR receiver, with which you can quickly scan all the frequency bands, find out who at what frequency works and if necessary to communicate. An example, as SDR works - http://24dx.ru/sdr/all.
But, if, where Makar calves did not chase, you even have no plans to be, then the ballet is all this.
Of course, going to an off-road journey, enjoying the virgin beauty of nature, tasted the spirit of romance and adventurism you will not be the same.
Automotive rates are used on various motor vehicles. They are installed in cars and feed on a source of 12 volts and have an outer antenna. It is one of the main attributes of automotive radio stations. To negotiate, these communication devices have a tangent (outer microphone), which is reported to the main station with a wire. The output power of the radio station can be from 10 to 120 watts.
Where to buy a car radio?
Our online store RADIO SHOP offers a wide range of automotive rates of the best world manufacturers. We can buy car radio in Moscow and other cities of Russia such famous brands like: Alinco, Icom, Motorola, Megajet, Radii, Alan, Yosan and other popular brands.Types of automotive racies
These devices are divided into several types: professional and amateur depending on the frequencies used by them.Professional radiaries work on highlighted special intermediate frequency bands. Mostly such races are employees of motor transport enterprises, employees of public services and private security, Ministry of Emergency Sitvea, emergency workers, etc. Automotive radio stations use such frequencies:
- From 33 to 48.5 MHz and from 57 to 57.5 MHz;
- From 136 to 174 MHz - VHF;
- From 400 to 470 MHz - UHF.
- Si-bi (CB) - civilian range with output power not more than 10 W;
- LPD - on 69 channels with permissible power not more than 0.01 W;
- PMR - on 8 channels with permissible power no more than 0.5 W.
Buying a car radio station on our Internet resource, you can be completely confident in its high quality and long service life. We deliver goods by courier services in Moscow and various motor vehicles in Russia.
The radio station is designed to be installed on the car and works in the amateur range of 144-146 MHz with frequency modulation. The radio station frequency grid coincides with their international division in this range. The stability of the frequency of the radio station is provided by the frequency synthesizer. When testing, it showed very good results. So, on the highway, the connection was stable between two cars at a distance of more than 40 km, and in the conditions of a major city - 15-20 km. The radio station is simple in manufacturing and operation, has small dimensions and does not contain scarce components. The parameters of the radio station are as follows: - the number of channels provided by the synthesizer - 160; - frequency grid step - 12.5 kHz; - frequency modulation with deviation - 3 kHz; - the sensitivity of the radio-0.1 μV; - selectivity but by side channels of reception - 60 dB; - transmitter power - 5 W; - supply voltage - 12V; - dimensions - 200x200x50 mm; - Antenna pin 5/8 wavelength; - There is a noise reducer, a call device, indicating the service life of the nodes; - It is possible to transmit digital information between two single-type radio stations.
The radio station receiver is built according to the superheterodyne scheme with a double frequency conversion. The first intermediate frequency is 10.7 MHz, the second is 465 kHz. The concept of the receiver is shown in Fig. one.
PUC.1A.
PUC.1b.
The antenna signal through an antenna relay located on the transmitter board enters the output 1 receiver board. The input resistance of the board from this entry is 50 ohms. The input circuit, made on the elements LI, C1, is configured to the middle of the 145 MHz band. The high-frequency amplifier is built on the field transistor VT1 type KP350B. The ferrite bead that performs the role of the inductance L2 is found to withdraw the C2 condenser. This allows several decibels to expand the dynamic range of the receiver. On the second shutter of the transistor UHF, the voltage of ARU is incorporated. The signal enhanced by the cascade enters the strip filter, built on elements L3, C9, C10, C11, C12, L4. The connection of the filter contours is close to critical, and therefore the filter has the maximum flat top. The filtered signal with the reel L4 coil enters the mixer performed on the KP350B VT2 transistor. The second shutter of the mixer transistor receives a signal from the frequency synthesizer playing the role of the first heterodyne with frequencies of 133.3 - 135.3 MHz, depending on the selected channel. The L5 coil coils the synthesizer with the mixer input. The load of the mixer is the L6 coil. From the exit of the mixer, the signal at an intermediate frequency equal to 10.7 MHz enters a quartz filter Z1 of the type FP1P1-307-18. Resistors R11, R12 and C18 condensers, C19 serve to match the filter input impedance with the yield of the mixer and the EU input. The filtered signal at an intermediate frequency through the C20 condenser enters the first shutter of the CP350B TP350 type. The second shutter of this transistor also serves the ARU voltage. UPU load is contour
L8, C26. Through the communication coil L9, the OEUs signal enters the DA1 microcircuit that performs the role of the second mixer and the second heterodyne. The heterodyne is built on the pieces of chip and C28, C29, C30, L10, ZQ1 elements. Quartz resonator ZQ 1 - at a frequency of 11.165 kHz. The L10 coil is used to improve the shape of the heterodyne voltage and is configured to the frequency of 11.165 kHz.
The load of the second mixer is the outline L11, C31, configured to the second intermediate frequency equal to 465 kHz. Through the communication coil L12, the signal at a frequency of the second PC enters on the PP1P1-60.03 PP1P1-60.03 piezoceramic filter. Resistors R20, R21 and circuit L13, C32 coordinate the input and output resistance of the filter with the yield of the mixer and the input of the DA2 chip, respectively. The loop L13, C32 is configured to 465 kHz.
After filtering, the signal comes to the Multifunctional DA2 chip type K174HA6, which serves as the second ECU, the frequency detector, the ARU detector. L15 frequency detector reference contour, C46 is configured to a frequency of 465 kHz. The internal temperature meter of the input signal of the DA2 chip is used as an ARU scheme.
The output voltage from its exit 14 will be fed to the transistor VT5 TINA KT315. From it, the ARU signal comes on the second gateway of the UHF VT1 and the amplifier of the first PF VT3. The R22 resistor is used to set the RAC control range. The total range of the ARU system is about 100 dB.
Instead of the R25 resistor, you can enable an S-meter, which can be used as a microammeter by 300 μA, while the resistor R23 you can adjust its sensitivity and to reward it in the future.
The noise cancel is also built on the part of the DA2 chip. The input signal level is used as the input signal level, which is supplied by the Kt315b type transistor, is supplied. The output of the noise reduction system is applied to output 9 of the circuit board.
From the output 7 of the DA2 chip, the low frequency signal enters the volume control mounted on the front panel of the radio station, and from it to the low frequency filter with a slice frequency of 3 kHz, where high-frequency components of noise are significantly reduced. The filter is built on the trazistors VT6, VT7 type Kt315B and VT8 type Kt316e.
From the output of the filter, the low frequency signal comes to the low frequency amplifier, the role of which is performed by the DA3 type K174UN 7 microcircuit. The required amplification of the chip can be adjusted by the R47 resistor. With output 12 chips DA3 reinforced signal
Served through a capacitor C65 pa headset or dynamic head.
The schematic diagram of the transmitting part of the radio station is shown in Fig. 2.
PUC.2
The frequency modulated signal from the frequency synthesizer is fed to the transmitter board 1. Contour L1, SZ set to 145 MHz,. Adjustable amplifier buffer is assembled on the field transistor VT1 type KP3501B. It will serve as a control voltage from the switch of the output power level switch located on the front panel of the radio station. Using this switch, you can jump the output power to 0.5 W. The load of the transistor VT1 serves as the loop L2, C8, configured to the frequency of 145 MHz. From the removal of the coil L2 RF voltage through the C9 capacitor, with which the optimal connection between the cascades is established, enters the second stroke cascade, built on the CT399A type transistor VT2. The transistor's collector circuit includes L3, C14, C15, configured to the middle of the range. On the transistors of the VTZ, VT4, VT5 type Kt920A, KT920B and CT925B, respectively, the line of power amplifiers is ready. Cascades on transistors VT4 and VT5 work in high efficiency mode. The mode of operation of these transistors is defined by stabilizers on diodes VD1 - VD4 and R17 and R20 resistors. When using this scheme for amplifying a single-band cascade signal on VT4 transistors, VT5, you can put a linear strengthening mode with the same resistors.
From the collector of the transistor VT5, the reinforced signal at the operating frequency is supplied to the band-band range on the elements L15 C40, C41, C42, L16, C44, C45, L17, C46, \u200b\u200bC47 and then through the relay K1 switching signal of the antenna, enters the antenna.
It feeds the transmitting portion from 12 in the car battery or from another source.
V. Stasenko, 394029, Voronezh, ul. Leningradskaya, 70-1.
V. Stasenko
RL 4-92
The radio station is made on four printed circuit boards: receiver board, transmitter, synthesizer and general part board. The boards are made of two-sided foil fibercosetolite with a thickness of 1.5 mm, and the foil from the installation side of the elements is maintained completely and removed by the method of the zenkok only around the terminals of the elements not connected to the shared wire. The shared fee is made in the usual way.
All resistors of Types MLT, C2-23, C2-33 are used in the radio station, variable R14 resistor shared SGM-ZGM type, electrolytic capacitors of the K50-29 types on a shared board and K50-35, K50-16 on the rest, on the operating voltage 16 B, other capacitors of Types K10-176, K10-7V, km4, km5, km6, kt. DA1 receiver chips - K174PS1, K174PS4, DA2 - K174H6, DA3 - K174UN7, FP1P1 - 307-18, Z2 type filter - 307-18, Z2 - FP1P1-60.03. Transistors of the VT1 receiver - VT3 type KP350A, VT4 - VT7 - KT315G, VT8 - KT361E, in the transmitter VT1 - KP350A, VT2 - KT399A, VT3 - KT920A. VT4 - CT920B, VT5 - CT925V, in the VT1, VT2 synthesizer - KP303E, VT3 - KP350A, VT4 - VT6 - KT315G, in the total part - VT1 - VT3 - KT315G, LEDs such as AL307BM. Switches in a common part of the type P2K, in the PP8-3 synthesizer (3a), the relay in the RPV 2/7 type transmitter on
voltage 12 V, in the total board K1, K2 type RES-49, K561 series synthesizer chips, headset speaker - 0.25GDSH2, SA1 headset buttons, SA2 - MP3-1, varicaps of the KV105 type synthesizer. The ZQ1 quartz resonator in the receiver may be at frequency of 10.235 MHz or 11,165 MHz. The coils of inductance are mostly frameless. For some coils, fluoroplastic frameworks with the MR100 core are used. The winding data of the receiver coils is shown in Table 1, and the transmitter in Table 2.
Table 1
table 2
The coil of the synthesizer L1 is wound on the ferrite ring from ferrite F600NN size K7x4x2 and has 15 turns of the wire of the PEV-2 with a diameter of 0.25 mm, the coil L2 - on the frame with a diameter of 5 mm from fluoroplast has 4 turns of the PSR wire with a diameter of 1 mm with a tap from 2 turns, Winches with 1 mm increments, the coils L3 and L4 are frameless, have 7 and 2 turns, respectively, the PEV-2 wire with a diameter of 0.6 mm and are located near each other, so that their axes are on the same line.
The Filter Filter Coil L1 is wound on two ferrite rings, folded together and wrapped with fluoroplastic ribbon from ferrite F2000NM sizes of K30X20x6. It has 25 turns of an isolated wire in chlorvinyl insulation of the NV type with a cross section of 1.5 mm.
The radio station is mounted in the body with a size of 200x200x50 mm, made of duralumin. The case consists of chassis, upper and bottom covers. The rear wall of the case is simultaneously the radiator of powerful transistor transistors. She has ribs. On the rear wall of the case there is an antenna connector and the power cord is displayed through the hole. The transmitter board is located at the rear wall, the shared board - at the front panel, and the receiver and the synthesizer board - in the middle part of the case one above the other. The case is painted black and has a modern design. The appropriate radio station controls are derived to the front panel. As a headset, a converted headset from radio stations, similar to those used by railway workers.
The radio station setting assumes the presence of certain skills in a radio ample, because This device, let's say, not for the first repetition of such structures, and the apparent simplicity of its circuits can turn into disappointment during the configuration.
The following devices are needed to configure: C1 - 79 oscilloscope or a similar, VHF-generator with frequency modulation, highlighted meter, tester, sound generator, amplitude-frequency characteristics of type XI-42 and preferably calorimetric power meter, as well as an industrial antenna equivalent Type "Pear" by 50 ohms.
It is desirable to configure each fee to the overall assembly of the radio station separately. The setting can be started from any part, for example, from the receiver.
After checking the installation and making sure the lack of short circuits between the boards are powered by power, after connecting the dynamic head with a resistance of 4 ohms. From the audio generator, a signal with a frequency of 1 kHz and an amplitude of 5 mV on the output 5 of the board, and the ONLC output power must be at least 3 W. Next, check the frequency response of the filter at the input of the UNG, its strip must be within 300 Hz - 3.3 kHz. In this case, the voltage on the dynamic head should not exceed 3.5 V in the entire frequency range.
Then adjust the amplifiers of the first inverter and the second mixer, as well as the second ECS and the frequency detector.
A voltage with a frequency of 465 kHz and a frequency amplitude of 1 mV, modulated in frequency, with the deviation of 3 kHz to the output 18 of the DA2 chip and rotating the cores of the coils L13 and L14, adjust them to the maximum readings of the Millivoltmeter connected parallel to the dynamic head. It is advisable to check the voltage form at the ONLC outlet, it should be sinusoidal. Then the voltage with a frequency of 10.7 MHz and the frequency modulation with the deviation of 3 kHz is a level of 100 μV to the C17 condenser and repeat the same actions by adjusting the outline L8, C26 to the resonance. The contour in the heterodyne of the second mixer of the DA1 chip is adjusted for the best form of voltage and the greatest amplitude, controlling them according to the oscilloscope.
Then adjust the high-frequency part. At the output 3 of the receiver board, the voltage of the level of 400 mV and the frequency in the range of 133.3-135.3 MHz, and on the receiver input - with a frequency in the range of 144-146 MHz and the level of 10 mV to 1 μV. Customize the contour with trimmed capacitors and stretching and compression of turns of coils. Condensants with 18 and C19 achieve the coordination of the Z1 filter at the entrance and exit. It is advisable to check the frequency response of the high-frequency part of the instrument of X1-42. A configured receiver sensitivity should be within 0.1 - 0.2 μV. It must be remembered that in amateur conditions to measure the sensitivity above 0.5 μV is generally problematic and therefore it is necessary to be confident when it is measured in the absence of false measurements.
Then proceed to setting the synthesizer. The digital part usually begins to work immediately and the settings do not require when properly installed.
Running the FAPR varicap control circuit and submitting a voltage of the order of 3 V, adjust the C10 capacitor generator on the VT1 transistor to a frequency of 145 MHz with an open contact K1.1, and with a closed - at a frequency of 134.3 MHz capacitor C9. Next, configure the buffer amplifier on the transistor VT3 capacitor C20 to the frequency of 145 MHz for the transmission mode and the frequency of 134.3 MHz - CONDENSER C18 for the reception mode. In this case, the voltage at the output 3 of the board of the synthesizer should be about 400 mV.
When applying for 1, the voltage synthesizer of 1 kHz and an amplitude of 15 mV, the frequency deviation should be about 3 kHz. Since this parameter in amateur conditions is quite problematic, then control is desirable to conduct on the receiver or by selective voltmeter. Restoring the varicap management circuit, achieve a clear PLG capture when switching the channel number and when switching from acceptance to transmit further adjustment of the corresponding adjustment elements. If you need, you can pick up the elements of the filter C30, R20, C1 in the varicap control circuit. On this, the frequency synthesizer setting ends.
Then proceed to setting up the transmitting part of the radio station. Caringly checking the installation, supply voltage to the conclusions 4 and 5 of the board. The output of the transmitter is connected by an antenna equivalent. As an equivalent, it is not recommended to use parallel to the enabled resistors, because They have a rather large inductance of conclusions. After supplying the supply voltage, the trimms of transistors VT4 - 50 mA and VT5 - 0.1 A. Such currents will correspond to the C mode. To increase the linearity, these currents can be increased before receiving
Submitting a voltage with a frequency of 145 MHz and an amplitude of 100 mV to the output 1 of the board and consistently adjusting the contour coils with stretching and compression of turns, setting the appropriate connection between the cascades using trimmed capacitors, achieve an output power on an antenna equivalent of about 15 W. All contours are undesirable to configure one frequency, as in this case the transmitter can be excited, it is desirable to upset relative to each other a little bit and the other side so that the top of the frequency response of the transmitter was as flat as possible. It is best possible using a frequency characteristic meter, such as XI-42 or a similar one, if there is a radio amateur at the disposal.
Then, changing the voltage on the output 3 of the board in the range of 0.2 - 2 V, control the change in the output power of the transmitter in the range of 0.2 - 15 W. On this, the transmitter setting ends.
Produce a complete assembly of the radio station in the case and perform the installation of booties.
Having setting the headset to the "Transmission" mode and pronounced a long "a" microphone, measure the voltage to output 5 shared fees, it should be about 0.8 V. In the transmission mode R11, you set the 0.5 W output power for the SA2 switch mode "Malaya Power", and a resistor R 12 is a power of 15 W or any other power for the "Full Power" mode.
Then proceed to the manufacture of antenna. From the quality of its manufacture and configuration, those ranges are largely dependent on which communication between the same type of radio stations will be possible.
The antenna sketch is shown in Fig. 1. The antenna consists of a housing where the magnet is located for its fastening on the roof of the car and the extensive coil. You can use a ring magnet from a fairly powerful dynamic head as a magnet. The housing is made of brass and from below the felt is saved to prevent scratches on the surface of the car and increasing the friction coefficient.
The extension coil is wound with a silver-free wire with a diameter of 3 mm and has 4 turns with a diameter of 30 mm, stretched for a length of 40 mm. In the upper part of the case is a insulator, where the vibrator is installed, made of a brass tube or another material of 1180 mm. The coaxial cable is falling in a residential to the coil, and braid to the housing. It is necessary to ensure that the magnet has an electrical contact with the housing throughout the perimeter. This can be performed using petals. From the housing, the cable is displayed into the hole in the side wall. The cable should be a wave resistance of 50 ohms.
Customize the antenna as follows. Connect it to the radio station. The radio station includes 0.5 W output power and transferred to transmission mode. Control the radiation of the antenna on the indicator of the field strength indicator by setting it at a distance of 8 - 10 meters from the antenna and achieve its maximum testimony.
When setting up the antenna, you need to install the car location where it will be during operation and mark it. The setting is tensile and compression of the coil's turns, while the frequency of the radio station must be 145 MHz. If the radio amateler has a KSVN meter, then the antenna setting and its matching with the feeder can be made more accurately.
On this, the radio station setting ends. The radio station was tested in different climatic zones, showed good results and unpretentiousness in service. The author request to all who will repeat this design, report on the results achieved and its revisions.
TYT TH9800 - a powerful car radio station operating in four bands: 27 MHz, 50 MHz, 144 MHz, 430 MHz.
It works on Sibi frequencies, in VHF ranges, and also allows you to listen to the airmader.
I will add only small comments:
The tangent is really very convenient unlike other Chinese crafts. There is a disconnected backlight and key lock.
P1 - P4 keys functions can be changed to others that you most often use.
The station has a double listening feature:
Starts by pressing and holding Hm.
Once in 5 seconds checks the priority channel on activity.
The priority channel is only channel number 1 (for this reason the first channel cannot be removed from the memory).
On both receivers is simultaneously not included.
Dual listening function + second receiver allows you to follow at once in 3 frequencies without scanning.
The second receiver can be turned off by pressing the left volume control. In this case, instead of the frequency of the second receiver, the supply voltage will be shown.
Accessories
Included already have:
1. Cable for remote front panel installation
2. Kit for mounting the front panel separately from the radio station
3. Bracket fastening the body of the radio station in the car
Especially for such radio stations, the Chinese began to produce four-range antennas
In Chirp added full support TH-9800!
Chirp can also open and edit.dat firmware files created in Chinese th-9800 version 2.0.5
Standard Supplies from the seller Zastone:
1 x TH-9800 Mobile Transceiver
1 x Microphone.
1 x Mobile Mounting Bracket
1 x DC POWER CORD WITH FUSE
2 x Spare Fuse 15 A
1 x Microphone Clip
1 x Screw Sets
1 x Remote Front Panel Bracket
1 x English Operating MANUAL
1 x Extension Cable
Pros:
1. Excellent price and quality ratio! For the money (less than $ 300) there is simply no analogs. Wouxun KG-UV950P \u200b\u200bis more expensive, and Yaesu 8900 almost $ 500 and at the same time it does not open at Sibi frequency.2. On 27 MHz power more than Wouxun KG-UV950P. 50W vs. ~ 9W (Maximum power depends on supply voltage. To get 50Ws need to feed the station 13-14B)
3. Full duplex + crossband that allows you to organize a mobile repeater somewhere in the forest, thereby increasing the area of \u200b\u200bthe action of portable radio stations;
4. Many, very many memory channels (800).
5. Many convenient functions of which are not in other Chinese stations. What is not surprising, because they are borrowed from Yaesu 8900.
6. Good sensitivity and modulation for transmission. Sensitivity to 27 MHz is much better than in cheap Sibi stations.
7. There is a step for the PMR and the Aviadpass.
8. Compatible with the Yaesu Arts system (this feature is also in ZASTONE ZT-2R). ARTS is a function of informing subscribers that they are within the reach of radio communications. The radio stations constantly polish each other with special parcels and if the parcels do not receive confirmation, it is considered that the radio station has come out of the radio abuse zone and can no longer be contacted with it.
Minuses:
1. Only one antenna connector. To connect two separate antennas to 27 MHz and 144/430 MHz, you need a HF / UHF duplexer, such as Opek DU-520A or CF-360B Duplexer 1.3-30 MHz / 49-470MHz. Worth $ 50-60.2. When scanning, when the station finds a signal, it makes a short squeak before opening the noise picer.
Not only, because of this delay, the beginning of the transfer is not heard, so also the squeak of this rather loud and its volume is not regulated anywhere.
Update: You can disable it only through the Chirp (twist the sound of the pickel in zero Volume \u003d 0)
3. In the stations of early revisions there are loud cotton speakers when closing a noise-lifter (when the station finishes receiving the useful signal and closes with noise). Fixed via software (similar to clause 2, set VOLUME \u003d 0).
4. When receiving on one receiver and at the same time on the second receiver you switch the channels, the sound in the first briefly interrupted with each rush of the vocoder. In 1407, it was not fixed.
By and large, this station works at the reception and transmission of Als in 6 different ranges:
1. 27 MHz - SI BB (Civil Range)
2. 28 MHz - Radio Digital Range
3. 50 MHz - the Radio Range (not allowed in all countries)
4. 144 MHz - Radio Range
5. 430 MHz - Radio Digital Range
6. Deceptible VHF Ranges: PMR, LPD and FRS / GMRS (the latter is only allowed in America)
Issued from comments:
What is useful to Si-bi in the passenger car on the track?
super_shurik1. You will be warned about all "ambushes" on the road - these are traffic cops in the bushes, cameras on dividing, etc.
2. In the course of the road situation - congestion, traffic jams, repair, idiots on the side ...
3. At night (I always just traveling) Dalnoboev negotiations will not be allowed to fall asleep :) (really helps)
4. If assistance is needed - it is easier to call on the radio, few people stop at night because of the accident.
Loxly.
In general, the presence of a walkie-talkie in the car makes it possible to coordinate your actions with other participants in the movement.
The station is also for sale (on Alikexpress they are ~ $ 275).
If you follow the alikexpress, you can get per share and buy a station in about 220-240 bucks. (Just do not forget to clarify the revision. Our choice is 1407 or newer)
HH-9900 review from Altai-Boltai.ru forum
The antenna is four bands, oddly enough. At the top of the (Sibishnyh) replaced the pin for longer. Tests spent from the shore of the lake in the soupe of the log, on 2m and 70cm with Barnaul talked with a bang! Small repka opened in time, the Aboltus took normally. Novosibirsk track, negotiations of Dalnoboev heard well. Microbovets contacted the shore, he folded from the Zarinskaya route to the lake (about 3-5km) took me without distortion, on the way back, they communicated normally, near Novoaltaisk switched to 26.825 with the same success opened a large river.
The disadvantage of the antenna consider her stiffness, it is weak and considering that it consists of three parts, I think that it will not last long, it will break. Over the way, it flew three times with a magnet from the roof, not from the wind, taped behind the bushes. I think to acquire a duplexer and use two antennas: lemmas turbocharged and two-channel, they are more flexible.
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