Radiois a wireless device that provides communication by duty. They have antennas that allow them to communicate. It operates at certain frequency ranges. Radios that communicate must be in the same frequency range to communicate. The radio can also be described as a transceiver radio. Without the need for cables, communication is provided through radio signals. Slightly different from the actual radio receivers, the device also has the ability to broadcast. Therefore, in some countries, it is expressed as a two-way radio.
The radio device works in the form of the other station being in listening mode when one station is sending, this is the general principle of operation. This event is called simplex communication, in which both stations must be at the same frequency. The principle of two stations speaking at the same time is a system based on different frequencies and is called duplex communication.
Invention of the Radio
The fundamental development of radio products manifests itself towards the end of the 19th century. Studies on this subject theoretically began in 1864, were converted into an experimental study in 1888 and the first radio connection was made in 1896. Radio devices, which are a revolutionary work in all areas of social, political, technological, military and so on, have made a profound difference between the past and the future. So much so that the beginning of the 20th century will be unlike the past in this respect. These communication opportunities, which were impossible to even dream of before, provided great convenience for all mankind in the 20th century and later, and became a solid and undeniable stepping stone for advancing civilization.
In order to mention the existence of a radio communication, at least two devices with identical technical characteristics are required that can operate at the same frequencies. Communication occurs when electromagnetic waves that exit the transmitter -position (transmitting) device and spread through the cable and antenna reach the receiving device (listening) via the antenna and cable of the receiving device.
What is An Unlicensed Radio?
Unlicensed Radio, as its name suggests, are radio devices or systems that can be purchased and used without any license or annual payment. PMR 446 radios are widely used. PMR446 radios are produced in 2 different types. Conventional ones include a total of 24 channels, including 8 channels in the frequency range of 446,000 – 446,100 MHz, dPMR Digital PMR radios 8 Channels Conventional and 16 channels digital, especially in city centers where there is heavy use, conventional systems are expected to be replaced by digital unlicensed radios.
PMR446 radios have 500 mW RF output power and are capable of seeing the needs of medium-sized facilities indoors, building structure and metal density in closed areas affect communication distance, in open areas, speaking distances can theoretically reach up to 3-20 Km depending on terrain conditions, there should be no obstacles for 20 Km communication and frequency should not be exposed to any kind of interference. In practice, Hotels, Motels, Resorts, Factories, Security Companies and Mines can use unlicensed systems efficiently, but it would be more accurate to use radio systems that require a license for radio communications that require a lot of security, OKTH solutions provide great convenience in systems requiring professional licenses. KET regulations can be examined for other unlicensed radio systems.
What is PMR?
The word PMR 446 stands for "Private Mobile Radio". In a sense, it's a special portable handheld radio. The number 446, which is usually used next to the word PMR, is because these handheld radios use a certain and limited frequency range (446,000 – 446,100 MHz. These radios are low-power radio devices that can send at permitted frequencies and forces in their country, with relatively short-range access compared to handheld radios used by amateur radio operators, and are only for voice communication.
Is a License Required on PMR Radio?
No, no license is required to use PMR in Turkey. PMRs are used freely in many European countries and are produced in accordance with the european telecommunication standards institute (ETSI 300 296) specifications and are produced in accordance with the specifications of the "T.C in our country. Approved by the Telecommunications Authority". However, although radios used outside Europe (America, Canada, New Zealand, and South Africa) seem to be the same as PMR radios sold in our country, they operate on different frequencies and channels and are prohibited by law from being sold and used in Turkey. All of these radios, which are allowed to be used in Turkey, are PMR-class radios and are legally permitted to import those with a output power of 500 mW. These are limited to models operating in the UHF 446 MHz. frequency band in accordance with the TGM-NGO-001 regulation of the T.C Telecommunications Authority.
PMR Interview Distance
It is not possible to limit the antenna output power, antenna or other features of a radio to the negotiating distance. Many factors such as obstacles, magnetic fields, buildings, hills, viewing angle or height of the horizon change interview parameters. Even the best 0.5W radio has a range of 3-5 km in the city, depending on geographical conditions. You can also talk to your other distant friend at a distance of 20 -30 Km on the out-of-town straight roads. In the city, the distance varies according to the intensity of buildings, frequency pollution and obstacles.
What are Relay Systems? (Relay,Repeater)
VHF are factors that make it difficult, and sometimes impossible, to transmit distance between terrain shapes and/or stations in UHF bands. In such cases, a device called a relay or relay station is rolled out. Basically, a relay device consists of a high-gain antenna, a low-loss antenna cable, a filter unit (duplexer), receiver and transmitter sections, and their control unit. Relay devices with different frequency between receiver and transmitter are broadcast with the help of the filter unit, the signals heard by the receiver are simultaneously reinforced from the transmitter. Especially handheld devices with limited communication distances are the only way to make calls over long distances. Because relay stations are usually positioned as high as possible. In this way, it is also possible for devices that cannot see each other directly to communicate.
The relay station receives the incoming signal from a certain frequency and broadcasts it from another frequency, often more powerful than the handheld device. Devices that will communicate via relay also use these different frequencies for receiving (Rx) and sending (Tx). The only difference is that they use the sending frequency of the relay as the receiving frequency and the receiving frequency of the relay as the sending frequency. In large metropolises, a maximum of 8 relays working in the same channel can be connected to each other and "link" (connected), thus minimizing the problem of "dead zone". Such relay arrangements are called "wide area relays". These features of relay systems cause the communication channel where the relays are located to be preferred first. However, increasing the intensity of communication traffic raises the danger of a relatively long blockage in these systems.
With the elevation of the place where the relay is placed, a wide area of transmission is taken in the correct proportion. The conversation in which the two radio devices have different frequencies and do so without the help of a relay system is called "simplex" vision. Radio calls where sending and listening frequencies are different and conducted with the help of a relay system are called "semiduplex" vision. In Semiduplex and simplex communication, the receiver and transmitter parts of radio devices do not work at the same time. Relay devices are devices that work full duplex.
The sounds between 67 Hz and 250 Hz are controlled by the signals at these frequencies of the receivers of the devices used in radio communication based on the fact that the human ear does not hear.
What are Frequency Logic and Differences?
When planning radio frequencies, two different operating principles are based. The first is the communication of two radios directly over the same frequency. Such negotiations are called simplexes. This type of conversation is limited to the communication range of the devices. Stationary center radios are the furthest, vehicle devices are medium and handheld devices are devices with the shortest range. Although the communication range is normally directly proportional to the current position, it is usually limited to the horizon distance. In some adverse conditions, and especially when handheld radios are used, this range can be reduced to a few kilometers. High positions and open spaces are advantageous. In short, range differences and unreachable points, dead zone type problems are an integral part of radio communication.
The second type of radio communication is communication through transfer stations called relays (English: repeater=repeater). Especially handheld devices with limited communication distances are the only way to make calls over long distances. Because relay stations are usually positioned as high as possible. In this way, it is also possible for devices that cannot see each other directly to communicate. The relay station receives the incoming signal from a certain frequency and broadcasts it from another frequency, often more powerful than the handheld device. Devices that will communicate via relay also use these different frequencies for receiving (Rx) and sending (Tx). The only difference is that they use the sending frequency of the relay as the receiving frequency and the receiving frequency of the relay as the sending frequency.
What is Amateur Radio?
Amateur radio operator is the name given to people who communicate with their own governments with licenses, domestically and abroad, using any of the permitted modulation types from one of the frequency bands allocated to them, and who do so as a hobby and do not benefit from it at all. For amateur radio, it is mandatory to obtain a certificate, just as with driver's licenses. This is due to the need to have a certain knowledge in order to operate an amateur radio station. In order to become an amateur radio operator, it is necessary to have knowledge about various subjects such as basic electronics, station operating information, laws and regulations. One of the things that the amateur radio operator should know best is what to do in a natural disaster and extraordinary situations. Of course, amateur radio doesn't just end there.
Why would I want to be an amateur radio operator?
If you become an amateur radio operator, you can have excellent and uninterrupted conversations with other amateurs over a frequency or through repetitive stations. You can communicate between computers over long distances and communicate without embossing your phone bill (e.g. simultaneous voice-image-correspondence with other amateur radio operators in all countries of the world from Radio internet switching stations with facilities such as Package Radio, APRS, SSTV, Ekolink). It's also possible to contact amateur radio operators via orbiting satellites.
How Hard Is It to Get an Amateur Radio License?
Actually, it's not that hard. In Turkey, two classes (A and B) are tested for amateur radio. Of these, class B documents are those that do not need morse knowledge and can be obtained with fewer points. It is possible to obtain a B-class certificate provided that you are successful in 3 written, multiple choice exams that you will take from electrical-electronics, law-regulation and station management. To study for the exam, solving the questions that have come out is a very efficient method.
So how do I get a Class A Amateur Certificate?
For this, you need to score above what is required for class B, and you also need to know morse. The easiest way to learn Walrus are morse-teaching programs that you can find in many FTP areas. An important advantage of a class A radio license is that you can talk to various people around the world using hf (high frequency), and you cannot use HF frequencies on your own station with a class B document.
Where should I apply for the exam?
Exams are held twice a year by the General Directorate of Coastal Safety, and for applicants, it is enough to fill out a forum via e-government, and small amounts of tuition fees are paid.
What Should My First Radio Be Like?
If you want to start with a Class B document, it is possible to connect with other amateur radio operators in all major cities of Turkey via simplex or repeaters with a Vhf handheld radio that you can buy; however, it may be more convenient to consider the future and take a device that works in VHF-UHF bands called Dual-Bands at a slightly higher cost. VHF and UHF are working in many parts of Turkey.
Another interesting and new technology-intertwined topic is Packet-Radio and APRS. Using a radio modem, you can communicate within the worldwide amateur radio network. There are several ways to do this, one of which is to communicate with others via another Amateur Radio BBS that you can reach via HF (simultaneous chat, e-mail, file transfer, etc.). ). Another way is to use internet doors.