Diagram of a receiver radio signal amplifier for a car radio. Do-it-yourself antenna amplifier: a do-it-yourself master class for making a universal device. Overview of some models of car antenna amplifiers

21.10.2020 Safety

The radio signal amplifier for the car radio improves reception quality in difficult conditions. This device is used with both radios and TVs.

When You Need an Amplifier

A car antenna booster is needed when the signal strength is insufficient to comfortably listen to FM radio in the car. This most often occurs in small towns, remote from large radio stations or powerful repeaters.

When receiving on a passive auto-antenna for a radio tape recorder while the vehicle is moving in adverse conditions, noises, clicks occur that interfere with listening to music and speech programs. If the car enters an area with an excessively low signal, then the interference is permanent, blocking the radio transmission.

What affects the signal level

The level and propagation of the signal in the FM band is affected by:

uneven terrain;
high-rise buildings built of reinforced concrete;
atmospheric phenomena;
sources of interference installed in the machine;
distance from the transmitter to the car's antenna.

What to choose

When choosing an antenna amplifier, you should pay attention to various parameters. This device should have a wide bandwidth and a flat frequency response. Also, a high-quality antenna amplifier has a low signal-to-noise ratio. To ensure stable reception and protection from interference, it is recommended to install the amplifier closer to the antenna. If you install it next to the radio, then the level of interference generated by automotive electrical equipment will increase.

The device must be accompanied by instructions and all accompanying documentation. It should be borne in mind that this device should not be used together with an active antenna. Because of this, the reception will greatly deteriorate, since the car radio will catch all the ethereal garbage. And during the tuning of the receiver, the signals of strong stations with distorted and noisy sound will be constantly listened to.

domestic manufacturer

Among the amplifiers for the car radio, released in Russia, the device called "Triad-304 - Dalnoboy" is most in demand. It improves reception at a distance of 60 to 120 km from the radio station, works in all required ranges, has a light indication of the presence of power.

Another feature is the city-highway switch, which is used to decrease or increase sensitivity depending on radio reception conditions.

The connecting cable is long enough so that the radio amplifier can be installed close to the antenna.

Other advantages include low price, high reliability and sensitivity.

foreign manufacturer

The most popular foreign antenna amplifier is the Prology TFB-100. It differs in that it amplifies both analog and digital radio and TV signals with the same quality.

Several antennas can be connected to it, which will improve the quality and stability of the signal at the edge of the stable reception area. This accessory will be useful for those who have a multimedia system with a TV in their car.

How to DIY

An antenna amplifier for a car audio system can also be made independently. This device is built according to the classical scheme. A high-frequency filter is placed at the input, assembled according to the P-circuit and providing an input impedance of 75 ohms. It consists of a coil connected in series and 2 27pF capacitors connected in parallel. To protect audio equipment from accidental high voltage, a low-pass filter is placed after the HPF in a T-circuit.

1 stage, built on a KT 368 AM transistor or its equivalent, gives a gain of 15 dB in the FM band. Resistors can more finely tune the characteristics of an electronic device. Plus power is supplied to the collector of the semiconductor, minus to the emitter.

To stabilize and filter the current, a Zener diode D 814 G or its equivalent and a capacitor with a capacity of at least 100 μF are connected in parallel with the power input.

The number of stages is determined by the required gain. The connection between them, as well as the input of the car radio, is capacitive. You can assemble an amplifier for a car radio both from a radio designer and from existing parts. A short piece is attached to the output of the device coaxial cable with a suitable plug. The whole structure is placed in a plastic or tin case of the desired size.

How to install and connect

Installing and connecting the amplifier will not cause any particular difficulties. First, you need to remove the plug of the external external car antenna from the radio. Then the amplifier is fixed in a suitable place. If it is equipped with a city-highway switch, then for ease of control, the device is installed on the instrument panel near the radio or in the glove box of the car.

The output plug of the amplifier is inserted into the antenna socket of the radio, and the antenna plug is inserted into the input connector. After that, power is connected to it. To do this, the wire coming from the amplifier is connected to the blue wire of the radio with a white stripe, along which the power plus goes.

The minus to the amplifier is supplied through the side contact of the socket and the screen sheath of the connecting cable. When the signal is strong, the reception quality of the amplified antenna can be improved by folding the telescopic rod or bending the flexible one. It should be borne in mind that the receiving dipole should not come into contact with the car body.

Drivers are accustomed to the comfort in the car during the journey, listening to music thanks to the radio. But sometimes inexpensive car radios do not pick up radio stations outside the city. The radio signal amplifier for the car radio will help to fix this problem. The article discusses these devices, types, gives recommendations for choosing.

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The purpose of the amplifier

Modern ones are equipped with good functionality, but at the same time, many of them cannot provide reliable reception for the radio. This is especially evident outside the city, when the signal strength weakens so that the radio does not work. How so that there was a confident reception of a signal? The way out of this situation is an antenna amplifier (adapter). Its main purpose is to ensure reliable and uninterrupted reception of radio waves of different ranges without interference in different directions, that is, they must amplify the signal.

Properties of a quality device

A high-quality antenna amplifier for a car radio should have the following characteristics:

the operation of the device must be carried out in a wide range, its power must cover the entire range of radio waves;
the operation of the device should not depend on temperature and power;
there should be uniform amplitude and frequency characteristics;
low noise;
the signal gain should be at least 15-25 decibels.

It is preferable to buy devices mounted directly on the antenna. If the adapter is placed near the base of the antenna, there may be strong interference and noise from electrical equipment, which will reduce the gain of the radio signal and affect the sound quality (video by ChipiDip).

Criterias of choice

All devices designed to enhance the radio signal must comply with the requirements for communication systems.

When choosing an adapter model, consider the following factors:

the device must cover the required frequency range;
the gain must be above 15-25 decibels;
amplitude and frequency characteristics should be as uniform as possible;
must be high for overload protection dynamic range.

The gain of the radio wave should be high enough to improve reception quality, but should not be too high, as overloading can damage the device.

Popular Models

The market offers a wide range of models of foreign and domestic production. Among domestic brands, Triada products are popular. For example, the Triada-304 Dalnoboy model has the function of turning off the device in the presence of a confident signal. Thanks to the radio device in the car, it works in the range of the following frequencies: VHF, FM and AM. Among the advantages are small cost, optimal functionality, good quality.

Among foreign brands, Prology can be noted. An example is the TFB-100 model, which has the function of amplifying radio radio signals of both digital and analog ranges with the same accuracy. In addition, this device can work simultaneously with multiple antennas.

You can make an adapter with your own hands. Master KIT provides such an opportunity to radio amateurs by releasing kits from which you can assemble a complete device for amplifying radio signals using a two-stage circuit.

Components must be selected so as to provide maximum amplitude-frequency characteristics.

If you use 2SC2926 bipolar transistors with a frequency of less than 1 GHz in instrument circuits, you can reduce the noise level that is created by the adapter itself. To power the adapter, 12 V is enough. The board is connected to the ANT output of the radio. Thus, the amplifier will start working after turning on the radio. Installing the antenna amplifier does not take much time, so it can be done by hand.

Issue price

Buying a radio signal amplifier for a car radio in our time is not a problem. In addition, such a product is quite accessible to a wide range of buyers. The price range varies from 100 to 1000 rubles. Therefore, for relatively little money, you can be content with listening to the radio without fear of interference and weak signal.

Car antennas have long been considered an everyday accessory, but such equipment often breaks down, often it is simply stolen. Factory models are quite expensive, and it is often problematic to find the right one. However, you can make auto antennas for the radio with your own hands. The process is simple, but requires some professional skills.

The range of devices in stores is very large. According to the purpose, this technique is divided into the following types:

Active antennas for the car radio when the signal is received along with the built-in amplifier. They are considered very powerful. Great for picking up signals over long distances.
passive models. They work without amplifiers. Considered simpler, they are much easier to make yourself. Such devices are just recommended to be installed if car radios are used only in the vicinity of the city.

Antennas are classified according to the installation method. Distinguish between internal and external antennas:

Internal. They are mounted in car interiors. This installation method is suitable for active models.
External. They are located outside the car bodies. This installation is more suitable for passive devices. At the same time, the low power of the technique is somehow compensated.

To make an antenna for a car radio with your own hands, you need to take into account the principles of operation of the signal catcher, determine the length of the device, its location, and the degree of complexity of the entire structure.

Conventional car antennas are quarter-wave vibrators that are grounded to car bodies. Such devices can only be mounted vertically, and reach a length of 2.5 m. For antennas of standard car radios, these parameters are considered redundant.

That is why, to replace obsolete overall devices, self-made external antennas for car radios are used. To hear stable radio signals in the popular range, it is enough to use pin devices with a length of 10 to 20 cm.

In addition to significant cost savings, there are a number of other advantages in using this technique. The following advantages stand out:

A self-made design can be customized to fit perfectly different models cars.
There will be no problem with the installation height for receiving radio signals.
Installing a homemade device is much easier than factory counterparts.
It is possible to improve the quality of signal reception with the correct production of the installation, in contrast to the use of purchased antennas.

It is worth noting that you can start self-designing if you have skills in working with electrical engineering, otherwise it is better to use the services of professionals or use store counterparts.

You can make both inactive and active (with an amplifier) devices with your own hands. The production technology consists of several stages:

preparing the necessary tools;
direct assembly;
fastening to the machine body;
connections.

Assembling different types of antennas for a radio tape recorder with your own hands differs significantly even in the selection of the necessary tools.

Passive antennas without an amplifier are considered to be quite simple in their design. To create such a device, you will need:

copper wire (diameter from 1.5-2 mm);
quality nut;
a good file;
screwdriver;
thermal glue (can be replaced with heat shrink tubing);
screw (diameter M5);
lock-nut.

Assembly is carried out in stages. For this:

To give an aesthetic appearance to the installation, a film is glued on it, treated with a primer, and painted. The passive device is ready.

Creating an Active Fixture View

A feature of this technique is the presence of equipment that enhances signal reception. When creating internal active installations, frame structures are used. This requires the following tools:

copper wire, always with insulation (diameter - 2 mm);
home amplifier (a TV device will do);
high-quality soldering iron;
connector that is suitable for the radio;
good cutters;
glue.

An amplifier case designed for a conventional home antenna is often used as the basic basis for the device. Solder a wire to it, which, in turn, will be connected to the radio. This is necessary for the amplifier to receive and transmit signals.

An antenna plug is connected to the socket, a connector is mounted on the other end of the wire. The power cable for the amplifier in car radios is considered a control cable, it is colored blue.

An active type receiver is mounted on the roof of the car so that signals are well received. To do this, two holes are drilled in the body - mounting and auxiliary. The antenna wire is laid along the perimeter of the driver's door, fixing with glue. After installation on the roof of the car, they fix the cable (side) in the rack, carefully connect it to the car radio.

Features of installation and connection

Traditionally, active types of antennas for radio tape recorders are installed on windshields in the upper right corners or behind rear-view mirrors. Passive installations for receiving signals are placed on car bodies, usually mounted on roofs.

Any antenna is mounted only on a clean surface. For installation, use glue or masking tape, bolts, nuts, locknuts for grounding, a drill that is suitable for the diameter of the antenna wire. The mounting site must be degreased with a special cleaner.

Fix the devices with glue or masking tape. After installation, wires are laid from the antenna to the radio. This is done either around the perimeter of car doors or windows, or directly through the cabin through special holes.

There are three wires in the design of an ordinary car antenna:

Most often, the second wire is combined with the third, connecting the power, activate the contact function, the antenna begins to receive a signal.

It is important to choose the right place to install the antenna. A car body can be both a kind of indicator of improving the quality of signal reception, and a hindrance. The best place for fastening is the center of the roof.

Near the catcher should not be foreign objects made of metal. Combined antennas for receiving various communication signals are best purchased ready-made.

The installation must be protected as much as possible from the influence of the external environment so that the contacts do not oxidize and the details of the entire structure do not rust.

Antenna made by hand effective method savings, improving the quality of signal reception, the possibility of technical refinement of the radio in your own car.

Cassette recorders today can only be found in rare cars, but modern cars are equipped with more serious systems that play the role of entire multimedia complexes capable of performing hundreds of different tasks. However, drivers love to listen to the radio and watch TV on the road just as much as ever. Unfortunately, most inexpensive radio tape recorders with good functionality, they stop “catching” radio stations as soon as the motorist leaves the city limits. The sound becomes distorted and jumpy, the picture is out of sync, noise appears. These signs indicate that the signal has become worse and soon you will have to drive along the highway in complete silence.

It’s worth saying right away that even the most advertised brand will not guarantee you a high-quality radio signal. Therefore, if you like to listen to the radio on the road, then buying a more expensive radio will not help. It is better to purchase a tape recorder with an antenna and supplement it with a special amplifier.

Antenna amplifier

You can buy an antenna amplifier for a car radio ready-made or make it yourself. When choosing a model, you need to focus on the following characteristics:

the amplitude-frequency characteristic should be uniform;
the device must operate in a wide range, regardless of temperature and power;
minimum "noise";
the amplifying factor should be about 15-25 decibels. A lower value will not improve reception quality.

It is better to buy amplifiers that can be installed on the antenna itself. If the device is located in the area of the antenna input, this may lead to an increased noise-to-signal ratio, which will undoubtedly affect the sound quality.

Most Popular Amplifier Models

And they are not. An example, an amplifier of "domestic" production "Triad 304". Such an amp costs about 650 rubles. Reviews about this amplifier, let's say right away, are not the best. Judge for yourself what can be good in it if it is empty inside.

Most likely, this miracle, registered under a Russian name, was produced wherever you think ... And there are plenty of such amplifiers.

The Bosch Autofun Pro antenna with a built-in amplifier deserved positive feedback.

Only here lies the catch. Here are the photos for you. One antenna is "left" (left), and the second is the original (right). One catches nothing, and the second caught perfectly for 100 km.

Do-it-yourself antenna amplifier

An antenna amplifier for a car radio is a device that you can make yourself. For this, a classic two-stage circuit with 8 main resistors is used. Elements R1, R2, R4 and R6 in this case will allow you to stabilize changes in the transistor VT1 if at some point there is a power surge or a sharp rise in temperature. All components must be selected so that the maximum characteristic of the amplitude and frequency of the device is provided.

In addition, 2SC2926 bipolar type transistors are often used in amplifiers, at a frequency of less than 1 GHz. This will reduce the noise level from the amplifier itself. All components of a two-stage circuit must be soldered on the board in the correct sequence. After assembly, you need to connect the input of the amplifier to the antenna input, and direct the output to the radio. To do this, use a cable with a resistance of at least 75 ohms. In this case, it is important to observe the polarity.

It is better to organize power with a network with a voltage of 12 volts. After that, you can connect the board made to the radio (ANT output). So, the amplifier will start working as soon as you turn on the car radio.

Curious, you can try to make such an amplifier. How to test, unsubscribe.

In custody

If we talk about which is better - a ready-made antenna amplifier for a car radio or a home-made one, then it is worth noting several advantages of each of the options. The finished device is inexpensive and you only need to connect it. In its turn, homemade device does not require special skills and knowledge, but at the same time allows you to get a clearer signal and reduce interference.

Antenna amplifier for car radio

Antenna amplifier for car radio is designed for better and more confident reception. Recently, inexpensive car radios have been produced, although with good functionality.
Unfortunately, they are not able to provide reliable reception of radio stations. This is especially true for areas far from the city, where there is a signal level, but it is too weak.
For a car radio, the antenna amplifier protrudes into this case, as a device that dramatically increases reception.
If earlier cassette recorders were found all the time, today they can only be seen in vintage cars. Modern car radios are more multimedia complexes equipped with a huge range of options.
Yes, modern equipment does an excellent job with navigation, perfectly plays music from various media, helps the driver to park, etc. But the motorist will always miss the radio or TV on the road - an experienced motorist knows this!

As mentioned above, a modern multimedia center is not capable of providing a good radio signal, especially outside the city. Then you have to purchase an antenna amplifier - a special device that significantly increases the power and quality of the signal.

How to determine if the signal is weak

It is quite easy to do this.
It will be enough to familiarize yourself with the signs of a weak radio or TV signal, which are given below:

Distorted when viewing or listening to sound. Frequent interference;
The list of received stations is drastically reduced;
Image synchronization is lost;
The signal disappears completely;
Instead of a picture, white small dots are visible on the screen, only noise is heard.

Get to know your device

Such an amplifier is specially designed for effective and confident reception of stations. Most motorists who have installed an antenna amplifier in their car note that the signal has doubled, if not more.

Note. The device does not require any special skills to install. Its connection is just a connection of one contact to the head unit, and the other to an external passive dipole.

Almost all modern antenna amplifiers for a car are assembled according to a two-stage scheme, although they may have some differences. But they must necessarily meet the standards of modern communication systems.

Selection Options

Priority attention should be paid to the possibility of installing an amplifier not far from the antenna.

Note. You should be aware that connecting directly next to the input of the car radio, on the one hand, significantly increases the signal level, and on the other hand, it threatens with interference emitted by electrical equipment.

Remember that the operating band must cover the desired frequency range;
The amplitude-frequency characteristic should be as uniform as possible;
As for the gain, it is desirable that it be in the range of 15-25 dB;
With a spread of supply voltages, stable operation should be ensured;
The dynamic range must also be high, which contributes to protection against overloads;
Finally, the noise figure must be much less value signal/noise.

Note. The gain should be given the most attention. The fact is that with its small values, the reception quality cannot be high.
On the other hand, for the city, these figures are quite normal. If this very coefficient is too high, the broadband amplifier may be overloaded, which can lead to its damage.

Imminent factors that affect the signal

Note. Note that the best effect is achieved if the amplifier is connected to an external antenna. Thus, an active rather than a passive dipole is connected. Distance is also important. So, you should not count on high-quality reception if the station (main transmitter) is located at a distance of more than 120 km.

It is worth noting that there are side factors that somehow affect the signal level:

In the city itself, there may be an overamplification of the signal. The manufacturer recommends either turning off the amplifier in the city area or reducing the gain;
It is also not recommended to use the amplifier at the same time as an active antenna. This can lead to the opposite effect: the signal will deteriorate, distortion will appear;
After replacing the head unit, signal reception failures may be noticed. It turns out that the matter may lie in the power supply that was forgotten or could not be connected to the active antenna. Buying a special adapter or making it will immediately solve the problem.