Car owners who spend a long time behind the wheel of their cars, strive to provide maximum comfort themselves and passengers. Such features of comfort include various multimedia systems with TV, video and audio. However, classical antennas poorly perceive the signal from many TV towers.
In such a situation, a car TV antenna made of scrap materials will come to the rescue. If performed correctly, it will significantly amplify the TV signal and provide clear picture and sound.
- 1 Classification of popular antennas
- 2 Independent production of a TV antenna
- 3 Built-in construction
- 4 Outdoor installation
- 5 Correct installation
- 6 Cable connection
- 7 Advantages of a self-made design
Classification of popular antennas
Antennas include quarter-wave vibrators used with matching devices. As the grounding used car body, successfully coping with this role. Most of the schemes necessary for the operation of the device are fully capable of assembling on their own even to a beginner radio amateur. But before you make your own car antenna, you need to consider in what capacity it will use, the type of modulation used, as well as the range of frequencies that the final product must perceive.
There are two main types of antennas:
Additionally, the device can be equipped with any external power source. According to the method of installation can be divided into external and internal devices. In both cases Requires rigid fixation of the device to the car body.
The design of the combined type is also applied. It is classified as an active intra-salon device, having external elements that provide high-quality reception of signals in the decimeter and meter ranges.
You need to know that the antennas for improving the signal are completed not only with amplifiers, but also with special filters that ensure efficient switching with the onboard network.
The operation of a car TV antenna depends on the location of the car, so the device needs regular adjustment to the reception conditions. At a significant distance from the transmitting towers, the car owner can install a satellite TV system in the car.
Independent production of a TV antenna
A significant difference between stationary indoor aerials and car antennas is the mobility of the receiving point for the car. The use of household antennas in such a situation will lead to the emergence of a large number of "blind" zones during vehicle maneuvers. This behavior is based on the polarization of the vertical type.
When operating a common biquadratic frame, the direction of vertical polarization is not a significant factor, since it is located as vertically as possible.
During the manufacture of the antenna for a car at home, you should pay attention to such factors:
- road inspectors should not have to the device any valid claims relating to hull modifications;
- the antenna should easily fit and be mounted in the cabin, without creating problems for driving or discomfort for passengers;
- the signal should be received as steadily as possible at the desired frequencies;
- the device must function with maximum efficiency.
If necessary, the car TV antenna must be dismantled quickly and without problems.
It is not always appropriate to use the classic quarter-wave vibrator for built-in auto-antennas. It may be difficult to manufacture, and it also has significant overall parameters. Problems may arise when fixing a large object.
As a practical design, the following assembly showed itself well. You will need a frame device placed under the rear window seal. It should be understood that this form is slightly different from the classical apparatus operating at 27 MHz. Dimensions are compensated by the presence of a capacitor in the middle part. With him carry out the tuning of the resonance on the desired channels.
It is necessary to take into account with such manipulations that there are several receiving frequencies: 27 MHz, 65 MHz, 28.2 MHz, 68 MHz. For the upper resonance is characterized by the lower range of the broadcast.
The design of the internal antenna is manufactured according to the simplified scheme:
- Used copper conductor MGTF 0.5. It is hidden behind a rubber glass seal. In this case, the upper part is made narrower than the other elements.
- The location of the poles is obliged to contribute, if necessary, to the addition of a wire to a capacitor, as well as the addition of a wire RK-50 for signal removal.
- A 5-25 pF capacitor is mounted on the center of the rear window; it has the maximum vertical connection of both cables.
- Sealing of the wire is done from the end, bitten off in the center by nippers. There should be no breaks at the back end.
Such an antenna is connected to the connectors used for communications equipment.
A TV amplifier of the Polish assembly is usually used for the external construction. Everything can also be collected independently. High-quality signal transmission provides a pair of telescopic antennas. They are usually borrowed from old radios at the dismantling of the radio market.
As the body fit plastic from the amplifier, which is fixed magnetic mount. At the next stage, the system is provided with power. You will need to take the connector from the active antenna and solder the wire into it. After we conduct the cable in such a way that it does not get any problem chafing or clamping, and finally fix it in this position.
Soldered to the connector wire to the output jack, which has a connection to +12 V on the multimedia system. We start the plug into the corresponding "input" of the socket and enjoy a clear image.See also: Anti-skid chains on the wheels with their own hands
The installation process must be approached responsibly to ensure maximum signal quality. The car owner chooses the design himself so that it fits the parameters for the built-in TV.
The advantage of the built-in antenna is maximum protection against external negative effects on the device. As a disadvantage noted the difficulty in dismantling without deformation of the active receiver.
As an alternative, motorists use a mortise design. The main part of the antenna will be inside, and only the receiving rod extends outward.
Installation conditions must be observed:
- Reliable installation and fastening to the car body. In the presence of carbon coating inside the signal will go weak. After installation, the maximum protection of the metallic external elements against possible future corrosion is carried out.
- Protection can be performed with silicone sealant. It is not advisable to apply the winding with tape or putting plastic on the dock. Such procedures provide condensation under the insulation, as well as weakening of the signal.
It is advisable to use high-quality metal coated parts.
The system must use a cable. To do this, it is customary to install a coaxial shielded cable.
You need to know that for the installation should be used one-piece pieces of cable without twisting or adhesions.
First you need to stock up on the bay with a sufficient cable length. Be sure to check the cable for breaks with a tester before using it. The quality of the cable depends on the signal level.
- Step 1. We select the appropriate amplifier
- Step 2. Connect to the cable
- Step 3. Putting the scheme
- Step 4. Install the plugs
- Step 5. Isolate the contacts
- Step 6. We pack in the case
When laying it on the body of the car should follow these rules:
- it is necessary to position the cable to the body of the kA car from the outside as well as inside the car as tightly as possible;
- for an outdoor cable, a minimum length limit is established, since the tan is exposed to a negative external influence;
- the length should allow laying without tension, but with a slight slack;
- Do not allow sharp bends.
In order not to be mistaken with the length, you can preliminarily take measurements with a tailoring meter or a building tape measure.
The advantages of homemade design
Self-made antennas for car TV are unlikely to be able to outrun the expensive factory analogs in quality, however, they will ensure sufficient reception of channels in almost any city or in a country region. You can collect them from scrap items that are offered in any market for used electronics. The cost of the final product will be significantly lower than the price of the average product quality.