The article introduces the principles of making a homemade home antenna for receiving channels of digital broadcasting and the main models of factory-made indoor antennas. The home television antenna receives a signal in the immediate vicinity of the transmitting tower, but on the first floor, nearby houses and trees will prevent the reception of channels.
Do-it-yourself home antenna for digital television
Digital television channels transmit multiplexed channels - many-many television programs are being put on one frequency and this is transmitted simultaneously. The first multiplex broadcasts on 30 and 34 channels( 546 and 578 MHz) and on December 13, 2013 in Moscow, the frequency of 24 channels( 498 MHz) earned the second multiplex.
The list of television programs is constantly updated and updated. If the tower or repeater is nearby, it makes sense to try to receive the channels of a home antenna for digital television. Of course, for this you will have to acquire a special TV tuner( receiver) - the device decodes the signal and transmits it to the TV.
Antenna is made of 75 Ohm wire. For example, it could be cables like:
- SAT 50;
- SAT 703;
- SAT 752;
- DG 113;
- CATV 11 and other cable brands.
To manufacture the antenna you need:
- A half meter cable cut.
- F-connector for coaxial cable.
- Adapter with F-connector to TV tuner.
Working with a cable is simple enough with a sharp knife. A simple equation - the speed of light divided by the frequency of the multiplex - will help calculate the three wavelengths of multiplexes. The result should be three lengths full of about half a meter and up. The value of each length is divided by 4, sinceWe are preparing a quarter-wave vibrator - a television antenna for digital television. Example:
The second multiplex is broadcasting at 498 MHz. We find the wavelength = 300/498 = 0.6 m. The rounded result( 60) is divided by 4, we get the length of the antenna( 15 cm.).
The process of self-creating a home antenna for television
One end of the 20-cm cable, cutting the insulation 2 cm from the edge, we equip the F-connector. Shielding layer downward, then removing the lavsan layer and the central insulation layer. Gently twist the end of the coaxial cable F-connector.
Mark the blank with a pencil just above the end of the connector - a cross bar should remain on the insulation. Take a ruler and measure out 15 cm( for the second multiplex).We mark the second mark with a line, take a knife or pliers and carefully cut off the cable at the second mark. Antenna television home is ready. Remove the shielding layer and the outer shell of the insulation between the first and second mark. For a confident reception of the signal we bend the F-connector 90 degrees.
Attach the adapter to the F-connector and plug it into the TV tuner. Rotate the antenna parallel to the semi - polarization of the multiplexes. Try the signal strength in the software of the TV or TV tuner.
Note. The polarization of the transmission of a television signal is traditionally horizontal, vertical is used in the radio. The exception is satellite broadcasting - Tricolor transmits in circular polarization - channels catch parabolic antennas.
From April 2014, a third multiplex is launched in Moscow, and the programs there are already selected on the basis of tenders. The third multiplex is going to be broadcast in both linear and horizontal polarization.
Antenna for digital television MTS
Today everyone wants to watch television in digital, while MTS has a network of towers around the country. The company offers to purchase set-top boxes that allow you to view TV channels. The promotional offer provides the first year with a subscription fee of 190 rubles per month( further payment will increase to 250 rubles).Manufacturers of digital tuners claim that a similar digital tuner will be able to receive more than 150 channels, including high-definition television( HDTV) - a real celebration of brightness and clarity for owners of large plasma and LCD panels. Ordering such a console is easy.
- We leave a request on the site,
- We are waiting for a callback,
- We accept the master on a visit.
Such an order is provided for all regions, however, when a professional installer at a house in the periphery leaves the scene, doubts arise - you will have to call and clarify.
MTS equipment, in general, receives most of the Moscow multiplex channels, this impression remains after reading the SD set-top boxes( entry-level devices — provider classification).Also, the structural components of a typical device are an HD set-top box and a CAM module. The polarization of the MTS signal for each region is different - call the service center and check. There is a small chance that home-made home antennas for the TV will work in this case as well( linear horizontal polarization).
The provider’s official website, which contains a section for solving problems of digital television, which describes all existing equipment error codes, will help to understand whether a home-made digital antenna works with MTS equipment.
Purchased television antennas for TV
Television( not only digital) broadcasts in the meter and decimeter bands. The approximate upper bound is around 1 GHz. Today, all television is switching to the DVB-T standard( terrestrial broadcasting) - the rest of the bands have lost their relevance. And it is also invented:
- DVB - C( cable broadcasting);
- DVB-S( satellite broadcasting);
- DVB - H( broadcasting on mobile communication).
The given frequencies fit into the UHF range( decimeter waves).For the purchase of a suitable antenna, the reception frequency is the main factor. Analog TV channels are scattered across different bands, some instances of receivers catch and radio( FM - band).Let's see how to choose a home antenna. Example:
We look and see the Rolsen RDA-60 home antenna in the online store. The product description speaks of the antenna’s ability to receive both analog and digital frequencies. When we get acquainted with the instruction, we see the reception bands - UHF( 300 MHz - 1 GHz), VHF( 30 MHz - 300 MHz), FM( 87.5 - 108 MHz, included in the VHF).The last specified connector exists for receiving a radio signal. This means that the antenna reception spectrum is trimmed( 87.5 - 230, 470 - 862 MHz) - enough for all standards.
In appearance this is the usual vertical pin principle of operation remains unclear. The description speaks about the possibility of changing the angle of inclination, it expands the range of reception. But on the Rolsen website this is called a novelty, the price of the device is about 500 rubles, the country of origin is China.
From the above example, we see that any indoor antenna has a certain reception range. After purchase, the product will need to be properly installed. Digital television has horizontal linear polarization, therefore, the antenna should be placed horizontally, or tilted - only then the antenna will begin to correctly and clearly receive digital signals.
TV indoor antennas will catch the signal, provided that the tower is located nearby. A special antenna amplifier may not always fix the situation. Re-amplification of the signal will manifest itself as a double image and red-white interference. When cable television was being used, signal oversampling was a real scourge of provider networks.
Well, that’s what home antennas are for TV.In fact, there are only two types of them, self-made and purchased First will be pleased by the fact that they can demonstrate to our second half that we can do something with our own hands, the second will have great potential, in particular, they are calculated for several ranges.