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How to make a high mast for TV antenna
Many gardeners there is a problem, as the high-quality reception of TV programs in a country house. Spoilt a good image on the screen in his home town by traveling to the country (where even the TV is not the latest model, probably), they suffer from a sharp reduction in the number of television channels received, and the quality of the image.
A radical solution to the problem of course, can be considered the installation of a satellite dish. And the number of channels - 200 (a foreign language), and the quality is excellent. But satellite TV still does not replace our normal channels and we will look at the standard variant - for the installation of masts Antenna of Television. Normally mast antenna made of high slender tall pines. Their height can reach 10-15 meters! At first, I also wanted to follow the standard way - to use pine. But talking with a neighbor, who is such a mast is refused to the idea. Firstly, on such a serious antenna mast type \ "wave channel \" will not put. \ "Break \" load on the mast rises sharply. Second, thin pine is very flexible. And when the wind is strong, if not break, then it begins to swing quite. What would these fluctuations do not interfere with the reception, we have to put broadly (and hence inefficient antenna). During that fight? And third, as recommended by themselves antenschiki, mast antenna must be metal and grounded. Otherwise, it will need to work effectively to arrange artificial \ "land \". A metal mast and at the same time serve as a lightning rod.
Weighing all \ "for \" and \ "against \" I decided to make a metal mast. The design, of course not discussed - of course on the principle of telescopic. The choice - two types of material. Pipe or rectangular profile. The mast profile has disappeared because the profile is weak at great length on twisting. In addition, it is more expensive and harder.
5 tubes were purchased length of about 3-4 meters each, and those in which the inner diameter matches the external diameter of the thinner tube. So that they could be inserted into each other. There was also acquired television antenna \ "wave channel \" amplifier to the antenna itself. (By the way, the type of Yagi antenna is one of the most effective). Power is required to compensate for attenuation in the coaxial cable and, in general, signal amplification. It was supposed to trigger long enough, about 20 meters. A to the television station - generally about 100 km.
The thickest tube (I have 55 mm diameter) was acquired from the \ "tail \" 1, 5 meters. From it was cut off a piece of a length of about 2 meters (even 2, 5 meters left on the mast itself). In place of the antenna poking through hole, as narrow as possible and deep. In the pit falls and a piece of pipe with a sledge hammer being pushed as far as possible deeper into the ground. At the same time the ground should remain around 50 centimeters protruding pipe. Pit filled with concrete, which allowed a few days to get to grips.
From pipes with diameters smaller cut a piece of approximately 60-70 and is welded to the pipe sticking out so that it would be of a piece of pipe sticking out of 30-40 centimeters. Why is it necessary? The fact that the effective television antennas have very narrow beam pattern - just a few degrees. Therefore, initially orient them strictly to transmit the TV tower is simply impossible. And you must be able to rotate a television mast in the horizontal plane, that would point the antenna to the TV tower, or strictly repeater. In addition, if there is some telecenters, it makes it possible to deploy the antenna in one direction or another.
Collect the antenna itself in two ways. The first - an antenna sealed in a horizontal position. Thus a thin tube is inserted into 30 cm thick and more boil perimeter thicker end of the tube. When the antenna mast is ready for its top firmly establish itself with a TV antenna cable connected the required length. Free cable is attached to the mast with clamps. The cable should not be stretched. Be sure to leave enough slack - temperature compensation in the winter. Otherwise, in the winter it can burst. Mast high and miss the cable inside the pipe is not recommended. Fasten it inside the tube, you can hardly (except advance to pair it with a cable). The cable is quite heavy and if it is put up, sooner or later, he still will break under its own weight. In addition, the outlet - once the hub tension. If the pipe is ever and fractures, then rest assured - in this place. Therefore, I recommend not to take risks and to put the cable on the outside, every 50 cm to firmly secure its special plastic clips. They cost a penny, not broken, do not crack and are forever.
At the desired height to the mast attach a thin metal wire. And lowering the antenna (feeder) is attached to this cable. What would the cable did not feel the load on a break from its own weight.
The hardest part - is the rise and the installation of the mast. Actually she is not heavy, about 60 kilograms (I lifted it free). But in view of the fact that it is very long and the center of gravity is located roughly at the 4th meters high, one to pick it up it is not possible. The mast was raised as follows. Long rope was tied in place by 2 meters above the center of gravity. The rope is transferred through the horse home, who played the role of the unit. Then the antenna quickly led to a vertical position and planted on the rotator.
A second method eliminates the mast assembly procedure itself elevate antenna, and provides its assembly in place. But it needs to be able to work at a height of 3-4 m. It carries out welding work. With this method, all the pipes first cut to size and then inserted into one another, form a kind of telescopic antenna. Then attach to the top of the mast antenna push most subtle link and welded it to the second. As the extension cable is attached to the mast. And so long as the mast is not fully assembled.
After connecting the antenna and its settings (orientation), I was pleasantly surprised by the results. In the area of the Intercession (Vladimir region, about 100 km from the Ostankino TV tower) is not accepted all the 15 channels broadcasting. The height from ground level get a little more than 13 m. In addition, I am on the mast fixed 2 meter \ "pin \" for CB radios (civilian range of 28 MHz). The mast with an antenna showed excellent aerodynamics. The next day, after the installation was a strong wind, approx. 15 m / sec. Mast hardly swayed.
Yes, actually mast cheaper cost 1000 rubles. And all the pipes (except for the colon) - galvanized.