Reception of on-air broadcasting through traditional antennas is the most affordable way to broadcast a television signal. Even against the background of the transition to a digital transmission format, familiar devices do not lose their relevance. On the radio equipment market, you can find antennas for different purposes, taking into account the nuances of installation and operation. At the same time, it should be noted that Russian equipment manufacturers are widely represented in this segment, and this also affects the price reduction. Despite the arrival of more technological installations, a passive television antenna is still in demand, the advantages of which include reliability and ease of maintenance. Of course, there are obvious drawbacks to such devices, but in some cases it is quite possible to put up with them.
What is the feature of a passive antenna?
The main difference between passive models is that they do not require connection to the mains. For the user, this means that there is no possibility of connecting an amplifying adapter. Accordingly, in the design of such installations there are no transistors, microcircuits or other electronic components with electronic filling. Therefore, the statementthe question of whether an active or passive antenna will better cope with the tasks in a particular case? It is important to understand that the presence of active elements in the design makes it possible to receive a signal in the most difficult conditions precisely due to additional amplification.
But there is a downside to this decision. The fact is that the absence of electronics saves passive models from characteristic interference and noise, which also improves the quality of reception. In addition, one cannot speak of the complete absence of amplifying ability in equipment devoid of special adapters. The geometry of the design, which passive antennas have, is initially oriented towards independent and high-quality signal reception. Another thing is that these abilities are not always enough to service the equipment in a remote area from the relay station.
Main characteristics of passive antennas
From the point of view of the consumer, the main characteristic is the gain, measured in decibels. As already noted, passive models lose in this indicator to active counterparts, however, the elimination of interference compensates for this flaw. Usually passive antennas (TV) provide gain in the range of 12-20 dB. This is sufficient if reception is supposed to be in the coverage area of the tower that distributes the signal. There are also models with a coefficient of more than 30 dB, but you should be more careful with such devices, since this level is more likely to be characteristic of active devices. By the way, an important characteristic of passive installationsis the number of functional parts in the design. It is on them that the antenna's own ability to enhance reception without electronic means depends.
Indoor antennas
Indoor models are designed from the ground up for a stable and strong TV signal. It must be understood that even active devices do not always cope with providing a high-quality display in a room, so the choice of passive antennas for indoor use should be approached more carefully. But if the repeater is in an accessible coverage area, then this option will be beneficial for several reasons. Firstly, a passive indoor antenna eliminates the need for roof mounting with a long cable connection. Secondly, such models can be adjusted in direct accessibility through special "antennae". But, again, providing a high-quality "picture" is possible only if there is an appropriate signal from the broadcasting tower.
Car models
Devices for cars in general operate on the same principle as conventional television receivers. In particular, a passive car antenna also works with radio waves of the electromagnetic field, but then sends it to the radio. In traffic conditions, signal stability is especially important, so active models are in high demand. But passive designs also have their advantages, for example, they are distinguished not only by ease of use and compact size, but also by high sensitivity.
There are some nuances of operation of such devices. It is important to consider that a passive car antenna is essentially external, so it must be protected from mechanical stress. This primarily applies to telescopic retractable structures.
External antennas
In terms of reception quality, this is the best option. In the case of outdoor models, you do not need to think about third-party interference, since the design is calculated for long-range reception. However, obvious interference near the installation site should still be eliminated. As a rule, an outdoor passive antenna has massive dimensions and many functional elements in the design. It is these qualities that allow such receivers to work at long distances from repeaters. But you will have to pay for these advantages with the need for installation on the roof. The antenna must be securely fixed so that wind and precipitation cannot interfere with its operation. In addition, a cable connection is required. If we are talking about a private house or a summer house, then there will be no special problems with this, but in multi-storey buildings one cannot do without multi-meter coaxial wires.
Producers and prices
Classic models of passive antennas are produced by companies such as Locus, Deltoplan, Anteks, etc. Most often these are inexpensive devices costing 300-500 rubles. Room models can be purchased for 200–250 rubles. Street versions are a little more expensive, but even a demanding buyer can easily meet 1000 rubles. Automotive passiveantennas are produced under the brands "Triad", "Mystery", "Prolodgy", etc. In this case, the cost may increase, as manufacturers complete the models with additional accessories. On average, the prices for such antennas are 1000–1500 rubles.
Positive feedback about passive antennas
Among the main advantages that users of passive antennas note are easy installation, no need to connect electronic components and high reliability. A simple design in optimal operating conditions is able to provide good reception and a “picture” without unnecessary interference, which active models sin with. Also, many note that passive antennas perform better in adverse weather conditions than alternatives. Reinforced design without unnecessary electronics is stable reception and protected from external influences.
Negative reviews
As practice shows, all the advantages of passive equipment are reduced to zero if the repeater does not provide the proper signal level. Users note the dependence of such devices on the quality of the local TV tower. Particularly problematic in this regard are passive antennas intended for installation in a room. The very concept of such installations assumes small dimensions, therefore, the function of the reinforcing structure is also minimized. For this reason, for indoor use, experts still recommend turning to active models, the operation of which is supported by the power supply.
Conclusion
The passive antenna has an elementary design, so many home craftsmen replace it with improvised materials in the form of metal parts. In some cases, good results are also achieved when simulating active devices. However, even with the competent implementation of the structural part, it is far from possible to count on obtaining the expected result in all cases. The fact is that a passive television antenna, with all its simplicity of design, has one essential characteristic. This is the matching of the impedance indicators with the cable, due to which the reception parameters are optimized. In addition, the owner of the factory antenna can count on the convenient and correct implementation of the design settings. As a result, a balanced adjustment of the functional parts allows you to count not only on high-quality TV signal reception, but also on work with the radio range. It is almost impossible to achieve a similar quality with the help of improvised devices.
