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for building developers,
and all who want to do properly
antenna systems for TV, SAT TV, WLAN, GSM, DCS, 3G.
SignalNET - how to wire the house - signal/multimedia installations
Building houses, every builder begins with the foundations. The interior finish has to be started with cabling. When designing electrical system, it is indispensable at the same time to take into consideration signal cabling: telephone, computer, RF (terrestrial and satellite TV, FM), door entry system etc. Nowadays many developers choose flexible systems like SignalNET - the final set of the equipment can be configured by the owner - to satisfy their individual needs (it is also connected with the money they want to spend).
Not long ago the offer of television was limited to transmission of two programs. A single antenna mounted on a balcony and connected directly to the TV set made the whole installation. Since then, the number of programs has considerably increased, and new satellite and cable technologies have been introduced. The real change in this domain is coming now, with digital technology. Television installations enable access to the Internet, phone conversations, CCTV monitoring and control of alarm systems, remote reading of meters (electricity, gas, water) and Internet shopping. Due to revolution in wireless technology (cellular networks, Wi-Fi), many buildings have to be equipped with suitable systems (antennas, repeaters, access points) supporting these services.
Development of television and telecommunications promotes quick spreading of modern antenna systems - just like in the case of common use of electric devices, which resulted in standards of designing electrical installations. Usually the law concerning construction of buildings indicates necessity of designing and implementing antenna installations only in the case of multi-family buildings. However, lack of such an installation in a one-family house considerably limits access to the latest achievements of television technology. We provide some advice for all who would like to do such installations.
First of all one should have the possibility of using terrestrial television as well as cable or satellite broadcasts. The whole installation should be designed in the way that the further modernization and replacement of elements will not require demolition of the building structure (however, a comprehensive modernization may be necessary when introducing new technology e.g. optical fibers). Internal installation should provide every room with an outlet enabling reception or distribution (from an RF modulator, RC extender etc.) of RF signals. The concept of any antenna installation may be derived from the procedure presented below:
1. Basic guidelines.
1.1 The place and way of mounting antennas
Most of failures of antenna installations are the result of a collapse of improperly fixed mast or a break of badly laid cables. Nowadays, the most popular solution is clamping the antenna mast to a chimney. Masts can also be fixed with wall brackets. Satellite dishes, normally directed southwards, are usually fastened on separate masts. Antenna cables should enter the building already on the roof.

A WLAN antenna has to be mounted the way that guarantees mutual visibility with the counterpart (usually of the Internet service provider).
An external antenna cooperating with a GSM/DCS/3G amplifier/repeater improving signal coverage inside the building has to be situated in the place where the signal level from the selected operator is optimal, and the isolation between the antenna and the internal antenna/s is sufficient for stable operation of the system.

1.2 Kind of installation (pass-through, star-shaped, mixed)
Currently the pass-through installations are not preferred, especially in larger systems. Star installations are more universal and more resistant to interferences caused by the connected receivers. They are used both for distributing terrestrial and satellite programs (e.g. multiswitch installations).
Even if at the time of construction the investor is not planning to install multiswitch system, it is worth to provide a complete wiring, in order to avoid any construction work in the future.
1.3 Method of laying cables
Cable trays become more and more popular solution for placing electrical, computer, telecommunications and RF installations in new office blocks. The core is the main vertical conduit from the basement to the attic, with possibility of leading branches on every floor. Such layout will allow to implement new installations, to change location of main devices etc.
It is not recommended to lay unprotected cables just under the plaster. Each cable has limited life and can also be accidentally damaged (e.g. when drilling holes in the wall). The exchange would be extremely difficult.
If the installation is to be laid traditionally, conduit tubes should be applied.
1.4 Location of splitters, tap-offs and amplifiers (with regard to possibilities of power supply)
The basic rule is that amplifiers should be located as near antennas as possible. This recommendation is best realized by using mast amplifiers - however they are exposed to the disintegrating action of weather conditions. So the best places for installation of indoor amplifiers, including the maintenance, are attics.
Multiswitches, repeaters, or wireless LAN access points must be installed in dry areas, away from heat sources, usually in the center of the building.
Splitters should be mounted in easy accessible places without a risk of vapor condensation (highly corrosive agent).
1.5 Layout of antenna outlets
Antenna outlets are manufactured in flush or surface versions. Especially in the case of flush equipment it is essential to plan out the positions in a rational way.
2. Selection of elements of an installation with regard to signal quality,
number of received programs and the risk of interference.
2.1 TV, SAT TV, WLAN, GSM, DCS, UMTS antennas
For receiving terrestrial broadcasts there are used antennas working in the following bands: FM (radio), VHF (mostly only for one TV program; not used in some countries e.g. Great Britain), and UHF. In the case of FM antennas it is well to pay attention to receiving signals in both polarizations, horizontal and vertical. Among TV antennas, the YAGI-UDA usually provide the best results.
The "azimuth-elevation" dish mount enables reception from one satellite position only. But mounting two converters on a double mount, it is possible to receive programs from two close satellite positions. Reception of broadcasts from several satellites is possible by use of "polarmount" type of mounting and positioner. The recommended sizes of dishes depend on geographical location of the building and the satellites that should be received.
Wireless installation is currently the popular way of Internet access. The users employ wireless adapters in their computers, or external access points. It is indispensable to get information on the band used by the ISP, location of the transmitter, signal level etc. - in order to use or buy proper equipment and antenna (if not supplied by the ISP).
GSM/DCS/UMTS amplifiers/repeaters require a special type of antennas. They should be carefully chosen. It is very important not to use an antenna with too large gain which would dramatically increase the probability of overdriving the repeater or even parasitic oscillation, causing the device to be inoperative. One should observe the rule that higher gain of the external antenna requires greater separation between the antenna and the interior antenna/s.
We suggest reading the article >>> Selection of Terrestrial TV Antennas
We suggest reading the article >>> Self-help book for WLAN installers/providers
We suggest reading the article >>> How to improve GSM wireless signal?
2.2 Cables
Multiswitch systems require to lay 4 or 8 coaxial cables (for one or two satellites) and at least one cable for terrestrial signals. Each outlet is connected to one or - in the case of using PVR receivers - to two outputs of the multiswitch.
Coaxial cables of 75 ohm impedance are widely applied is TV/SAT installations. For reception of satellite programs there have to be used coaxial cables characterized by low loss in 950-2150 MHz band. These days buildings are being equipped with uniform cabling, so the choice is one - satellite cable. We recommend cables from the TRISET-113 series. For outdoor applications one should use PE versions.
Article on modern cabling: >>> Wiring in single-family homes
For connecting access point with the antenna there should be used coax working up to 6 GHz, e.g. Tri-Lan 240. The cable has much better parameters in 2.4 GHz band, but first of all - it will allow to migrate the system to 5 GHz band in the future.
We recommend the article >>> Use of coaxial cables in WLAN systems
CAT 5e UTP Cable: NETSET BOX [305m]<br /> (for indoor applications)
CAT 5 UTP Cable: NETSET BOX UTPw 5e <br />(outdoor - gel-filled, black) [305m]
The primary cable used for wiring LAN (Ethernet) is a cat 5e twisted-pair cable (UTP/FTP). In the case of residential buildings, the typical cables are indoor UTP cable in PVC sheath (indoor installations) and outdoor UTP cable in PE sheath (outdoor installations).
It is important to use cables of the highest quality. The cost and effort associated with the replacement of cables is high. We therefore recommend best cables, tested by independent research institutes. The examples are NETSET cables tested by Central Testing Laboratory of the National Institute of Telecommunications in Warsaw, Poland.
2.3 Amplifiers, splitters, tap-offs
Antenna amplifiers are used in the cases when input signals are weak, or cable lines are long, or the number of sockets is large. For a small installation and good signals one can use broadband amplifiers with built-in input diplexers. In more difficult conditions the proper solution is to use channel amplifiers that amplify only the desired channels, which eliminates external interferences, as well as unwanted products generated by overdriven broadband devices.
Article on RF amplifiers: >>> AMPLIFIERS in antenna installations
Article on passive distribution devices: >>> Splitters and tap-offs
2.4 Antenna outlets
Typical antenna outlets have two paths, TV and FM. For reception of satellite programs one should use satellite outlets with ''SAT'' mark. Universal outlets ensure return channel (indispensable e.g. for Internet access).
2.5 GSM, DCS, 3G amplifiers/repeaters
Repeaters are used to amplify signals of GSM, DCS or 3G services and to distribute them inside buildings. Any repeater has to be connected to an external antenna directed toward the base station of the particular network, and internal antenna/s that distribute/s the amplified downlink signals and receive/s uplink signals from the terminals (phones or modems).
The basic information that one should know before purchasing a repeater is the kind of cellular service used and how much area is to be covered with the amplified signal.
When deploying indoor antenna/s, one should pay attention to the number of rooms that are to be covered by the amplified signals and the total area. Splitters allow to connect several interior antennas.
The whole range of items sold in our store has been divided into sections. When choosing a section, there is available additional information on the right of the page.

We especially recommend the article providing detailed and universal diagrams of antenna installations.
Properly designed antenna installation in the building can be also used for distributing video from the local CCTV system improving security of the residents.
DIPOL promotes modern cabling systems for buildings. More information in the article:
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