| PFS - Prepaired for Satellite receiving |
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THE PFS - technique People want be choose free. Also if it concerns the reception of television - and radio programmes. For this reason it is important that houses and buildings. Ready is for satellite reception (PFS). At the installation of PFS - system in a modernisation building, the adaptation of the existing coax cable system is generally sufficient. Pay attention, however, adapt of existing distribution systems is only possible when the pipes are large enough to replace the coax cable and if necessary new cables to lay. At new to build costs it ' take along ' of PFS at the construction of cable pipes moreover much more than the material costs. This text gives you insight in the most important technical aspects of PFS-installations.  THE PFS - concept: only one dish for several termination points for satellite recipient and/or pc. if required is possible it cable - or earthly indicator is incorporated. The LNB To receive full frequentstring of the ASTRA Satelitesystem(10,70 - 12,75 GHz) in a PSR-network, you need an Univesale Quatro LNB.This LNB has 4 outputs, that gives at the same time both polarisations and frequenty-strings through. The Quatro LNB gives the satelitesignals through by using a multiswitch, connected by a fourcable backbone. The dish To get better availability of the satellite signals and by compensation of disturbance of multi switch boosters Astra recommends to use a bigger dish than normal to receive DTH.  The multiswitch You can get differend kind of multiswitches. - Four or eight satellite-inputs; - The possibility to dividing earthly television (for example regional or local TV) or of cable television by the four (or eight) cables; - An extra (fifth or ninth) entrance and termination for partitioning of earthly television or cable television; - With or without feeding part; - With or without strengthening (actively or passively); - So-called stand-alone multi switches or multi switches arranged for cascade ring; - Several numbers of terminations: four, six or eight. Some multi switch systems exist from a basis Unit with an amplifier, where the strength of the incoming signals can be brought to one good level. The large choice to multi switches in several implementations makes it possible with these divides technique four up to four hundred connections to look after. A careful planning and calculation of larger divide systems are of course obvious. Advantages of multi switch distribution system The current and future available programmes and services of satellite systems can be passed on by 4 kabelig multi switch distribution system. By to use of 14/18V and 22kHz the switching criteria, the consumer can molars from both polarisations and links from total of 4800 MHz a link amplitude. Also the possibility exists cable reception and earthly reception in the system of incorporating. _ for this serve multi switch use with a extra entrance. Design of network There are two basis designs for distribution systems: Backbone and Star. Backbone - network. Backbone - network exists from a number of cascaded multi switches, mutually linked by four cabled backbone. In a building the four cabled backbone goes vertically down from the attic or the roof divided on each floor by a multi switches. At row houses the backbone run horizontally with multi switch in each house or in each second house.  Star network At an Star network cables of the multi switch (or a number of cascaded multi switches) run to the different households. The multi switch head station is generally placed on a call centre place, such as an attic or under a staircase, preferably in a closed cupboard. At the design of the system a new aspect must be taken into account: the availability of return path for interactive services such as pay-per-view and Internet by means of the satellite. At this moment the current tel. line serves as return path. A tel. connection therefore dense in the buurt of satellite connection must sit.  To add and passing on other satellite indicators Programmes of other satellites can be added easily to the wide bouquet of satellite systems through the use of IF - conversion. With IF - converter can be made a choice from some transponder frequencies on the other satellites, which are this way, to become converted so they lie next to each other and thus a block-system form. After it has been freed in the low link (horizontal polarisation) a part by means of a link filter, in this the new frequency block-system can ' be coupled ' with the still present indicators. Then these indicators are coupled to the correct entrance of the multi switch. The choice of the frequency range, which is freed by means of a link filter, must carefully, happen so that no important programmes lost go. At the planning of IF - conversion must be taken into account the fact, which the converted analogous frequencies must be again programmed in the recipient. Multi switch - distribution with 8 cables At small multi switch - distribution system with a limited number of households, becomes IF - conversion a precious matter. 8 Cables solution are then an alternative, where multi switch with 8 entrances must be used. The first 8 entrances (for satellite A) of the multi switch is used for 2 polarisations and links for the ASTRA satellite system. The remaining 4 entrances can be used for the transmission to other satellites - with maximum of four links or polarisations. Before 8 cables multi switch system are planned, must be checked if the recipients satisfy that to the required switch - criteria to select the indicators of the multi switch - entrances and the recipients can be programmed also as such. 1 CABLE DISTRIBUTIESYSTEM AND IF - CONVERSIONS At some houses where even if a cable lies, not possible of backbone or ASTRE network is use. Generally the cable has been moored according to a tree structure, which of house to house ' looped '. As temporary solution, until the house is renovated, these are able be used for the transmission of a number of transponder frequencies and if wanted of other satellites. The total capacity of an one cable system is only 1200 MHz. The system can pass on then maximum 25 transponders and not to be extended. Before such a conversion system is installed, must be checked if the digital recipient can handle the changed transponder frequencies. 
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