Installation Guide

  
  
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Halogens

   
WHAT IS DIGITAL TRANSMISSION?

Until recently, radio and television signals have used analogue technology. Through these analogue transmission systems, signals can change continuously.
Today, digital transmission technology has been developed for both satellite TV broadcasting and cable network TV distribution. Unlike analogue signals, digital technology allows the continuous transformation of analogue signals in a discreet sequence of alternating pulses.
The use of a digital transmission system allows the following advantages:

  • High Definition television pictures;
  • Increase of available channels and services;
  • Possible scrambling of the transmitted signals;
  • Interactivity;

Broadcasting or receiving digital transmissions demands that all active and passive components be reliable and that they demonstrate uniform performance of the technical parameters.

They have been particularly optimized in the CAVEL DG series of coaxials as follows:

  • SRL:

    • the values of the Structural Return Loss are optimized thanks to a dielectric manufactured by gas injected PE; the reflection co-efficient values are within 3-4% of the full frequency range from 10 to 2400 MHz so that accordingly we have an SRL of about 30 dB;

  • Attenuation

    • very low, just equivalent or even slightly better than typical cables with only 75 dB Screening Effectiveness

  • Screening Effectiveness

    • this is the parameter used to define the outer conductor (screen) capability to oppose external electromagnetic interferences. The amount of attenuation occurring to the interfering signals are over 90 dB through the full frequency range from 30 to 1000 MHz. It is very important that the electromagnetic signals carried by the coaxial cable must not be disguised by interfering signals because the latter could deprive the receiver of the right digital signal make up.

The above given characteristics take into consideration that the DG series of coaxials can be considered drop cables of the highest calibre and the most suitable for any TV reception application be it terrestrial, satellite and cable, analogical or digital.

    

 
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Digital transmissions
Petrol Jelly


ABOUT HALOGENS (ZH)

The CAVEL coaxial cables included in this series, identified by the suffix ZH (Zero Halogen), have been provided with a RAL7001 grey sheath, classified as M1 by the CEI 20-11 specs., made safe by a thermoplastic compound in case of fire.
It is well known that ducts crowded with cables can lead to the rapid propagation of fire, and that the worst danger for health and risk to life occurs by inhaling toxic gases generated by thermoplastic materials during their combustion.

Gases generated by the combustion of clorine based compounds, such as PVC, have:

  • a high corrosion power, which is able to damage any common electronic device;
  • a high toxicity level, such that 500 ppm of hydrochloric acid can be fatal after an exposure of 30 minutes, as opposed to 100,000 ppm of carbonic anhidride or 4,000 ppm of carbon monoxide.

With the aim of suppling our customers with a number of security cables able to cover many possible applications, we offer the present range of ZH coaxials, provided with a sheath having the following characteristics:

Flame & Fire Retardant
for a single cable vertically installed in accordance with IEC 332-1 Specs;
for a bundle of cables vertically installed in accordance with IEC 332-3 Cat C Specs;

Low Smoke & Fume Emission
lower than 1,5 in accordance with CEI 20-38 Specs;
values measured in accordance with IEC 754-1 Specs;

Zero Halogen
halogenidric gas emission lower than 0,3% in accordance with CEI 20-11 Specs;
toxicity index lower than 2 in accordance with CEI 20-38 Specs;
values measured in accordance with IEC 754-1 Specs;

UV Resistant
in accordance with ASTM D2565 Specs.

The LSZH (low smoke zero halogen) sheath on our coaxial cables has recently passed the homologation approval of the ISPT (Italian Senior Institue of Post and Telegraph). As a result the compound has been prescribed by Telecom Italia for the drop coaxial cables for the so called ‘Socrates project’.

We recommend the use of this range of cables for any installation in a pubblic building and in any environment where there is a likely presence of many people: e.g. hospitals, schools, hotels, banks, tube stations, cinemas, theatres, airports, etc.

Beside the peculiar security characteristics of the outer sheath, the ZH cables match with all the other physical and electrical characteristics of the equivalent SAT series and DG113 cable. Therefore they can be used to cover most applications of the terrestrial and satellite downlead installations.

The pictures show the different opacity of the smoke generated within 6 minutes of combustion against a bundle of cables with a common PVC sheath and those with an LSZH sheath

    

  
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Halogens
Multipair coaxials


COAXIAL CABLES FOR CATV SYSTEMS

This range of coaxial cables provide:

  • low losses;
  • high screening effectiveness;
  • long lasting stability of attenuation due to the physical gas injected foam dielectric technology.

These cables are suitable for laying the branch stretches of long TV distribution systems, again for both terrestrial and satellite reception, which are systems very close in complexity and as extensions to actual cable television networks.

Only cables provided with petrol-jelly flooding compound filling (PJ) interposed between the braid and the PE sheath should be used for underground installation. We suggest they are installed in any environment where the presence of water and/or a high ratio of moisture are likely. For instance, tunnels, underground car parks and so on.

Cable type 27/115FC gives the lowest attenuation values and must be considered the most suitable for the installation of long runs.

Cable type RG11FC is provided with a copper clad steel inner conductor wire (CCS) to increase the cable’s strength particularly in the case of difficult installations.

Cable type CATV11AP has been provided with a stranded rope messenger for the installation of catenary stretches on TV distribution systems.
 
 

  
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Petrol Jelly


MULTIPAIR COAXIALS FOR SMATV RECEPTION AND 1st IF DISTRIBUTION

Today, both single and comunity satellite reception systems are often provided with a dual-feed parabolic antenna i.e. where the satellite dish is provided with two LNBs suitable for receiving signals from two different satellites or groups of them. In this case the drop line requires two coaxial cables, one for each LNB.

Besides, nowadays the multiswitch distribution system makes it possible to distribute independently, among all users of the same building, a wide range of both satellite and terrestrial television signals. For this reason, the need for the so called "light cabling system" is carried out by the use of multipair coaxials.

Due to this technology, the signals distribution requires:

  • four coaxials for the satellite distribution and 1 coaxial for the terrestrial distribution, where the dish is provided with one converter.
  • two groups of 4 coaxials for the satellite distribution and 1 coaxial for the terrestrial distribution, where the dish is provided with two converters.

With the aim of offering the easiest solutions to the professional installer we designed the multipairs shown here.

The use of such cables allows the installer to save a lot of time when laying the distribution network.