Datasheet

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Coaxial cables, abbreviation: Coaxial cables are double poled cables with a concentric
construction. They consist of an interior conductor (also known as the core), where a
tted exterior conductor network surrounds interior conductor at a constant distance. The
surrounding space consists of an insulator or dielectric material.
Flexible coaxial cables have cable screens and an interior conductor consisting of thin,
woven or braided copper wires. The screening can be supplemented with a foil – the
woven material can then have a lower amount of coverage. Coaxial cables for higher
capacities or higher screening factors usually consist of an interior conductor with a solid
wire and an exterior copper conductor (cable screening) with a high degree of coverage.
The interior conductor of coaxial cables used in the audio/video area has different diame-
ters (0.43mm to 1.13mm, for example).
Shorter cables are usually used in the area of television and video systems, longer ca-
bles are used for connecting radio and television networks. Antennae, transmitters and
receivers are connected to each other via coaxial cables in high frequency technology.
The line ow resistance (cable impedance) is the most important parameter of a coaxial
cable – it is stated independently from the length of the line and is stated in Ohms. Usual
line ow resistances are 50 ohms (general high frequency technology) or 75 ohms (te-
levision/SAT technology). The connection of cables to each other and also connection to
devices is done by using coaxial plugs which are determined, amongst other items, by the
construction and exterior cable diameter and the working frequency range.
The following connectors are often used:
· Belling-Lee plugs also designated as IEC 9.5mm plugs
(range of use: Cable television, terrestrial plug in antennae
connection, for example)
· F plug connectors also known as F plugs (range of use:
satellite televisions, for example); the interior conductor is
used as a male plug for these devices.
Belling-Lee-Plug (left), F-Plugconnector (right)
Many different coaxial plug connectors for various uses have prevailed in addition to
these coaxial plug connectors, such as BNC-, TNC, SMA-, SMB-, SMC-, UHF plug con-
nectors, MCX plugs, etc. for example. These are also used in the eld of television and
SAT technology.
Coaxial cables
A Patch cable (engl. to patch – to wire together), also shunt cable or twisted pair cable is
a cable type in network technology and telecommunications. Twisted pair cables contain
pairs of strands consisting of twisted pairs) of single strands. Patch cables are ready
made. The term does not refer to any specic cable standard but to variable, cable con-
nections which are not permanently laid. This is why the strands in the cable consist of
pliable copper strands. Contrary to permanently installed cables which consist of wires.
These can be reconnected according to requirement without a major effort. The cable
length is usually approx. 0.3 to 25 m permanently installed connections are usually used
for longer lengths. Patch cables can either be wired 1:1 which is also known as straight
through or crossed, where they are known as crossover cables.
Four paired cables area used as a matter of preference in current network installation.
The ISO/IEC-11801 (2002)E, a new description scheme in the form of XX/YZZ has been
introduced, since the old descriptions were not uniform and often lead to confusion or
were even contradictory.
SF/UTP (Screened Foiled Twisted Pair) (left), S/FTP (PIMF) (right)
Patch cable
copper conductor
strands insulation
pair
entire shield
cable jacket
copper conductor
strands insulation
pair
entire shield
cable jacket
pair shield
We therefore have the following:
XX for complete screening:
U = unscreened
F = foil screened
S = braided screen
SF = braid and foil screen
Y stands for paired strand screening:
U = unscreened
F = foil screened
S = braided screening
ZZ always stands for
TP = twisted pair
U/UTP (Unshielded Twisted Pair) (left), F/UTP (Foiled Twisted Pair) (right)
Categories complying with one respective requirement prole have been introduced
for easier classication of the individual cables. Categories 1 and 2 are only informally
dened; categories 3 and 4 are no longer commercially relevant (but can still be found in
old installations). Here are the most important categories for network installation:
Kategorie 5: CAT 5 cables are the mainly relevant installed basis for working
frequencies up to 100 MHz. Cables of category 5 are often used in structured cabling of
computer networks, such as Fast or Gigabit Ethernet for example.
Kategorie 6: CAT 6 cable is dened by EN50288. CAT 6 cables are used for working
frequencies up to 250 MHz. The rate of transmission deteriorates in longer lengths,
smaller overlaps do not present any problems, depending on extraneous factors. Fields of
application for CAT 6 are speech and data transmission and also multimedia.
Kategorie 7: CAT 6 cables are used for working frequencies up to 600 MHz. A Cat 7
cable satises the IEEE 802.3an standard as is therefore suitable for 10 Gigabit Ethernet.
copper conductor
strands insulation
pair
pair shield
cable jacket
copper conductor
strands insulation
pair
cable jacket