We have been assembling coaxial cables since the early days of Ethernet in the 1980s. With the introduction of Thin Ethernet, the 50 Ohm coaxial cables were equipped with BNC connectors whereby branches could be made with T connectors. For that application, coaxial cables are generally no longer used, but we still assemble coaxial cables with different thicknesses, impedances and outer sheaths for countless other applications.
Call me back
Wondering if we can do something for you? Leave your details here and we will call you back as soon as possible. Of course, you could also fill in the contact form.
Construction of coaxial cable
A coaxial cable consists of two concentric conductors: the inner copper conductor (core) surrounded by the braided shield. This is the enclosing outer conductor that is connected to earth. The better coaxial cables also have a metal foil around the braided sleeve for even better shielding of high frequencies. These conductors are separated by an insulator: the dielectric. The beauty of a coaxial cable is that little or no interfering signals can leak in or out. This is because the axes of both conductors coincide, so that the electric and magnetic fields of the inner and outer conductors cancel each other out. Therefore coaxial cables are used for high-frequency signals, such as in video equipment, in RCA cables between sound equipment, or - as in the past - in a computer network.
Characteristic impedance of coaxial cables
A coaxial cable, like any other electrical cable, has a certain characteristic impedance. This is important at high frequencies. Depending on the application, we mainly know the characteristic impedance of 50 Ohm and 75 Ohm. Here 50 Ohm is especially used for computer networks and radio communication equipment, and 75 Ohm for radio, television and video equipment.
Reflection of the signal
An impedance transition, such as the transition from the cable to the device, causes reflections of the signal. This disturbs the original signal. To prevent reflection of the signal, a device to which a coaxial cable is connected, must have an input impedance equal to the characteristic impedance of the cable. Reflections can however also occur when a connector on the coaxial cable is not mounted properly. For this reason, our coaxial cables are tested by us, because we only supply high-quality coaxial cables.
Attenuation and losses
The attenuation of a signal per unit length (usually 100m) is expressed in decibels (dB). The attenuation depends on the height of the frequency. At higher frequencies, the attenuation in the cable will also be higher.
In a coaxial cable there are also two loss effects: dielectric losses and the skin effect. In the case of the skin effect, very high frequency signals run only in the outer layer of the conductor while lower frequency signals use the entire cross section. Dielectric losses occur because the dielectric dissipates energy at higher frequencies. This loss depends on the material of the dielectric used.
Signal losses also depend on the insulation material of the outer jacket and the diameter of the coaxial cable. The thinner the cable, the greater the signal loss for a given length.
When designing coaxial cables, it is therefore important to take all these effects into account. So if you need any help with this or if you are looking for a reliable partner for the assembly of high-quality coaxial cables, you can always contact us without obligation.
