The BNC coaxial RF connector got its name from the names of creators, engineers Paul Neal and Karl Conselman. Full name - "Bayonet Neal - Conselman". The word bayonet is of French origin and means bayonet. The connector closes using the lock, which was on the guns for bayonets.
The BNC connector allows its use in circuits with voltage up to 500 V and frequency up to 3 GHz (wavelength 10 cm). In this case, two standardized wave impedances are used: 50 and 75 Ohms. If the BNC connector used with the corresponding cable, and their wave impedances coincide, then the losses at this connection do not exceed 0.3 dB.
Coaxial cable diameter usually limited to 8 mm. The material for the connectors is bronze with a silver or gold coating. The insulating ring is made of the material with the lowest dielectric losses: fluoroplastic or polystyrene.
Also BNC-connector for soldering must have fluoroplastic insulation. When soldering, the polystyrene will be melted, the central part will leave its axis, and the connector will become unusable.
In order to prevent cable breaks, SARMATT manufactures connectors, the ends of which are equipped with a safety spring. This guarantees a possible number of disconnections and connections in excess of 500.
The BNC connectors in question are used to connect devices operating at high frequency (oscilloscopes, generators, etc.), transmitting and receiving devices, satellite antennas, cable television networks, and video surveillance cameras. In addition, these connectors are used to organize local area networks using Ethernet, 10Base2 and even 100GBase technology. To do this, use the T-connector, "tee". The trunk is connected on a common axis, and the branch goes to the network node (workstation). The end connectors are equipped with termination plugs to suppress the reflected (standing) wave.
Usually, a socket (“mother”) is installed in the equipment, and a plug (“male”) on the cable. By design, the BNC connectors are straight and angled. The latter are used where the cable should make a sharp bend, which is extremely undesirable for coaxial cables. Therefore, this task is assigned to the angular structure.
The idea of a bayonet lock was very successful. The threaded connection is inconvenient to use, since you have to rotate the cable along the axis. Even the union nut does not always make the situation easier. Threaded connections tend to jam, turn badly and take too much time to connect and disconnect the connector. A friction-based connection, as in household appliances, is unacceptable because the connector is very easy to pull out of the socket.
A bayonet mount closes and opens very easily. It is enough to press on the connector and rotate it along the axis. All this takes no more than a second. At the same time, it will not be possible to pull out the connector.
Therefore, the BNC connector replaced almost all the connectors precisely among laboratory devices. It is also best suited for computer networks - because of the speed of working with it and the impossibility of accidental disconnection.
BNC marking includes the following options:
- BNC - soldering or crimping;
- BNC-T - tee (for Ethernet adapters);
- BNC-F - threaded connector option;
- BNC-I - connection of two cables.
For measuring instruments, exclusively soldered connectors and preferably with gold-plated contacts should be used. This reduces possible errors. For other cases, crimp connectors are suitable, but they need to be mounted only with a special crimp tool. The last version of the connectors is much cheaper than the instrument ones, it is mounted faster, therefore it is more optimal than soldering.
Thus, if you want to mount a local area network of "n" computers, then for this you will need to make a minimum of "2n" connections on the cables, and sometimes more.