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It needs take into account of not only performance requests but also economic factors in connector selection. Performance must meet the needs of system wiring and economy must fulfil axiology. When selecting a RF coaxial connector,you need think over of following four aspects:

Connector interface (SMA SMB BNC etc.)

Electric performance installation and cables

Portconnect form (PC board cables panel etc.)

Mechanical structure & plating (militarycommericial)

1.Connector interface

Connector interface is often determined by its application. At one time, it need meet electric and mechanical performance.

With bayonet lock, BNC connector is often used in radio connection with frequency under 4GHz, network system, apparatus, instrument and Internet.

TNC's interface likes BNC's except the screw interface. It's still used in 11GHz,and as good as in oscillation.

SMA connector is used widely in fields such as aviation , radar, microwave communication, digital communication and so on. Its impedance is 50Ω, frequency of flexible cable is under 12.4GHz, and maximum frequency of semi-rigid cable is 26.5Ghz; type of 75Ω has widely applied foreground. The size of SMB is smaller than that of SMA. For its screw interface, it owns stronger mechanical performance and wider range of frequency. It is mainly used in military and can replace L9. Frequency of commercial type 50Ω is up to 4GHz and 75Ωis 2GHz.

SMC is similar to SMB. For its screw interface, it owns stronger mechanical performance and wider range of frequency. It mainly used in military or high oscillating environment.

Insulated material of type N screw interface connector is made from air. So it costs less. Its impedance is 50Ωor 75Ω, and frequency is up to 11GHz. This type is often used in area networkmedia spreading and apparatus testing.

MCX series connector provided by Jingcheng company are good at small size and connect reliable, which make it widely used in the telecommunication fields.

2.Electric performanceinstallation and cables


Impedance  of connector must match that of system and cable. It need notice that not all impedance of connector interface is 50Ωor 75Ω. If not match, it will make system performance decreased.

(2) voltage

Make sure that working voltage is under maximum tolerance voltage.

(3) maximum working frequency

All kinds of connector have a maximum working frequency. Some 75Ω products for commercial use have a minimum working frequency limit.

Every interface form has characterized except electric performance. For example: type BNC (bayonet lock) has facile installation and cheap price, widely used in low performance wiring; SMATNC series using screw coupling, meet the request for high oscillating environment; type SMB can join and cut rapidly, so become more and more popular.

(4) transmission cable