In RF connectors, there is a more popular product, namely the sma connector, so when the procurement staff in the procurement of sma connector, what are the key points to note? In general, in the procurement of sma RF connectors, it is necessary to take into account the interface mechanism type, electrical performance, mounting method, termination form, material and coating five aspects.
1, interface institutional type
The connector connection mechanism not only provides convenient and fast connection or separation of coaxial transmission lines, the key is to provide stable electrical performance and environmental protection devices, when the use of the occasion does not have enough space to rotate the connection nut, should choose a non-twisting connection mechanism. In addition, for frame connectors, non-twisted connection mechanisms are also very useful.
2, electrical performance
a. Feature impedance: the connector should match the impedance of the transmission system and cable, otherwise it will lead to a decrease in system performance; b. Voltage resistance: The maximum pressure resistance value of the connector should meet the pressure resistance requirements used in the system; In general, if you are in a broadband application, you have to sacrifice some favorable broadband impedance matching characteristics to obtain the required high-voltage rating. c. Maximum productivity.
3, cable loading method and cable type
a. Cable connection: There are two types of connector cable fitting methods: a welding center conductor, combing braided wire standard tightening method is still common, especially suitable for no special installation tools, and facilitate on-site maintenance. Two. Welding the center conductor, crimping the clamping method of the braiding layer. Due to the high efficiency of the crimp method. With reliable termination performance and good consistency, termination has become a common approach today. b. Cable type: The appropriate connector should be selected according to the characteristics of various types of cables used (e.g. soft cable, semi-rigid cable, wrinkled conductor insulated cable, foam insulated cable), and the general outer diameter of small cables and small connectors should be matched.
4, termination form
Connectors can be used for RF coaxial cables, printed circuit boards, frame drawer-type functional components and their interface.
5, materials and coating
The housing and internal conductors are mainly brass, palladium copper, tin bronze, insulation materials are mainly teflon. The center conductor is generally coated with silver or gold, and the shell is coated with nickel or silver. SMA, SMB, SSMB, SMC external conductors are all gold coated. RF coaxial connectors are used to transmit RF energy with frequency ranges of up to 18GHz or higher. The basic structure includes: positive and negative neutral contact parts, external interface material, the outermost contact part, the outer part plays the same function as the cable outer shield: both transmission signal, shielding ground.
Here, I hope that all sma connector buyers, can pay attention to the above five points, do not blindly purchase. Blind procurement will only make procurement work buried hidden dangers, a series of unimaginable problems.
