1. Characteristic impedance
The characteristic impedance of BNC radio frequency connectors is 50Ω and 75Ω. Many series of connectors have both 50Ω and 75Ω specifications. Generally speaking, 50Ω connectors are mostly used for high-frequency and high-performance products; 75Ω connectors are mostly used for products with lower frequencies, and the frequency is mostly below 4GHz, especially for consumer electronic video. Users should choose a connector that matches their impedance according to their own products. If the user uses a 75Ω RG 59 Cable, he should choose a 75Ω connector.
Each type of radio frequency connector has a frequency range, and the user should understand the working frequency of his product to choose the connector. Choosing a connector lower than the required operating frequency will affect the electrical performance of the whole machine; or choosing expensive, high-precision and high-frequency connectors will cause waste. It should be noted that the frequency of use of connectors designed by different companies is quite different, and the frequency of use of inferior products is far from reaching the industry standard. When selecting the connector, the user should confirm the electrical performance description of the product.