Which of the following RF connector types is most suitable for frequencies above 400 MHz?

Type N connectors are designed specifically to maintain a constant electrical impedance (usually 50 ohms) throughout the physical connection. This careful design minimizes signal loss and reflections, making them highly suitable and efficient for use at UHF frequencies and into the microwave range (over 400 MHz). In contrast, standard "UHF connectors" (like the PL-259) are ironically not well-suited for modern UHF frequencies because they do not maintain a constant impedance, leading to higher losses above 300 MHz. DB-25 is a multi-pin computer data connector, and RS-213 is a distractor likely confusing RG-213 coax cable with the RS-232 serial standard.