The F connector is a coaxial RF connector commonly used for “over the air” terrestrial television, cable television, and universally for satellite television and cable modems, usually with 75Ω RG-6/U cable or in older installation, with RG-59/U cable.
The frequency range is from DC to 1 GHz, extended range to 3 GHz with RF leakage of -100 dB min at 1 GHz.
Connectors mate using a 3⁄8 in-32 unified extra fine (UNEF) thread. The female connector has a socket for the center conductor and external threads. The male connector has a center pin, and a captive nut with internal threads.
The F connector is seen on Tektronix products like the 1705.