The most widely used types of feed line are coaxial cable, twin-lead, ladder line, and at microwave frequencies, waveguide. Particularly with a transmitting antenna, the feed line is a critical component that must be adjusted to work correctly with the antenna and transmitter.

The most common type of feed line is coaxial cable, or simply coax. It is called coaxial because there are two circular conductors positioned “co-axially” (on the same axis), one inside the other.

Three types of feed lines are used by amateurs: Coax, Balanced Line, and Waveguide. Coaxial Cable is made of a central conductor surrounded by a layer of insulating material with a second layer of conducting material over that and insulation on the outside.

The use of a half wave, or multiple thereof, coax or parallel conductor feed line connected to the antenna will allow the antenna to be raised to its operating position for measuring impedance.

Mar 28, 2025 · Choosing the right feed line for your antennas is a critical decision to your station ... Table representing loss of Coax Cables in db per 100ft. An overview of coax cable often called coaxial feeder or RF cable used to feed ... Common mode currents can flow in all sorts of systems not just antenna feed lines ...

Apr 12, 2024 · The main types of antenna feed lines include coaxial cable, waveguide, microstrip line, twin lead, and balanced line, each with specific applications and characteristics. Coaxial cable is a type of transmission line that is used to carry …

Oct 16, 2024 · One of the most common types of feed line used is coaxial cable. Coaxial cable is favored because it offers a balance of ease of use, cost, and performance that suits the needs of most amateur radio operators.

Technical Recap: Coax feed line chokes all have unbalanced input and either balanced (BALUN) or unbalanced (UNUN) output. It is the output connection that determines whether a choke is a balun or unun. Feed line chokes are a special case of impedance transformer with an input/output impedance ratio of 1:1.

Coaxial cable feed of patch antenna. The position of the feed can be altered as before (in the same way as the inset feed, above) to control the input impedance.

Jan 25, 2023 · Patch antennas can be fed with a coaxial probe from the back side of the PCB. See how to design a patch antenna module PCB with a coaxial feed.