Why don't VHF or UHF antennas use waveguides as feed lines?

VHF (Very High Frequency) and UHF (Ultra High Frequency) antennas don't use waveguides as feed lines primarily due to the practicality involved with waveguide dimensions at these frequencies.

At VHF and UHF wavelengths, the physical size of waveguides becomes quite large, making them unwieldy for general use in applications such as television broadcasting, two-way radio communication, and other wireless transmissions. Instead, coaxial cables or other types of transmission lines are more convenient because they allow for much easier handling, installation, and maintenance.

Additionally, the larger dimensions of waveguides result in more significant losses and difficulties in managing the physical infrastructure, especially in environments where space and portability are considerations. Consequently, for VHF and UHF frequencies, other transmission lines offer a more manageable solution without compromising performance significantly, making them the preferred choice.