Full-Wave Loop Antenna.
If you're having trouble viewing this video, please insert this URL into your browser search box: https://youtube.com/watch?v=HpoOPdelP8Q. Stan Gibilisco (W1GV) outlines some of the theoretical and practical considerations for designing, building, and using full-wave loop antennas for both HF and VHF amateur radio bands. You can get multiband use out of a full-wave loop by using balanced feeders into a balanced antenna transmatch (i.e. "tuner").
Aloha es 73 de Russ (KH6JRM).