Flag semaphore towers

In the later medieval period, semaphore towers using flags and signaling devices emerged. These towers allowed for visual communication over distances, unable to be covered by voice or sight alone. Semaphore signals required prearranged codes understood by both sender and receiver, akin to Morse code in amateur radio. This system emphasized the importance of clear, coded communication and line-of-sight visibility, concepts central to amateur radio operations. Semaphore towers’ strategic placement for optimal visibility parallels the positioning of antennas and repeaters in amateur radio, ensuring effective long-distance communication.