An Armatix employee holds a “smart gun” by the company at the Armatix headquarters in Munich May 14, 2014. The gun is implanted with an electronic chip that allows it to be fired only if the shooter is wearing a watch that communicates with it through a radio signal. If the gun is moved more than 10 inches (25 cm) from the watch, it will not fire. A Maryland gun shop owner has dropped his plan to be the first in the United States to sell the so-called “smart gun” after a backlash that included death threats. (Photo by Michael Dalder/Reuters)

A farmer seen harvesting his crops while Mount Sinabung spewing out volcanic ash on July 4, 2017 in North Sumatera, Indonesia. The increased volume of lava dome that reaches one million eight hundred cubic meters, said volcanologist, through radio communications, do not dampen the activities of the people around sinabung, such as farming, harvesting their crops, picking up objects that are still left behind, or just take a picture while walking around near mount Sinabung. (Photo by Sabirin Manurung/Pacific Press/Barcroft Images)

The Haʻikū Stairs, also known as the Stairway to Heaven or Haʻikū Ladder, is a steep hiking trail on the island of Oʻahu. The trail began as a wooden ladder spiked to the cliff on the south side of the Haʻikū Valley. It was installed in 1942 to enable antenna cables to be strung from one side of the cliffs above Haʻikū Valley to the other. A building to provide a continuous communication link between Wahiawā and Haʻikū Valley Naval Radio Station was constructed at the peak of Puʻukeahiakahoe, elevation about 2,800 feet (850 m). The antennae transmitted very low frequency radio signals from a 200,000-watt Alexanderson alternator in the center of Haʻikū valley. The signals could reach US Navy submarines as far away as Tokyo Bay while the submarines were submerged.

Emily Whiteford, 18, of Maryland, stretches before her audition for the Radio City Rockettes at Radio City Music Hall, Wednesday, April 3, 2024 in New York. (Photo by Brittainy Newman/AP Photo)

Artem, a 40-year-old Ukrainian commander, shouts a warning before his artillery team fires toward Russian positions near Pokrovsk in early October 2024. (Photo by Serhiy Nuzhnenko/Radio Free Europe/Radio Liberty)

A dancer applies make up before an audition for the Radio City Rockettes at Radio City Music Hall, Tuesday, April 22, 2025, in New York. (Photo by Julia Demaree Nikhinson/AP Photo)

Belarussian policemen detain a woman in central Minsk on August 11, 2020. Thousands of opposition supporters who also protested the results met with a tough police crackdown in Minsk and several other Belarusian cities for two straight nights. (Photo by Uladz Hrydzin/Radio Free Europe/Radio Liberty)

Radio City Music Hall Rockettes perform after days of rehearsal and routine polished to perfection at the Radio City Music Hall in New York City on July 26, 1949. (Photo by Ivan Dmitri/Getty Images)