Despite many obstacles and threats from commercial and military radio, the efforts of a small number of determined 160-meter operators enabled the band allocation to survive.
The International Radio Conference of Atlantic City reduced the allocation to 1.8–2 MHz under the provision that amateurs must not interfere with LORAN operation.
[3] As the high frequency (HF) bands were developed in mid-1920s – along with their smaller, more feasible antennas – 160 meters fell into a period of relative disuse.
Amateurs were relegated to secondary, non-interfering status, with severe regional power limitations and restricted day/night operations on just a few narrow segments of the band.
Many older hams recall, with no great fondness, the ear-shattering buzz-saw racket of high power LORAN stations that began in 1942 until LORAN-A was phased out in North America on 31 December 1980, and most of the world by 1985.
Power restrictions above 1.9 MHz were removed in March 1984, and 160 meters was then no longer regarded as the "abandoned" band, as it had been for more than half a century.
160 meters is populated by many dedicated experimenters[citation needed], as it is a proving ground for ingenuity in antenna design and operating technique.
Effective operation on 160 meters can be more challenging than most other amateur bands, because of the overwhelmingly large sizes required for efficient antennas.