During World War II, ham radio as a hobby was heavily impacted due to wartime restrictions and the strategic importance of radio communications. Here’s a concise overview of what happened:

• Suspension of Amateur Radio: In most countries involved in the war, including the United States, amateur radio operations were banned or severely restricted. In the U.S., the Federal Communications Commission (FCC) ordered all amateur radio operators to cease operations by December 8, 1941, the day after the Pearl Harbor attack. This was due to concerns that enemy forces could exploit amateur radio signals for intelligence or sabotage.
• Equipment Confiscation and Repurposing: Ham radio operators were required to turn off their transmitters, and in some cases, equipment was confiscated or repurposed for military use. Many hams dismantled their stations to comply with regulations, though some kept low-profile receivers for listening.
• Hams in Military Service: Many amateur radio operators, with their technical skills and experience, were recruited or volunteered for military roles. They served as radio operators, technicians, and engineers, contributing to critical wartime communications. Organizations like the U.S. Army’s Signal Corps benefited significantly from their expertise.
• War Emergency Radio Service (WERS): In the U.S., the FCC created the War Emergency Radio Service in 1942, allowing some licensed hams to operate on specific frequencies for civil defense purposes, such as disaster response and air raid communications. This was a limited exception to the general ban, tightly controlled to avoid interference with military operations.
• Clandestine and Resistance Use: In occupied territories, some hams operated covertly to support resistance movements, relaying messages to Allied forces. These operations were highly risky, as detection by enemy forces often led to severe consequences.
• Post-War Revival: After the war ended in 1945, amateur radio gradually resumed. In the U.S., the FCC began lifting restrictions in late 1945, and by 1946, ham radio was largely restored. The hobby saw a surge in popularity as returning veterans, many trained in radio technology during the war, joined the ranks of operators.

The war temporarily suppressed ham radio as a hobby but also highlighted its value, as operators’ skills proved vital to the war effort. The post-war period marked a renaissance for the hobby, fueled by technological advances and renewed enthusiasm.