By the early 1960's the development of Soviet missiles made the CONELRAD system obsolete.      

Facts about CONELRAD
The following fact sheet contains interesting facts and information on CONELRAD.

The Cold War reflected the icy relationship between the USSR and USA that started at the end of WW2. Developments in technology made it possible for Soviet war planes, loaded with nuclear weapons, to attack the American mainland.

The U.S. military advised the president that signals from domestic AM radio stations would help any approaching Soviet war planes to locate the position of major American towns and cities.

President Harry Truman signed Civil Defense Act of 1951 into law and authorized a new Federal Civil Defense Program

President Truman established CONELRAD in 1951 as the first national alerting system.  With the introduction of the system AM radio stations were required to broadcast only on 640 or 1240 kHz during an emergency alert to the public to ensure that enemy missiles could not use transmissions from broadcast stations as a guide for their targets.

CONELRAD stands for CONtrol of ELectronic RADiation and was an emergency radio broadcasting system that was introduced in 1951 by the United States government in 1951, for use in the event of a Soviet nuclear attack on the nation. At the same time there was the need to alert and keep people informed. 

The emergency radio broadcasting system was in addition to the existing siren warning systems.

Selected CONELRAD stations would broadcast warnings and information on either 604kHz or 1240kHz to inform the public about emergency measures.

In the event of a Soviet attack on the United States, all commercial radio stations would shut down, in order to prevent Soviet bombers from using radio commercial radio stations as navigation beacons.

All radios sold in the US after 1953 were required to have the CONELRAD frequencies 640/1240 kHz marked on the dials to make finding the frequencies easy.

Makeshift fallout shelters were designated in existing buildings with sturdy below-ground-level basements. Fallout shelters for high-ranking government officials and crucial military facilities were developed such as Project Greek Island and Cheyenne Mountain nuclear bunker.

The National Emergency Alarm Repeater (NEAR) program was developed in 1956 during the Cold War to supplement the existing siren warning systems and radio broadcasts in the event of a nuclear attack.

By the early 1960's the development of Soviet Intercontinental ballistic missiles (ICBMs) made the CONELRAD system obsolete. ICBMs were remote controlled and armed with nuclear warheads and had no need for AM radio signals.

In 1963 President Kennedy established the Emergency Broadcast System that allowed stations to broadcast emergency information whilst remaining on their assigned frequencies.